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We’ve reported on a technology called pulsed plasma rockets (PPRs) here at UT a few times. Several research groups have worked on variations of them. They are so popular partly because of their extremely high specific impulse and thrust levels, and they seemingly solve the trade-off between those two all-important variables in space exploration propulsion systems. Essentially, they are an extremely efficient propulsion methodology that, if scaled up, would allow payloads to reach other planets in weeks rather than months or years. However, some inherent dangers still need to be worked out, and overcoming some of those dangers was the purpose of a NASA Institute for Advanced Concepts (NIAC) project back in 2020. 

Originally granted to Howe Industries, a design shop that has received several NIAC grants (including two in 2020 itself), the purpose of this project was to model the design of a fully functional PPR in modeling software to see if the necessary materials and power systems are available for a rocket that can provide 100 kN of thrust and over 5,000 seconds of specific impulse. 

In essence, a PPR takes a fuel pellet made out of some form of fissionable material (in this case, uranium), and zaps it into a plasma, then emits the plasma out the back for a forceful thrust. Rockets with this design can carry much less fuel than standard chemical rockets, but their design must be significantly larger due to the heating constraints put on the system by creating the plasma in the first place.

SciShow discusses a scaled down version of the PPR proposed in the paper.
Credit – SciShow Space

Those heating constraints were one of the Phase I NIAC study’s main focal points in 2020. In particular, this study focused on analyzing the barrel the fuel pellet is released into to see if it could withstand the extreme temperatures created by handling a plasmatized uranium pellet.

To do this modeling, the team at Howe Industries used a modeling software called MCNP6 to check where particles went in the system and thereby calculate how much heat would be collected on other parts of the system where it wasn’t desired. MCNP6 uses a Monte Carlo simulation methodology, which calculates where neutrons will be created from the fission reaction that makes the plasma and where those neutrons will impact the rest of the spacecraft.

Those plasmas would have to be created about once every second, according to the calculations done by Howe Industries, and each pulse must reach an energy level of around 1 keV – much smaller than industrial-level nuclear fission reactors but a relatively high number for a spacecraft propulsion system. That energy is turned into heat, and while some of the heat is effectively used to eject the plasmatized uranium out as a thrust propellant, the rest is absorbed by other parts of the system. 

Troy Howe, one of the paper’s authors, discusses his research into the PPR.
Credit – Interstellar Research Group YouTube Channel

The barrel was a part of that system that is particularly important in these thermal calculations. The modeled barrel was made out of low-enriched uranium but of a different type than the projectile, allowing the energy to heat the projectile and not the barrel itself. However, a small part of the barrel would be made of highly enriched uranium, allowing for rapid plasma propagation in an otherwise relatively stable system.

That’s not to say that none of the heat generated by the fission reaction would end up in the barrel. Still, by the author’s calculations as part of their final report, an active cooling system should be enough to lower the temperature to a point where at least the barrel itself wouldn’t melt. Other parts of the system, such as the nozzle and a rotating drum that helps handle the fuel pellet, will be modeled in future work.

Additional future work would include building benchtop prototypes of these systems to test them out, though the prospect of working with highly enriched uranium as part of this process seems daunting. However, NIAC hasn’t yet funded a Phase II study of the PPR system, so for now, it is resigned to a nicely modeled project and another step forward in an idea that has plenty of history. Maybe someday, it will find its time to shine.

Learn More:
Howe et al. – Pulsed plasma rocket- developing a dynamic fission process for high specific impulse and high thrust propulsion
UT – Magnetic Fusion Plasma Engines Could Carry us Across the Solar System and Into Interstellar Space
UT – Plasma Thruster Could Dramatically Cut Down Flight Times to the Outer Solar System
UT – Plasma Rocket Could Help Pick Up Space Trash

Lead Image:
Model of the PPR design proposed in the paper.
Credit – Howe et al.

The post Thermal Modeling of a Pulsed Plasma Rocket Shows It Should Be Possible To Create One appeared first on Universe Today.

The Search for Extraterrestrial Intelligence has been ongoing for decades at this point. Despite that, we have yet to find any rock-hard evidence of a signal from an alien civilization. When asked about this, experts point out just how little of the overall signal space we’ve analyzed. A signal could be coming from anywhere in the sky, at any frequency, and might not be continuous. Constraining the “search space” could help us find a signal faster, but what could we use to constrain it? It’s hard to think like an alien intelligence, let alone to mimic them.

One of the most famous examples of the reverse of search is the Arecibo message, wherein humanity tried to announce, “We are here,” using scientific and mathematical standards like numbers and the atomic number of some elements (hydrogen and carbon, for example). Even so, it was still sent as a binary signal using a type of frequency modulation at a single point in time back in 1975. The likelihood that any civilization in the Messier 13 globular cluster, its intended target, will be able to both receive and interpret it is negligible. But it would help if they had a key to interpret it. But how can we convey a key to unlock the message without the key itself being interpretable only with the same key?

Naoki Seto of Kyoto University’s Department of Physics has spent a lot of time thinking about that question, and he came to a similar conclusion about the usefulness of scientific constants. In the past, he produced papers that suggested the time of a future binary star merger or a past supernova explosion to help narrow down a patch of sky to look at. However, with a new paper released on March 21st, he suggested a new idea – the orbital period of an exceptionally bright star around the Milky Way’s supermassive black hole.

Fraser discusses the most hyped finding of SETI so far – the WOW! signal.

The supermassive black hole at the center of our galaxy, known as Sgr A*, would be well known to any alien civilization advanced enough to send communication signals to announce their presence. It also, conveniently, has several super-bright stars that orbit it on regular periods. Dr. Seto selected one of those stars, known simply as S2.

S2 is a B-type star, is skewed toward the blue end of the stellar spectrum, and weighs in at about 15 times the mass of our own Sun. But most importantly, it is very, very bright and orbits Sgr A* with an orbital period of almost exactly 16 years. 

Those features are important because of their prominence but also because of the ease of calculations for something called the Schelling point. A Schelling point is derived from game theory – specifically, how two people can communicate about how to communicate without actually communicating. For example, someone wants to meet up with their partner but doesn’t want to tell them when or where they want to meet up. The other person is also interested in meeting up but equally interested in not communicating when or where. 

Fraser askes – are we ready to find aliens?

A Schelling point is thinking through reasonable touch points culturally to try to determine a place to meet without expressly saying it. In one example, knowing that we’re both Americans, if we were to pick one distinct time of year to meet up, and knowing that the other person is thinking the same thing, they might settle on something well known, such as midnight on New Year’s Eve. As for a place to meet, why not New York, the country’s largest city, and maybe Grand Central Station, the most common meeting place in that great city? That would be a Schelling point for two Americans, and the same inductive reasoning can be applied to communications with alien life forms.

S2 and its orbital period are something we would have in common with any alien life that develops in this galaxy – they would be able to see it from wherever they are. Dr. Seto thinks that using detailed characteristics of this one particular star, astronomers could start to search specific patches of sky for signals that use its orbital period as a basis for communication.

This is admittedly an arbitrary selection of a touch point for the Schelling point, but the general idea holds. The most likely way we can narrow down the absurd number of search parameters plaguing the search for extraterrestrial intelligence is to try to think like an alien and come up with some shared common experience that we can use as a basis to try to communicate without prior communication. It’s a tricky problem, and one that has lasted for decades, but, as with all things in science, the more people that get to thinking about them, the more likely they are to be solved.

Learn More:
Naoki Seto – A Proposal for Enhancing Technosignature Search toward the Galactic Center
UT – What is the Arecibo Message?
UT – What are the Best Ways to Search for Technosignatures?
UT – The 2nd Annual Penn State SETI Symposium and the Search for Technosignatures!

Lead Image:
Image of the galactic center. For the interferometric GRAVITY observations the star IRS 16C was used as a reference star, the actual target was the star S2. The position of the centre, which harbours the (invisible) black hole known as Sgr A*,with 4 million solar masses, is marked by the orange cross.
Credit – ESO / MPE / Gillessen et al.

The post Civilizations Could Time Their Communications Based on the Movement of a Single Star appeared first on Universe Today.

Rosalind Franklin, the ESA’s Mars rover, is scheduled to launch no sooner than 2028. Its destination is Oxia Planum, a wide clay-bearing plain to the east of Chryse Planitia. Oxia Planum contains terrains that date back to Mars’ Noachian Period, when there may have been abundant surface water, a key factor in the rover’s mission.

Rosalind Franklin’s primary mission mirrors that of NASA’s Perseverance rover: to search for fossil evidence of life. To do that, both rovers are equipped with a suite of powerful instruments. They both have sampling drills, but Franklin’s drill wins the tale of the tape. It can penetrate to a depth of two meters, compared to Perseverance’s which can only drill a few inches deep.

In order for the Franklin to be successful, it needs to land in a place where its drilling capability can be put to good use. That’s why the ESA chose Oxia Planum. Not only is it flat, which makes for a safer landing, but it contains hydrated minerals. In fact, it’s one of the largest exposed sections of clay-bearing minerals on Mars, and that’s where the fossilized evidence of life it seeks may be found.

A team of European scientists has created the most detailed geological map of Oxia Planum ever. It took four years to complete and leans heavily on data from orbiters. The detailed map shows 15 units with characteristic geological features that can help decide how the rover explores the area. The map will also help the rover interpret its surroundings and collect evidence of primitive life.

“This map is exciting because it is a guide that shows us where to find the answers.”

Peter Fawdon, co-lead author, Open University

Oxia Planum preserves a record of the forces that shaped the region and that shaped Mars. It’s a transitional region between Chryse Planitia, which contains lower elevation plains from the Amazonian/Hesperian, and Arabia Terra, the heavily cratered Noachian-aged region.

The sediments at Oxia Planum are nearly four billion years old. This will be the oldest site ever visited by a rover.

The new map has its roots in the COVID lockdowns. During that time, the Rosalind Franklin science team trained 80 volunteers to help them map Oxia Planum. The ExoMars Trace Gas Orbiter and NASA’s Mars Reconnaissance Orbiter supplied the data.

The result is a map that shows Oxia Planum’s geology in high detail. It shows types of bedrock and features like ridges and craters. It also shows crater ejecta and windborne dust. The map will not only help the rover navigate through difficult terrain; it’ll inform the choices of where to drill for samples.

This isn’t the first geological map of the Martian surface. But as this comparison shows, the new map (left) is much more detailed than previous ones (right.) The map on the right is a global geological map that labels the entire landing region as lNh, or late Noachian highlands. Image Credit: L: Fawdon et al. 2024. R: Tanaka et al. 2014.

“The map represents our current understanding of bedrock units and their relationships prior to Rosalind Franklin’s exploration of this location,” the map creators write in the paper presenting the map.

“The objectives of this map are (i) to identify where the most astrobiologically relevant rocks are likely to be found, (ii) to show where hypotheses about their geological context (within Oxia Planum and in the wider geological history of Mars) can be tested, (iii) to inform both the long-term (hundreds of metres to ~1 km) and the short-term (tens of metres) activity planning for rover exploration, and (iv) to allow the samples analyzed by the rover to be interpreted within their regional geological context,” the authors explain.

You can download the map and explore it here.

This is the new geological map of Oxia Planum, along with explanatory text. Image Credit: Fawdon et al. 2024.

“The wider region was extensively modified during the late Noachian and Hesperian periods, as shown by evidence of fluvial and paleo-lake activity, possible shoreline formation, volcanism, and aqueous alteration,” the authors write. The Hesperian is when Mars lost its water and transitioned from a warm, wet environment to a dry, cold environment. Understanding how that happened is a primary goal in Mars science.

The map contains a location and context section that orients viewers. The image on the left shows Rosalind Franklin’s landing site, and the image on the right shows the geological context. Image Credit: Fawdon et al. 2024.

The map shows mound materials, different types of bedrock, features like Mensas and crater materials of different ages.

This zoom-in of the map shows Sicilla Mensa, a flat-topped feature with cliff-like edges. oDm stands for overlying dark material. The image also shows craters and the extent of their ejecta, shown in yellow. It’s labelled rCm for recent crater material. Image Credit: Fawdon et al. 2024.

This is the highest-resolution map of the region ever made. With a scale of 1:25,000, each centimetre on the map equals 250 meters on Mars. Since Rosalind Franklin will travel an average of 25 to 50 meters each day, a day’s journey is one or two millimetres on the map.

The making of the map has already provided some benefits to the Rosalind Franklin mission. “The mapping exercise has provided the wider <ExoMars> rover team with a sound knowledge of the landing site and has also helped us to develop new geological hypotheses for the region,” the authors write.

Oxia planum is rich in clays, also called hydrated minerals. Because clays are formed in water-rich environments, it makes these sites excellent locations to study for clues as to whether life once began on Mars. Image Credit: ESA/Mars Express (OMEGA and HRSC) and NASA/Mars Reconnaissance Orbiter (CRISM). LICENCE: ESA Standard Licence

The map is more than just a driving guide. It’s essentially a summary of our hypotheses about Mars. When the rover begins its mission, its initial exploration and drilling will test some of these existing hypotheses for Martian geology and history. Those results will inform the rover team, leading to better decisions about where to drill and explore. That will “… improve the chances of the mission meeting its search for life goals,” the authors explain.

“This map is exciting because it is a guide that shows us where to find the answers. It serves as a visual hypothesis of what we currently know about the different rocks in the landing site. The instruments on Rosalind Franklin will allow us to test our knowledge on the spot when the time comes,” explained Peter Fawdon, one of the lead authors from the Open University.

The post The ESA’s Mars Rover Gets a New Map appeared first on Universe Today.

Catching a supernova in action is tricky business. There is no way to predict them, and they don’t occur very often. Within the Milky Way they only occur about once a century, and the last one was observed in 1604.

Of course, supernovae occur in other galaxies too, but you still have to get lucky to catch them as they explode.

But that’s what happened last year, according to a new paper released in Nature this week. Japanese amateur astronomer Koichi Itagaki, observing a nearby galaxy named Messier 101 (colloquially known as the Pinwheel Galaxy), recognized that something special was happening. He had just observed a new supernova. It was dubbed SN 2023ixf.

The initial phase of a supernova is measured in hours, so astronomers had to act fast. Within five hours, Itagaki had reported the sighting to an international astronomical reporting database called the Transient Name Server. Less than an hour after that, professional astronomers were already rushing to turn their telescopes to look at the new explosion.

The discovery took place on May 19, a Friday night, and it was a scramble to get everything in place across multiple time zones.

“It’s very rare, as a scientist, that you have to act so swiftly,” says Avishay Gal-Yam of the Weizmann Institute. “Most scientific projects don’t happen in the middle of the night, but the opportunity arose, and we had no choice but to respond accordingly.”

Messier 101 (the Pinwheel Galaxy), 21 million lightyears away, where supernova SN 2023ixf was discovered. ESA/NASA.

Gal-Yam’s PhD student and lead author of the paper, Erez Zimmerman, was part of the team who stayed up all night collecting data, and sharing information with the Hubble Space Telescope operators in time to make high-quality observations. Speed was of the essence.

“That’s what makes this particular supernova different,” says Zimmerman. “We were able – for the very first time – to closely follow a supernova while its light was emerging from the circumstellar material in which the exploding star was embedded.”

The team had already applied for time on Hubble, intending to observe existing supernovae remnants in UV light. They got lucky in being able to observe a brand-new one instead. And even luckier that Hubble had just recently observed the same area, meaning that they not only captured the supernova in action, but also captured the star and its conditions in the days immediately before the explosion. These before-and-after observations are incredibly valuable in understanding the final days of a star’s life.

“Stars behave very erratically in their senior years,” says Gal-Yam. “They become unstable and we usually cannot be sure which complex processes occur within them because we always start the forensic process after the fact, when much of the data has already been lost.”

Data from SN 2023ixf was also collected in X-ray from NASA’s Swift spacecraft, and spectra were obtained from the ground-based Keck Observatory in Hawai’i. Together, all these observations helped piece together the evolution of the explosion as it changed over time.

The remnants of Kepler’s supernova, which exploded within our galaxy in 1604. Composite image using data from Hubble, Chandra, and Spitzer space telescopes. NASA/ESA/JHU/R.Sankrit & W.Blair.

Another PhD student on the team, Ido Irani, says that the explosion probably formed a black hole, replacing the aged red giant that once sat in its place.

“Calculations of the circumstellar material emitted in the explosion, as well as this material’s density and mass before and after the supernova, create a discrepancy, which makes it very likely that the missing mass ended up in a black hole that was formed in the aftermath of the explosion – something that’s usually very hard to determine,” he says.

Follow-up observations are expected to provide even more details about the event, and help astronomers understand more precisely how supernovae occur and interact with their environment.

Learn More:

“A Hundred Million Suns.” Keck Observatory.

The post Astronomers Catch a Supernova Explode Almost in Realtime appeared first on Universe Today.

It’s a well known fact that black holes absorb anything that falls into them. Often before material ‘vanishes’ inside it forms into an accretion disk around them. Like the progenitor stars, the black holes have powerful magnetic fields and these can generate jets that blast away from the black hole. A similar process occurs in neutron stars that are orbiting other stars and recent observations holes have shown that some material in the jets travel at speeds 35-40% the speed of light. 

The European Space Agency launched the International Gamma Ray Astrophysics Laboratory (Integral) in October 2002. Its purpose to observe gamma ray events across the universe with energies up to 8 MeV (meagaelectron volts). Not only can it image gamma ray events, it can also provide spectroscopic analysis. Of all the gamma ray instruments in space, Integral is the most sensitive. It was using Integral that astronomers detected the high velocity jets. 

Artist’s illustration of Integral. Image credit: ESA

One of the chief methods used to identify the velocity of jets is to track matter moving along their length. This might sound easy but the distances to them are so extreme that observing their movement is difficult. A team of astronomers led by Thomas Russell from the National Institute for Astrophysics in Italy conjured up a cunning idea that neutron stars might help! 

Neutron stars are the result of the collapse of a massive star – effectively they are a whacking great neutron often around the size of Earth – and when a neutron star orbits another star, it can strip material off the companion. Most of the material accretes on the neutron star surface and wen it reaches a critical mass, a nuclear explosion occurs in an event known as a type-I x-ray burst. Some material however escapes this event by being ejected out of jets along the star’s rotational axis. 

Russell and his team concluded that the matter would be accelerated by the energy from the neutron star surface and it may be possible to measure the disturbance. The short lived impulse of extra material shot along the beam may make it easier to track. To date, there are 125 neutron stars that behave like this. If sufficient neutron stars with jets can be observed hen it may help us to understand the primary launching mechanism and whether magnetic fields from the star or material are key.

Two neutron stars (4U 1728-34 and 4U 1636-536) have been shown to exhibit x-ray burst events but only ’34 could be observed in radio wavelengths. x-ray events were observed on ‘536 but they only emitted radio waves. Supporting observations were needed from radio telescopes around the world. The bursts usually occur every few hours but it is difficult to predict. The Australian Telescope Compact Array chocked up 30 hours of observing in April 2021 and captured 14 x-ray bursts. The team were surprised to see that the nuclear explosion did not destroy the location where the jet launched but instead, saw strong input. The jets are well established phenomenon capable of withstanding such events. 

The new technique has shown that neutron star jets can be observed in this way so further observations are required to further explore the fascinating phenomena. 

Source : Integral spots giant explosions feeding neutron star jets?

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On February 15th, Intuitive Machines (IM) launched its first Nova-C class spacecraft from Kennedy Space Center in Florida atop a SpaceX Falcon 9 rocket. On February 22nd, the spacecraft – codenamed Odysseus (or “Odie”) – became the first American-built vehicle to soft-land on the lunar surface since the Apollo 17 mission in 1972. While the landing was a bit bumpy (Odysseus fell on its side), the IM-1 mission successfully demonstrated technologies and systems that will assist NASA in establishing a “sustained program of lunar exploration and development.”

After seven days of operation on the lunar surface, Intuitive Machines announced on February 29th that the mission had ended with the onset of lunar night. While the lander was not intended to remain operational during the lunar night, flight controllers at Houston set Odysseus into a configuration that would “call home” if it made it through the two weeks of darkness. As of March 23rd, the company announced that their flight controllers’ predictions were correct and that Odie would not be making any more calls home.

The company started listening for a wake-up signal from Odysseus on March 20th, when they projected that there was enough sunlight in the lander’s vicinity. At the time, it was thought that this could potentially charge Odysseus‘ power system, allowing it to activate its radio and reestablish contact with Houston. However, three days later, at 10:30 AM Central Standard Time (08:30 AM PST; 11:30 AM EST), flight controllers determined that the lander was not charging up after it completed its mission.

Image from the IM-1 Odysseus lander after it soft landed on the lunar surface. Credit: Intuitive Machines

This consisted of the Nova-C spacecraft making its inaugural soft landing on the Moon, the first time an American spacecraft has done so in over 50 years. The IM-1 mission was also the first time a spacecraft used methalox – the combination of liquid methane and liquid oxygen (LOX) – to navigate between the Earth and the Moon. While the IM-1 was not expected (or intended) to survive the lunar night, the data acquired by this mission could prove useful as the company continues to improve the lunar landing systems to deliver payloads to the Moon.

One of the company’s main objectives is to develop heat and power sources that can “keep systems from freezing during the lunar night.” This technology will greatly extend the life of lunar surface missions and facilitate the buildup of infrastructure on the Moon’s surface. A second Nova-C lander with the IM-2 mission will launch aboard a Falcon 9 no earlier than December 2024. This mission will land a drill and the Polar Resources Ice Mining Experiment-1 (PRIME-1) mass spectrometer near the south pole of the Moon.

This NASA payload will demonstrate the feasibility of In-Situ Resource Utilization (ISRU) and measure the volatile content of subsurface samples. ISRU and the presence of water are vital to the creation of a lunar base and the ability to send crews to the lunar surface well into the foreseeable future. A third mission (IM-3) is scheduled for early 2025, which will carry four NASA payloads to the Reiner Gamma region of the Moon, a rover, a data relay satellite, and secondary payloads to be determined. All three launches were contracted as part of NASA’s Commercial Lunar Payload Services (CLPS) program.

In addition, the IM-1 mission controllers and company managed to have a final farewell with the Odysseus mission before nightfall and the depletion of its battery power. On February 22nd, the lander transmitted a final image (shown below), which mission controllers in Houston received by February 29th. The image, Intuitive Machines said in a statement, “showcases the lunar vista with the crescent Earth in the backdrop, a subtle reminder of humanity’s presence in the universe. Goodnight, Odie. We hope to hear from you again.”

The last image sent by the IM-1 Odysseus mission on Feb. 22nd, 2024. Credit: Intuitive Machines

Further Reading: Intuitive Machines

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We can’t understand what we can’t clearly see. That fact plagues scientists who study how planets form. Planet formation happens inside a thick, obscuring disk of gas and dust. But when it comes to seeing through that dust to where nascent planets begin to take shape, astronomers have a powerful new tool: the James Webb Space Telescope.

In the past few years, we’ve been getting tantalizing looks at the protoplanetary disks around young stars. ALMA, the Atacama Large Millimetre/submillimetre Array, is responsible for that. It’s imaged many of these disks around young stars, including the telltale gaps where planets are likely forming.

ALMA’s high-resolution images of nearby protoplanetary disks are the results of the Disk Substructures at High Angular Resolution Project (DSHARP). Credit: ALMA (ESO/NAOJ/NRAO), S. Andrews et al.; NRAO/AUI/NSF, S. Dagnello

Imaging the disks is now becoming a regular occurrence, but astronomers have only spotted two forming planets.

But now researchers have brought the JWST to bear on the problem. Three new studies in The Astronomical Journal present the results of that effort. They are:

• JWST/NIRCam Imaging of Young Stellar Objects. I. Constraints on Planets Exterior to the Spiral Disk Around MWC 758
• JWST/NIRCam Imaging of Young Stellar Objects. II. Deep Constraints on Giant Planets and a Planet Candidate Outside of the Spiral Disk Around SAO 206462
• JWST/NIRCam Imaging of Young Stellar Objects. III. Detailed Imaging of the Nebular Environment around the HL Tau Disk

The research combines new JWST observations with previous observations by the Hubble and ALMA. The astronomers behind each of the studies used the JWST to uncover new, early clues about the planet formation process, including how the process shapes the disk they’re born from. If they can identify features unique to planet formation, they can then look for these features around other disks.

HL Tau, SAO 206462 and MWC 758 are all protoplanetary disks that have been observed by other telescopes. The JWST’s powerful infrared capabilities should provide new insights into these disks and their planets. That’s because as planets gather more material to them, they release infrared radiation.

“When material falls onto the planet, it shocks at the surface and gives off an emission line at specific wavelengths,” said astronomer Gabriel Cugno, who was involved with all three papers. “We use a set of narrow-band filters to try to detect this accretion. This has been done before from the ground at optical wavelengths, but this is the first time it’s been done in the infrared with JWST.”

MWC 758 is a young star that hosts a spiral protoplanetary disk.

This JWST/NIRCam image of MWC 758 shows the star’s unusual spiral disk. Wagner et al. 2024.

Using mathematical simulations, the researchers showed that a giant planet called MWS 758c outside the spirals can produce the spirals. They also showed that the symmetry of the arms can constrain the planet’s mass. In this case, they can determine a lower range for the planet’s mass: between about 4 to 8 Jupiter masses. But they didn’t find it. There may also be an even more massive companion further out, according to the simulations, but none was detected.

SAO 206462 is another young star surrounded by a disk. It also has clearly defined spiral arms, signifying the presence of a massive planet. The astronomers studying this star and disk did find a planet, but not the one they expected.

This is a JWST image of the star SAO 296462 and its spiral disk. Image Credit: Cugno et al. 2024.

“Several simulations suggest that the planet should be within the disk, massive, large, hot, and bright. But we didn’t find it. This means that either the planet is much colder than we think, or it may be obscured by some material that prevents us from seeing it,” said lead author Gabriele Cugno, also a co-author on the other paper papers. “What we have found is a different planet candidate, but we cannot tell with 100% certainty whether it’s a planet or a faint background star or galaxy contaminating our image. Future observations will help us understand exactly what we are looking at.”

Massive gas giants are expected to be responsible for the spiral shapes. But even the JWST struggles to find them. “The problem is, whatever we’re trying to detect is hundreds of thousands, if not millions of times fainter than the star,” Cugno said. “That’s like trying to detect a little light bulb next to a lighthouse.”

HL Tau is the third star and disk that the JWST examined and the youngest, at less than 100,000 years old. HL Tau is well-known in astronomy for the telltale gaps and rings in its disk, as well as some other features. For example, astronomers found water vapour in its disk right in the location where a suspected planet is forming.

In this image of HL Tau, observations from the Atacama Large Millimeter/submillimeter Array (ALMA) show water vapour in shades of blue in the same location where astronomers thought a planet may be forming. Image Credit: ALMA (ESO/NAOJ/NRAO)/S. Facchini et al.

The JWST found the known stellar envelope, outflow cavity, and other features. But, unfortunately, no planet.

This image from the paper shows an ALMA image of HL Tau and a JWST image of HL Tau. The JWST is able to see details that the ALMA image doesn’t show, including a feature called the hook-shaped clump. Image Credit: Mullin et al. 2024

“HL Tau is the youngest system in our survey and still surrounded by a dense inflow of dust and gas falling onto the disk,” said Mullin, a co-author of all three studies. “We were amazed by the level of detail with which we could see this surrounding material with JWST, but unfortunately, it obscures any signals from potential planets.”

One of the difficulties with HL Tau is its youth. The younger a star is, the more gas and dust is in the disk. It eventually gets taken up by planets, and the rest is dissipated by disk wind. But HL Tau is so young that the disk is very thick.

“While there is a ton of evidence for ongoing planet formation, HL Tau is too young with too much intervening dust to see the planets directly,” said Jarron Leisenring, the principal investigator of the observing campaign searching for forming planets and astronomer at the University of Arizona Steward Observatory. “We have already begun looking at other young systems with known planets to help form a more complete picture.”

But astronomy is full of surprises, especially when working with a powerful tool like the JWST. Astronomers often set out to find one thing and find something else they didn’t expect. That’s what happened with HL Tau.

This image of HL Tau from 2016 shows an inner gap and an outer gap where planets may be forming. Unfortunately, the JWST wasn’t able to detect them. But it did find other features. Image Credit: Yen et al. 2016.

In this case, the JWST detected HL Tau’s stellar envelope, where in-falling material gathers around the still coalescing young star. This material eventually becomes part of the star, disk, and planets.

While the astronomers behind all three papers hoped to find planets, that proved difficult. But the JWST’s sensitivity still helped them make progress.

“The lack of planets detected in all three systems tells us that the planets causing the gaps and spiral arms either are too close to their host stars or too faint to be seen with JWST,” said Wagner, a co-author of all three studies. “If the latter is true, it tells us that they’re of relatively low mass, low temperature, enshrouded in dust, or some combination of the three—as is likely the case in MWC 758.”

Planet formation could be the key to understanding how some planets end up with water and how other chemical elements are distributed in a solar system. Astronomers think that massive gas giants like Jupiter end up regulating the movement and flow of elements. But not all stars host planets so massive.

“Only about 15 percent of stars like the sun have planets like Jupiter. It’s really important to understand how they form and evolve and to refine our theories,” said U-M Michael Meyer, University of Michigan astronomer and coauthor of all three studies. “Some astronomers think that these gas giant planets regulate the delivery of water to rocky planets forming in the inner parts of the disks.”

Image of Jupiter taken by NASA’s Juno spacecraft. Massive gas giants like Jupiter might govern the movement of water in a young solar system, affecting which planets get it. That’s just one of the reasons why astronomers want to find them around young stars. (Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill)

In every disk that astronomers can get a good look at, they find gaps, rings, and sometimes spirals and other structures that can be explained by the formation of giant planets. But they also can’t rule out other explanations. And this is where the issue stands, for now.

“Basically, in every disk we have observed with high enough resolution and sensitivity, we have seen large structures like gaps, rings and, in the case of SAO 206462, spirals,” Cugno said. “Most if not all of these structures can be explained by forming planets interacting with the disk material, but other explanations that do not involve the presence of giant planets exist.”

Finding these massive planets forming around young stars is the next step. Even though the JWST didn’t find them, it still made progress on the issue. That’s how science works. Because if astronomers can eventually see some of these planets, they can then untangle the relationships between all the other features the JWST has observed with the planets themselves.

“If we manage to finally see these planets, we can connect some of the structures with forming companions and relate formation processes to the properties of other systems at much later stages,” Cugno said. “We can finally connect the dots and understand how planets and planetary systems evolve as a whole.”

Upcoming telescopes can make even more progress. The ESO’s Extremely Large Telescope will probe the earliest stages of planetary formation and will also detect water and organic chemicals in protoplanetary disks. Its first light is scheduled for 2028.

The Giant Magellan Telescope will also study the formation of planetary systems with its Near-Infrared Spectrograph. The GMT will see its first light in the 2030s.

The post Webb Joins the Hunt for Protoplanets appeared first on Universe Today.

Historical astronomical records from China and Japan recorded a supernova explosion in the year 1181. It was in the constellation Cassiopeia and it shone as bright as the star Vega for 185 days. Modern astronomers took their cue from their long-gone counterparts and have been searching for its remnant.

But it took them time to find it because they were looking for the wrong thing.

When a massive star runs out of fuel, it collapses in on itself and then explodes. It leaves behind a dense core where the protons and electrons are crushed into neutrons. It’s called a neutron star, and they’re the smallest and densest stellar objects in the Universe other than black holes.

It took a concerted effort from astronomers over the years to understand SN 1181’s remnant. At first, they couldn’t even find it.

For a time, researchers thought that the pulsar 3C 58 was the remnant. The ancient Chinese and Japanese records were not accurate enough to pinpoint SN 1181’s exact location, and the pulsar was the only known supernova remnant in the area. However, as astronomers studied 3C 58, they determined that it was much too old to be the remnant.

This X-ray image of pulsar 3C58 is from NASA’s Chandra X-ray Observatory. At 3500 years old, it’s too old to be the remnant of SN 1181. Image Credit: By NASA – http://apod.nasa.gov/apod/ap041223.htmlhttp://chandra.harvard.edu/photo/2004/3c58/, Public Domain, https://commons.wikimedia.org/w/index.php?curid=4074985

In 2013, an American amateur astronomer discovered a nebula, now named Pa 30, near the region where the Japanese and Chinese saw it. It has an extremely blue central star, and now the name Pa 30 refers to both the star and the nebula.

The cyan region in this image is where modern astronomers think SN 1181’s remnant should be, according to ancient Japanese and Chinese documents. Astronomers were guided by the ancient names and locations of constellations, like Wangliang and Ziwei. (Modern constellations are shown in grey.) The pulsar 3C58 is outside the region, while the white dwarf Pa 30 is inside it. Image Credit: By Bradley E. Schaefer – https://arxiv.org/abs/2301.04807, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=140937093

Eventually, in 2018, French amateur astronomers working with an 8-inch telescope spotted a very hot blue star in the remnant’s center. It had a very odd spectrum, unlike stars in the centers of other remnants. Then, in 2019, astronomers published a paper showing that the nebula had a fierce stellar wind with a high velocity. This was strong evidence that what they were seeing was a supernova remnant.

But where was the neutron star? There was none, and in its place was a white dwarf. That means that astronomers were wrong about what type of supernova SN 1181 was.

SN 1181 wasn’t a core-collapse supernova, the type caused by a massive star that collapses in on itself and then explodes as it runs out of fuel. It was a Type Iax, a supernova created when two white dwarfs merge and explode. Those explosions typically leave no remnants, but in this case, it did. The Type Iax explosion was incomplete, and it’s responsible for the SN remnant’s unusual shape and the fact that the remnant isn’t a neutron star but a zombie star.

The leading image is a composite image of the Pa 30, the name given to the remnant and the star. The data for the image comes from multiple telescopes that capture different parts of the electromagnetic spectrum.

A composite image of the remnant of supernova 1181, called Pa 30. G. Ferrand and J. English (U. of Manitoba), NASA/Chandra/WISE, ESA/XMM, MDM/R.Fessen (Dartmouth College), Pan-STARRS

X-rays captured by the ESA’s XMM-Newton spacecraft are shown in blue, tracing the nebula’s full extent. NASA’s Chandra X-ray Observatory pinpointed the central source in the middle, the star named WD J005311. With a temperature greater than 220,000 Kelvin, it’s the hottest star known.

The remnant is almost invisible in optical light but is bright in infrared. NASA’s Wide-field Infrared Space Explorer (WISE) captured the infrared, shown in red and pink in the image. The nebula’s radial structure is interesting and has an unusual cause. The lines are heated sulphur glowing in visible light, captured by the ground-based Hiltner 2.4 m telescope at the MDM Observatory. The background stars were imaged with Pan-STARRS.

The ancient Japanese and Chinese who recorded the event had no real idea what they were seeing. They were more like court bureaucrats than astronomers, and they were steeped in astrology, not science. A member of the Japanese imperial court wrote that the supernova was “a sign of abnormality.” Another chronicler wrote that it was an “occasion for making auspicious offerings for a good harvest.”

But modern science shows us that it’s none of those things. Instead, it’s a wondrous object in the distant heavens, the result of forces and energies that the ancients had no idea existed. As a supernova, it forged heavy elements—especially the ones needed for life to appear—and spread them out into space. Its shock waves could’ve even triggered the birth of more stars as it slammed into the interstellar medium.

They couldn’t have known any of this, but from their perspective, they were right about one thing. As a Type Iax supernova that left behind a zombie star, SN 1181 was definitely a sign of abnormality.

The post This Supernova Lit Up the Sky in 1181. Here’s What it Looks Like Now appeared first on Universe Today.

We know how stars form. Clouds of interstellar gas and dust gravitationally collapse to form a burst of star formation we call a stellar nursery. Eventually, the cores of these protostars become dense enough to ignite their nuclear furnace and shine as true stars. But catching stars in that birth-moment act is difficult. Young stars are often hidden deep within their dense progenitor cloud, so we don’t see their light until they’ve already started shining. But new observations from the Hubble Space Telescope have given us our earliest glimpse of a shiny new star.

You can see this image above, which captures the dusty region of the FS Tau system. The bright star just to the right of center is FS Tau A, which is a young star just 2.8 million years old. An infant compared to our Sun’s 4.6 billion years. But the exciting discovery is a bit higher and further right, known as FS Tau B. That line of dust obscuring the protostar is its protoplanetary disk seen edge-on. The light coming from the obscured star isn’t produced by nuclear fusion, but rather the late stages of gravitational collapse.

You can also see that the protostar has begun to produce radiant jets, which are reflected against the dusty nebula as regions of blue light. Because of this reflected light, FS Tau B is classified as a Herbig-Haro (HH) object. HH objects are great for helping astronomers understand the early dynamics of these stars.

FS Tau B is likely in the early stages of becoming a T Tauri star. These are sun-like stars just on the edge of becoming true stars. They can be quite active, with starspots and large flares, but can take 100 million years for one to ignite their cores and settle into a true main-sequence star. As that happens, protoplanets will form within the dusty disk, ready to become full planets in time.

You can find more information about the FS Tau system, as well as high-resolution images and videos, on the ESA Hubble website.

The post Hubble Sees a Star About to Ignite appeared first on Universe Today.

Anyone can be an underachiever, even if you’re an astronomical singularity weighing over four billion times the mass of the Sun. At least the quasar H1821+643 doesn’t have parents to be disappointed in it. But its underachievement could shed light on how quasars, a potent type of black hole, can come to influence entire clusters of galaxies, as described in a new paper from researchers at the University of Nottingham and Harvard.

Using X-ray data from the Chandra observatory, the researchers looked closely at H1821+643 and decided it influenced its local environment much less than expected. Granted, a lot was expected of it – quasars are super powerful black holes that rapidly pull in new material rapidly and eject radiation as well as sometimes emitting powerful streams of particles. In particular, H1821+643 is a quasar located about 3.4 billion light-years away from Earth at the center of a cluster of galaxies. 

Both the quasar and its surrounding galaxy are shrouded in a field of hot gas that showed up as a fuzzy haze in Chandra’s X-ray dataset. That fuzzy haze, which would let astronomers understand what was happening to the gas in the galaxy at large, was massively overwhelmed by the brightness of the X-rays emitted from the quasar itself.

Fraser describes what quasars are.

To study the effects of the quasar on the location gas population, the researchers had to remove the effects of its own X-rays, leaving only the light emitted from the gas itself. They found that the gas is significantly less hot than might be expected given its proximity to such a forceful quasar, showing that the quasar itself isn’t outputting as much energy as might otherwise be expected.

Counterintuitively, the Chandra data shows that the density of gas around the quasar is higher. At the same time, the temperature is cooler than areas of the galaxy that are further away from the center. If the quasar were emitting the typical series of outbursts, they would have expected there to be not as much gas close to the quasar itself, as the outbursts would have blown it away and that what gas there was close in would be heated to extraordinarily high temperature by those same outbursts.

Without those outbursts, though, the local environment appears to be rife for star formation. The authors estimate that gas equivalent to about 3,000 times the mass of our Sun cools below the point where it emits X-rays every year. Some of that cooling gas is formed into about 120 solar masses worth of new stars yearly, while the black hole itself swallows up another 40 solar masses. What happens with the thousands of solar masses of gas left over after those two processes is anyone’s guess.

Here’s a fund, speculative video from Fraser about whether our own supermassive black hole could become a quasar.

However, the quasar itself isn’t cooling the gas surrounding it. At least not much. This process can happen when photons emitted from the black hole run into the electrons of the surrounding gas, resulting in an energy transfer that increases the energy of the photon but decreases the energy of the electron – hence causing the gas to cool down. While that process might be ongoing near H1821-643, the authors calculate that it would only explain a small percentage of the cooling of the gas they observed.

In short, much is still unknown about this seemingly unique quasar system. Studying it further can help scientists understand the influence these massive singularities can have on their immediate surroundings and physical properties more generally. At least, no matter what H1821-643’s physical properties might be, it won’t be getting chewed out by its parents.

Learn More:
NASA / CXC – NASA’s Chandra Identifies an Underachieving Black Hole
Russell et al. – A cooling flow around the low-redshift quasar H1821+643
UT – What Is A Quasar?
UT – This New Map of 1.3 Million Quasars Is A Powerful Tool

Lead Image:
Image of the H1821-643 quasar.
Credit: X-ray: NASA/CXC/Univ. of Nottingham/H. Russell et al.
Radio: NSF/NRAO/VLA
Image Processing: NASA/CXC/SAO/N. Wolk

The post This Black Hole is a Total Underachiever appeared first on Universe Today.

The Solar and Heliospheric Observatory (SOHO) was designed to examine the Sun, but as a side benefit, it has been the most successful comet hunter ever built. Since early in the mission, citizen scientists have been scanning through the telescope’s data, searching for icy objects passing close to the Sun. An astronomy student in Czechia has identified 200 comets in SOHO data since he started in 2009 at the age of 13. He recently spotted the observatory’s 5,000th comet.

“Prior to the launch of the SOHO mission and the Sungrazer Project, there were only a couple dozen sungrazing comets on record – that’s all we knew existed,” said Karl Battams, who is the principal investigator for the Sungrazer Project, the citizen science project that was launched after so many comets started showing up in the data. “The fact that we’ve finally reached this milestone – 5000 comets – is just unbelievable to me.”

SOHO moves around the Sun on the sunward side of Earth, where it enjoys a clear, uninterrupted view of the Sun, by slowly orbiting around Lagrange point L1.  That means it has been observing the Sun 24 hours a day, 365 days a year without interruptions since shortly after it launched in 1995. With this view, SOHO can easily spot the kind of comet that’s known as a sungrazer – so named because of their close approach to the Sun. Many of these comets don’t survive their close pass to the Sun.

Many congratulations to Hanjie Tan (@HonkitTan) for making that 5,000th discovery! Hanjie has been discovering comets with the Sungrazer Project since he was 13yrs old, and is now pursuing for his PhD studying asteroids! pic.twitter.com/wa51ZlVnjm

— Karl Battams (@SungrazerComets) March 27, 2024

Hanjie Tan is the student who discovered the 5,000th comet. Inspired by his many years of searching for comets, Tan is now an astronomy PhD student in Prague, Czechia, studying comets and asteroids. The small comet that he spotted is part of the ‘Marsden group’ of comets, named after the British astronomer Brian Marsden, who first recognized the group based on SOHO observations. Marsden group comets are thought to be pieces shed by the much bigger Comet 96P/Machholz, which SOHO observes as it passes close to the Sun every 5.3 years.

“The Marsden group comets represent only about 1.5% of all SOHO comet discoveries,” said Tan in an ESA press release, “so finding this one as the 5000th SOHO comet felt incredibly fortunate. It’s really exciting to be the first to see comets get bright near the Sun after they’ve been travelling through space for thousands of years.”

Artist’s impression of the SOHO spacecraft studying the Sun. Credit: NASA/ESA.

The SOHO mission has now been operational for almost 30 years. It’s almost been lost twice and is now flying without the use of its gyroscopes, which help it point precisely. Engineers have figured out a way to work around the issue. It’s longevity has not only provided an incredible treasure trove of data about the Sun, but it also has allowed the spacecraft to become the most prolific discoverer of comets in astronomical history.

Related: 22 years of the Sun from SOHO

Launched in 1995, SOHO studies the Sun from its interior to its outer atmosphere, providing unique views and investigating the cause of the solar wind. During the last three decades, SOHO has become the most prolific discoverer of comets in astronomical history.

“A huge congratulations to EVERYONE who has ever contributed to Sungrazer,” Battams said on Twitter. “Hanjie may have found #5000, but it took 24-years of combined volunteer ‘amateur’ scientist efforts to find the other 4,999. This was a team effort, and I’m so thankful to all who have helped!”

The post Someone Just Found SOHO's 5,000th Comet appeared first on Universe Today.

Measuring the distance to far away objects in space can be tricky. We don’t even know the precise distance to even our closest neighbors in the Universe – the Small and Large Magellanic Clouds. But, we’re starting to get to the tools to measure it. One type of tool is a Cepheid Variable – a type of star that varies its luminosity in a well-defined pattern. However, we don’t know much about their physical properties, making utilizing them as distance markers harder. Finding their physical properties would be easier if there were any Cepheid binaries that we could study, but astronomers have only found one pair so far. Until a recent paper from researchers from Europe, the US, and Chile shows measurements of 9 additional binary Cepheid systems – enough that we can start understanding the statistics of these useful distance markers.

Like traditional stars, binary Cepheid systems result when two stars orbit around each other. In this case, both of those stars must be Cepheids – meaning they are massive compared to our Sun and much brighter. In addition, their luminosity must vary in a repeatable pattern so that we can track it consistently.

All of those features can vary a lot if two stars change in luminosity but at different rates and phases around each other. It’s difficult to parse out which star is waxing, which is waning, and which direction they are moving in, both compared to us and each other. Long periods of observation are required to fix some of those variables, and that is precisely what the new paper describes.

The researchers looked at nine sets of Cepheids that were believed to be binary systems but hadn’t yet been confirmed due to the difficulty of separating the two stars from each other. They pulled data from the Optical Gravitational Lensing Experiment (OGLE) database, a variable star observation project run by the University of Warsaw for over 30 years. In so doing, they could confirm, for the first time, that each of these suspected binaries contained two separate stars.

Those nine binary systems were located in the Small and Large Magellanic Cloud and the Milky Way. One located in the Milky Way is by far the closest, at only 11 kiloparsecs (about 3000 light-years) away. The researchers also had good luck because of the length of orbital periods of the binaries they studied – most were over five years, and a shorter observational data set might not have caught them. 

Understanding how these systems exist and where they are is just the first step. Using them for more helpful science is the next. The most obvious way to do so is to increase our understanding of Cepheids. Despite being one of the most commonly used distance markers in the Universe, we know surprisingly little about how they form, what they’re made of, or their life cycle. Closely studying a binary system, where the stars interact, could help shed light (figuratively in this sense) on some of those properties.

Calibrated Period-luminosity Relationship for Cepheids
Credit – NASA

As the authors point out in their paper, this is part of a long-term ongoing project – they were also part of the team that confirmed the original Cepheid binary system back in 2014. OGLE continues to collect more data, as are other sky surveys, and there are likely more Cepheid binaries out there. Every new discovery will help improve our statistical understanding of these critical distance markers – we just need to take the time to find them first.

Learn More:
Pilecki et al. – Cepheids with giant companions II. – Spectroscopic confirmation of nine new double-lined binary systems composed of two Cepheids
UT – What are Cepheid Variables?
UT – Polaris is the Closest, Brightest Cepheid Variable. Very Recently, Something Changed.
UT – Astronomers Rule Out One Explanation for the Hubble Tension

Lead Image:
RS Puppis , one of the brightest known Cepheid variable stars in the Milky Way galaxy
Credit – NASA, ESA, and the Hubble Heritage Team

The post Astronomers Only Knew of a Single Binary Cepheid System. Now They Just Found Nine More appeared first on Universe Today.

On September 26th, 2022, NASA’s Double Asteroid Redirection Test (DART) collided with the asteroid Dimorphos, a moonlet that orbits the larger asteroid Didymos. The purpose of this test was to evaluate a potential strategy for planetary defense. The demonstration showed that a kinetic impactor could alter the orbit of an asteroid that could potentially impact Earth someday – aka. Potentially Hazardous Asteroid (PHA). According to a new NASA-led study, the DART mission’s impact not only altered the orbit of the asteroid but also its shape!

The study was led by Shantanu P. Naidu, a navigation engineer with NASA’s Jet Propulsion Laboratory (JPL) at Caltech. He was joined by researchers from the Lowell Observatory, Northern Arizona University (NAU), the University of Colorado Boulder (UCB), the Astronomical Institute of the Academy of Sciences of the Czech Republic, and Johns Hopkins University (JHU). Their paper, “Orbital and Physical Characterization of Asteroid Dimorphos Following the DART Impact,” appeared on March 19th in the Planetary Science Journal.

The Didymos double asteroid system consists of an 851-meter-wide (2792 ft) primary orbited by the comparatively small Dimorphos. The latter was selected as the target for DART because any changes in its orbit caused by the impact would be comparatively easy to measure using ground-based telescopes. Before DART impacted with the moonlet, it was an oblate spheroid measuring 170 meters (560 feet) in diameter with virtually no craters. Before impact, the moonlet orbited Didymos with a period of 11 hours and 55 minutes.

Artist’s impression of the DART mission impacting the moonlet Dimorphos. Credit: ESA

Before the encounter, NASA indicated that a 73-second change in Dimorphos’ orbital period was the minimum requirement for success. Early data showed DART surpassed this minimum benchmark by more than 25 times. As Naidu said in a NASA press release, the impact also altered the moonlet’s shape:

“When DART made impact, things got very interesting. Dimorphos’ orbit is no longer circular: Its orbital period is now 33 minutes and 15 seconds shorter. And the entire shape of the asteroid has changed, from a relatively symmetrical object to a ‘triaxial ellipsoid’ – something more like an oblong watermelon.”

Naidu and his team combined three data sources with their computer models to determine what happened to the asteroid after impact. The first was the images DART took of Dimorphos right before impact, which were sent back to Earth via NASA’s Deep Space Network (DSN). These images allowed the team to gauge the dimensions of Didymos and Dimorphos and measure the distance between them. The second source was the Goldstone Solar System Radar (GSSR), part of the DNS network located in California responsible for investigating Solar System objects.

The GSSR was one of several ground-based instruments that precisely measured the position and velocity of Dimorphos relative to Didymos after impact – which indicated how the mission greatly exceeded expectations. The third source was provided by ground-based telescopes worldwide that measured changes in the amount of life reflected (aka. light curves) of both asteroids. Much like how astronomers monitor stars for periodic dips (which could indicate a transiting planet), dips in Didymos’ luminosity are attributable to Dimorphos passing in front of it.

Artist’s impression of the ESA’s Hera mission rendezvousing with Dimorphos. Credit: NASA

By comparing these light curves from before and after impact, the team learned how DART altered Dimorphos’ motion. Based on these data sources and their models, the team calculated how its orbital period evolved and found that it was now slightly eccentric. Said Steve Chesley, a senior research scientist at JPL and a co-author on the study:

“We used the timing of this precise series of light-curve dips to deduce the shape of the orbit, and because our models were so sensitive, we could also figure out the shape of the asteroid. Before impact, the times of the events occurred regularly, showing a circular orbit. After impact, there were very slight timing differences, showing something was askew. We never expected to get this kind of accuracy.”

According to their results, DART’s impact reduced the average distance between the two asteroids to roughly 1,152 meters (3,780 feet) – closer by about 37 meters (120 feet). It also shortened Dimorphos’ orbital period to 11 hours, 22 minutes, and 3 seconds – a change of 33 minutes and 15 seconds. These results are consistent with other independent studies based on the same data. They will be further tested by the ESA’s Hera mission, scheduled to launch in October 2024, when it makes a flyby of the double-asteroid and conducts a detailed survey.

Further Reading: NASA

The post DART Changed the Shape of Asteroid Dimorphos, not Just its Orbit appeared first on Universe Today.

Universe Today has had some fantastic discussions with researchers on the importance of studying impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, and planetary geophysics, and how these diverse scientific fields can help researchers and the public better understand the search for life beyond Earth. Here, we will investigate the unique field of cosmochemistry and how it provides researchers with the knowledge pertaining to both our solar system and beyond, including the benefits and challenges, finding life beyond Earth, and suggestive paths for upcoming students who wish to pursue studying cosmochemistry. But what is cosmochemistry and why is it so important to study it?

“Cosmochemistry is the study of space stuff, the actual materials that make up planets, stars, satellites, comets, and asteroids,” Dr. Ryan Ogliore, who is an associate professor of physics at Washington University in St. Louis, tells Universe Today. “This stuff can take all the forms of matter: solid, liquid, gas, and plasma. Cosmochemistry is different from astronomy which is primarily concerned with the study of light that interacts with this stuff. There are two main benefits of studying actual astromaterials: 1) the materials record the conditions at the time and place where they formed, allowing us to look into the deep past; and 2) laboratory measurements of materials are extraordinarily precise and sensitive, and continue to improve as technology improves.”

In a nutshell, the field of cosmochemistry, also known as chemical cosmology, perfectly sums up Carl Sagan’s famous quote, “The cosmos is within us. We are made of star-stuff. We are a way for the cosmos to know itself.” To understand cosmochemistry is to understand how the Earth got here, how we got here, and possibly how life got wherever we’re (hopefully) going to find it, someday.

Like all scientific fields, cosmochemistry incorporates a myriad of methods and strategies with the goal of answering some of the universe’s most difficult questions, specifically pertaining to how the countless stellar and planetary objects throughout the universe came to be. These methods and strategies primarily include laboratory analyses of meteorites and other physical samples brought back from space, including from the Moon, asteroids, and comets. But what are some of the benefits and challenges of studying cosmochemistry?

“One of the primary benefits of cosmochemistry is the ability to reproduce measurements,” Dr. Ogliore tells Universe Today. “I can measure something in my lab, and somebody else can measure either the same object, or a very similar object, in another lab to confirm my measurements. Only after repeated measurements, by different labs and different techniques, will a given claim be universally accepted by the community. This is difficult to do in astronomy, and also difficult using remote-sensing measurements on spacecraft studying other bodies in the Solar System.”

Apart from the crewed Apollo missions to the Moon, all other samples from space have been returned via robotic spacecraft. While this might seem like an easy process from an outside perspective, collecting samples from space and returning them to Earth is a very daunting and time-consuming series of countless tests, procedures, precise calculations, and hundreds to thousands of scientists and engineers ensuring every little detail is covered to ensure complete mission success, often to only collect a few ounces of material. This massive effort is tasked with not only ensuring successful sample collection, but also ensuring successful storage of the samples to avoid contamination during their journey home, and then retrieving the samples once they land in a capsule back on Earth, where they are properly unpacked, cataloged, and stored for laboratory analysis.

To demonstrate the difficulty in conducting a sample return mission, only four nations have successfully used robotic explorers to collect samples from another planetary body and returned them to Earth: the former Soviet Union, United States, Japan, and China. The former Soviet Union successfully returned lunar samples to Earth throughout the 1970s; the United States has returned samples from a comet, asteroid, and even solar particles; Japan has successfully returned samples from two asteroids; and most recently, China succeeded in returning 61.1 ounces from the Moon, which is the current record for robotic sample return missions. But even with the difficulty of conducting a successful sample return mission, what can cosmochemistry teach us about finding life beyond Earth?

“Cosmochemistry can tell us about the delivery of the ingredients necessary for life to planets or moons via asteroids or comets,” Dr. Ogliore tells Universe Today. “Since we have both asteroid and comet material in the lab, we can tell if primitive pre-biotic organic compounds may have been delivered by these bodies. Of course, this doesn’t mean life on Earth (or elsewhere) started this way, only that it is one pathway. Detection of life on another world would be one of the biggest discoveries in the history of science. So of course we’d want to be absolutely sure! This requires repeated measurements by different labs using different techniques, which requires a sample on Earth. I think the only way we’d know for sure if there was life on Europa, Enceladus, or Mars is if we bring a sample back to Earth from these places.”

As it turns out, NASA is actively working on the Mars Sample Return (MSR) mission, for which Dr. Ogliore is a member of the MSR Measurement Definition Team. The goal of MSR will be to travel to the Red Planet to collect and return samples of Martian regolith to Earth for the first time in history. The first step of this mission is currently being accomplished by NASA’s Perseverance rover in Jezero Crater, as it is slowly collecting samples and dropping them in tubes across the Martian surface for future retrieval by MSR.

For Europa, while there have been several discussions regarding a sample return mission, including a 2002 study discussing a sample return mission from Europa’s ocean and a 2015 study discussing a potential plume sample return mission, no definitive sample return missions from Europa are currently in the works, possibly due to the enormous distance. Despite this, and while not a life-finding mission, Dr. Ogliore has been tasked to lead a robotic mission to Jupiter’s volcanic moon, Io, to explore its plethora of volcanoes. For Enceladus, the Life Investigation for Enceladus (LIFE) mission has had a number of mission proposals submitted to return samples from Enceladus’ plumes, though it has yet to be accepted. But what is the most exciting aspect about cosmochemistry that Dr. Ogliore has studied during his career?

Image from NASA’s Cassini spacecraft of the water vapor plumes emanating from the south pole of Saturn’s moon Enceladus. (Credit: NASA/JPL/Space Science Institute)

“In my opinion the most important single measurement in the history of cosmochemistry was the measurements of the oxygen isotopic composition of the Sun,” Dr. Ogliore tells Universe Today. “To do this, we needed to return samples of the solar wind to Earth, which we did with NASA’s Genesis mission. However, the sample return capsule crashed on Earth. But did that stop the cosmochemists?! Hell no! Kevin McKeegan and colleagues at UCLA had built a specialized, enormous, complicated instrument to study these samples. Despite the crash, McKeegan and colleagues analyzed oxygen in the solar wind and found that it was 6% lighter than oxygen found on Earth, and it matched the composition of the oldest known objects in the Solar System: millimeter-sized calcium-aluminum inclusions (CAIs) found in meteorites.”

Dr. Ogliore continues by telling Universe Today about how this result was predicted by Bob Clayton at the University of Chicago, along with crediting his own postdoc, Lionel Vacher, for conducting a research project that built off the Genesis results, noting, “This was a really fun project because it was technically very challenging, and the results put the Solar System in its astrophysical context.”

Like the myriad of scientific disciplines that Universe Today has examined during this series, cosmochemistry is successful due to its multidisciplinary nature that contributes to the goal of answering some of the universe’s most difficult questions. Dr. Ogliore emphasizes that analysis of laboratory samples involves a multitude of scientific backgrounds to understand what the researchers are observing within each sample and the processes responsible for creating them. Additionally, this also includes the aforementioned sample return missions and hundreds to thousands of scientists and engineers who partake in each mission. Therefore, what advice can Dr. Ogliore offer to upcoming students who wish to pursue cosmochemistry?

“Biology, chemistry, geology, physics, math, electronics — you need it all!” Dr. Ogliore tells Universe Today. “If you like learning new things constantly, then planetary science is for you. It is good to get a very broad education. This will serve you well in a number of careers, but it is especially true for planetary science and cosmochemistry. I get to work with people who study volcanoes, and mathematicians working on chaotic motion. How cool is that?!”

All things considered, cosmochemistry is both an enormously challenging and rewarding field of study to try and answer some of the most difficult and longstanding questions regarding the processes responsible for the existence of celestial bodies in the Solar System and beyond, including stars, planets, moons, meteorites, and comets, along with how life emerged on our small, blue world. As noted, cosmochemistry perfectly sums up Carl Sagan’s famous quote, “The cosmos is within us. We are made of star-stuff. We are a way for the cosmos to know itself.” It is through cosmochemistry and the analysis of meteorites and other returned samples that enable researchers to slowly inch our way to answering what makes life and where we can find it.

“Meteorites are the most spectacular record of nature known to mankind,” Dr. Ogliore tells Universe Today. “We have rocks from Mars, the Moon, volcanic worlds, asteroid Vesta, and dozens of other worlds. Iron meteorites are the cores of broken apart planets. These rocks record processes that occurred four and a half billion years ago and fall to Earth in a blazing fireball traveling at miles per second. You can follow various blogs that track fireballs, and even calculate areas where meteorites might have fallen. If you ever have the opportunity, go try to find one of these freshly fallen meteorites. The odds are long, but it is worth a try. I have not found a meteorite myself yet, but it is a life goal of mine.”

How will cosmochemistry help us better understand our place in the universe in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

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Since its launch in 2021, the James Webb Space Telescope (JWST) has made some amazing discoveries. Recent observations have found a number of key ingredients required for life in young proto-stars where planetary formation is imminent. Chemicals like methane, acetic acid and ethanol have been detected in interstellar ice. Previous telescopic observations have only hinted at their presence as a warm gas. Not only have they been detected but a team of scientists have synthesised some of them in a lab.

These molecules found in the solid stage phase in young protostars are an indicator that the processes leading to formation of life may be more common than first thought. The complex organic molecules (COMs) were first predicted decades ago before space telescopes observations inconclusively identified them. A team of astronomers using the Mid-InfraRed Instrument (MIRI) on the JWST as part of the James Webb Observations of Young ProtoStars programme have identified the COMs individually. 

MIRI, ( Mid InfraRed Instrument ), flight instrument for the James Webb Space Telescope, JWST, during ambient temperature alignment testing in RAL Space’s clean rooms at STFC’s Rutherford Appleton Laboratory, 8th November 2010.

One of the target objects observed as part of this study was IRAS 2A, a low mass protostar. The science team are particularly interested because the system has similar characteristics as our own star, the Sun. It gives us a great test bed to explore the processes of the Solar System and Earth’s development.

The presence in the solid phase and earlier detections in the gas phase suggests the process behind their existence is sublimation of ice. The process of sublimation is the transition straight from solid to gas without going through the liquid phase. The detection of COMs in ice suggests this is the origin of the COMs in gas. 

The scientific community are now looking at the liklihood of transportation of the COMs to early planets as they form around the young stars. It is believed that their transportation as an ice are far more efficient to the protoplanetary disks than as a gas. It is quite likely that the icy COMs can be transported and inherited by comets and asteroids  as the planets form. These new icy objects that develop can then, through their impacts, carry the complex molecules to planets, seeding them with the ingredients for life.

A closeup of the inner region of the Orion Nebula as seen by JWST. There’s a protoplanetary disk there that is recycling an Earth’s ocean-full of water each month. Credit: NASA, ESA, CSA, PDRs4All ERS Team; Salomé Fuenmayor image

The team not only detected complex molecules, they also detected formic acid (the stuff that makes some insect bites sting), sulphur dioxide and formaldehyde. The sulphur dioxide was particularly useful since it allowed the team to calculate the deposits of oxidised sulphur as a function of emissions of the same. This is particularly of interest since it was pivotal in the development of metabolic reactions and processes in the young Earth. 

A team from the University of Hawaii’s Department of Chemistry led by Professor Ralf I. Kaiser managed to synthesise a complex molecule known as Glyceric Acid. Understanding its formation process helps us to understand how life evolved on Earth. The experiments used interstellar model ices and estimates of Galactic Cosmic Ray levels to form Glyceric Acid with a photo ionisation laser. This may have been similar to the role of lightning in the evolution of our own atmosphere.

Source : Cheers! Webb finds ethanol and other icy ingredients for worlds and Unraveling the origins of life: Scientists discover ‘cool’ sugar acid formation in space

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Solar sails rely upon pressure exerted by sunlight on large surfaces. Get the sail closer to the Sun and not surprisingly efficiency increases. A proposed new mission called Mercury Scout aims to take advantage of this to explore Mercury. The mission will map the Mercurian surface down to a resolution of 1 meter and, using the highly reflective sail surface to illuminate shadowed craters, could hunt for water deposits. 

Unlike conventional rocket engines that require fuel which itself adds weight and subsequently requires more fuel, solar sails are far more efficient. Light falling upon the sail can propel a prob across space. It’s a fascinating concept that goes back to the 1600’s when Johannes Kepler suggested the idea to Galileo Galilei. It wasn’t until the beginning of the 21st Century that the Planetary Society created the Cosmos 1 solar sail spacecraft. It launched in June 2005 but a failure meant it never reached orbit. The first successfully launched solar sail was Ikaros, launched by the Japanese Aerospace Exploration Agency it superbly demonstrated the feasibility of the technology. 

Artist’s illustration of IKAROS. Credit: JAXA

It has been known since 1905 that light is made up of tiny little particles known as photons. They don’t have any mass but while travelling through space, they do have momentum. When a tennis ball hits a racket, it bounces off the strings and some of the ball’s momentum is transferred to the racket. In a very similar way, photons of light hitting a solar sail transfer some of their momentum to the sail giving it a small push. More photons hitting the sail give another small push and as they slowly build up, the spacecraft slowly accelerates. 

Mercury Scout will take advantage of the solar sail idea as its main propulsion once it has reached Earth orbit. The main objectives for the mission are to map out the mineral distribution on the surface, high resolution imaging down to 1 meter resolution and identification of ice deposits in permanently shadowed craters. The solar sail was chosen because it offers significant technical and financial benefits lowering overall cost and reducing transit time to Mercury. 

To propel the Mercury Scout module, the sail will be around 2500 square meters and 2.5 microns thick. The material is aluminised CP1 which is similar to that used in the heat shield of the James Webb Space Telescope. The sails four separate quadrants unfurl along carbon fibre supports and will get to Mercury in an expected 3.8 years. On arrival it will transfer into a polar orbit and then spend another 176 days mapping the entire surface. 

To enable the entire planet to be mapped the the orbit will have to be maintained by adjusting the angle of the sail. In the same way the captain of a sailing ship can sail against, or sometimes into wind by adjusting sail angle and position so the solar sail can be used to generate thrust in the required direction. 

Data from the Mercury Atmosphere and Surface Composition Spectrometer, or MASCS, instrument is overlain on the mosaic from the Mercury Dual Imaging System, or MDIS. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Unlike other more traditional rocket engines whose life is usually limited to fuel availability, the solar sail is limited by degradation in sail material. Its life expectancy is around 10 years. Additional coatings are being explored to see if the life of the sail can be extended further. 

Source : MERCURY SCOUT: A SOLAR SAIL MISSION TO THE INNERMOST PLANET

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From its vantage point at the Sun-Earth L2 point, the ESA’s Euclid spacecraft is measuring the redshift of galaxies with its sensitive instruments. Its first science images showed us what we can expect from the spacecraft. But the ESA noticed a problem.

Over time, less light was reaching the spacecraft’s instruments.

Euclid launched on July 1st, 2023 and made its way to the Sun-Earth Lagrange 2 point, the same spot where the JWST resides. Euclid is basically a wide-angle telescope with a 600 MB camera. Using its suite of scientific instruments, it measures the redshift of galaxies in an effort to understand the accelerating expansion of the Universe. Its measurements support the mission’s main science goals: to understand dark matter and dark energy.

Euclid released its first images in November 2023. To describe them as dazzling was not an exaggeration. Those images whetted our appetite for more and built anticipation for the science results to come.

The first test images from the Euclid spacecraft. Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. CC BY-SA 3.0 IGO or ESA Standard Licence

But as time went on, a problem common to spacecraft cropped up. Water vapour from Earth had accumulated on the spacecraft during construction. Over time, the water was released from different parts of the spacecraft by the vacuum of space. The water attached to and froze to the first object it came into contact with. Some of it froze into a thin layer of water ice on VIS, the telescope’s visible wavelength camera. The layer was no thicker than a strand of DNA, but the sensitive instrument was nonetheless impaired.

Euclid personnel couldn’t see the ice. Instead, they observed a growing decrease in the amount of light reaching VIS. VIS is extremely sensitive and is designed to deliver the best low-light sensitivity ever achieved over a broad range of wavelengths. But that sensitivity to light also makes it very sensitive to even a small drop in starlight caused by the thin film of ice.

ESA personnel spent months trying to devise a method of removing the ice, and on March 19th, they started implementing their plan.

This image shows Euclid’s interior, VIS and NISP, and the path light will take as it reflects off of the spacecraft’s mirrors. Image Credit: ESA

Euclid has six different mirrors that collect light and deliver it to VIS and NISP, the Near-Infrared Spectrometer and Photometer. The team in charge of dealing with the ice problem devised a way to heat the spacecraft without compromising the instruments’ sensitivity. They planned to heat the mirrors one by one, and after the first mirror was warmed by 34 degrees F, the ice melted away.

“It was midnight at ESOC mission control when we de-iced the first two mirrors in the procedure. We were very careful with our timings, ensuring we had constant contact between the spacecraft and our ground station in Malargüe, Argentina, so we could be ready to react in real-time if there were any anomalies,” explained Micha Schmidt, Euclid Spacecraft Operations Manager.

“Thankfully, it all went as planned. When we saw the first analysis provided by the science experts, we knew that they would be very happy – the result was significantly better than expected,” Schmidt said.

“It was an enormous team effort over the last months to plan, execute and analyze the heating of selected mirrors onboard Euclid, resulting in the fantastic result we see now,” explained Ralf Kohley, Euclid Instrument Scientist and in charge of the anomaly review board.

This figure shows the results of the effort to warm up Euclid’s mirrors and remove the ice. At about the 90-minute mark, the temperature reached the point where ice sublimes into water vapour. After that point, the amount of light the spacecraft collected rose dramatically. Image Credit: ESA/Euclid/Euclid Consortium. ESA Standard Licence

Since the light collection improved on the first attempt, the success also showed mission personnel exactly where the ice was and where it’s likely to collect in the future if the problem crops up again.

“The mirrors and the amount of light coming in through VIS will continue being monitored, and the results from this first test will continue to be analyzed as we turn this experiment into a core part of flying and operating Euclid,” Kohley said.

With this problem behind it, Euclid can now get back to work. Its goal is to measure galaxies out to redshift 2. This corresponds to looking back in time by 10 billion years. The spacecraft will do it gradually, measuring the shapes of galaxies and their corresponding redshifts. The spacecraft will also measure how their light is distorted by dark matter. Eventually, the telescope will measure the amount of dark matter and compare its statistical properties to those of the galaxies. Critically, it will measure them over long periods of time, leading to an understanding of how both change over time and a better understanding of dark matter, dark energy, and the acceleration of the expansion of the Universe, the spacecraft’s main scientific goal.

But none of that work can continue if the telescope can’t see properly. Even the thin film of ice impaired Euclid’s observations enough that it was a serious obstacle to progress.

Now that the ice is gone, Euclid can get back to work. And if the problem reappears, the Euclid team is ready to deal with it.

“We expect ice to cloud the VIS instrument’s vision again in the future,” explained Reiko Nakajima, VIS instrument scientist. “But it will be simple to repeat this selective decontamination procedure every six to twelve months and with very little cost to science observations or the rest of the mission.”

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Fresh imagery from the Event Horizon Telescope traces the lines of powerful magnetic fields spiraling out from the edge of the supermassive black hole at the center of our Milky Way galaxy, and suggests that strong magnetism may be common to all supermassive black holes.

The newly released image showing the surroundings of the black hole known as Sagittarius A* — which is about 27,000 light-years from Earth — is the subject of two studies published today in The Astrophysical Journal Letters. This picture follows up on an initial picture issued in 2022. Both pictures rely on radio-wave observations from the Event Horizon Telescope’s network of observatories around the world.

Sagittarius A* wasn’t the first black hole whose shadow was imaged by the EHT. Back in 2019, astronomers showed off a similar picture of the supermassive black hole at the center of the galaxy M87, which is more than a thousand times bigger and farther away than the Milky Way’s black hole.

In 2021, the EHT team charted the magnetic field lines around M87’s black hole by taking a close look at the black hole in polarized light, which reflects the patterns of particles whirling around magnetic field lines. Researchers used the same technique to determine the magnetic signature of Sagittarius A*, or Sgr A* for short.

Getting the image wasn’t easy, largely due to the fact that Sgr A* was harder to pin down than M87. The EHT team had to combine multiple views to produce a composite image.

“Making a polarized image is like opening the book after you have only seen the cover,” EHT project scientist Geoffrey Bower, an astronomer at Academia Sinica in Taiwan, explained in today’s news release. “Because Sgr A* moves around while we try to take its picture, it was difficult to construct even the unpolarized image. … We were relieved that polarized imaging was even possible. Some models were far too scrambled and turbulent to construct a polarized image, but nature was not so cruel.”

The resulting picture met the research team’s expectations, and then some.

“What we’re seeing now is that there are strong, twisted and organized magnetic fields near the black hole at the center of the Milky Way galaxy,” said project co-leader Sara Issaoun, an astronomer at the Harvard-Smithsonian Center for Astrophysics. “Along with Sgr A* having a strikingly similar polarization structure to that seen in the much larger and more powerful M87* black hole, we’ve learned that strong and ordered magnetic fields are critical to how black holes interact with the gas and matter around them.”

The structure of the magnetic fields around Sgr A* suggests that the black hole is launching a jet of material into the surrounding environment. Previous research has shown that to be the case for M87’s black hole.

A computer simulation of the disk of plasma around M87’s supermassive black hole shows how magnetic fields help launch jets of matter at near the speed of light. Scientists say the Milky Way’s black hole appears to be doing something similar. (Credit: George Wong/ EHT)

“The fact that the magnetic field structure of M87* is so similar to that of Sgr A* is significant because it suggests that the physical processes that govern how a black hole feeds and launches a jet might be universal among supermassive black holes, despite differences in mass, size and surrounding environment,” said EHT deputy project scientist Mariafelicia De Laurentis, a professor at the University of Naples Federico II in Italy.

In the seven years since the EHT began gathering observations, the collaboration has been adding to its array of radio telescopes, which is resulting in the production of higher-quality imagery. The EHT team plans to observe Sgr A* again next month — and in the years ahead, the researchers aim to produce high-fidelity movies of Sgr A* that may reveal a hidden jet. They’ll also look for evidence of similar polarization features around other supermassive black holes.

More than 300 researchers are part of the EHT collaboration that produced the two studies published today in The Astrophysical Journal Letters:

• “First Sagittarius A* Event Horizon Telescope Results. VII. Polarization of the Ring”
• “First Sagittarius A* Event Horizon Telescope Results. VIII. Physical Interpretation of the Polarized Ring”

More explanatory videos from the Event Horizon Telescope:

• An Introduction to the EHT
• What Is Polarization?
• The Power of Polarized Imaging

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The Solar System’s icy ocean moons are primary targets in our search for life. Missions to Europa and Enceladus will explore these moons from orbit, improving our understanding of them and their potential to support life. Both worlds emit plumes of water from their internal oceans, and the spacecraft sent to both worlds will examine those plumes and even sample them.

New research suggests that evidence of life in the moons’ oceans could be present in just a single grain of ice, and our spacecraft can detect it.

It’s all because of improvements to scientific instruments, particularly the mass spectrometer. Mass spectrometers can identify unknown chemical compounds by their molecular weights and can also quantify known compounds. These instruments are now powerful enough to detect a tiny amount of cellular material.

“For the first time, we have shown that even a tiny fraction of cellular material could be identified by a mass spectrometer onboard a spacecraft,” said Fabian Klenner, a University of Washington postdoctoral researcher in Earth and space sciences. Klenner is also the lead author of a new paper in the journal Science Advances. “Our results give us more confidence that using upcoming instruments, we will be able to detect lifeforms similar to those on Earth, which we increasingly believe could be present on ocean-bearing moons.”

The new research is “How to identify cell material in a single ice grain emitted from Enceladus or Europa.“

Mass spectrometers have been around for decades but have improved rapidly in recent years. Researchers working on developing more powerful mass spectrometry have won two Nobel Prizes: one for Physics in 1989 and one for Chemistry in 2002. The 2002 prize is of particular interest in this research because it was awarded for the development of techniques that allowed mass spectrometers to detect biological macromolecules, including proteins.

Now, spacecraft and rovers often have mass spectrometers in their suite of instruments. NASA’s Curiosity rover has one, and so will the Europa Clipper, which will be sent on its way to Europa in October 2024. It’ll arrive there in 2030, so this research makes its anticipated arrival even more intriguing.

We know that Enceladus and Europa emit cryovolcanic plumes of material from their concealed oceans. The Cassini mission observed these eruptions coming from Enceladus’ south-polar region. Eventually, the spacecraft came within 50 km of the icy moon and passed directly through the plumes. Using its mass spectrometer, it detected carbon dioxide, water, various hydrocarbons, and organic chemicals.

A false-colour image of the plumes erupting from Enceladus. Image Credit: NASA/ESA

“Enceladus has got warmth, water and organic chemicals, some of the essential building blocks needed for life,” said Dennis Matson in 2008, a Cassini project scientist at NASA’s JPL at the time.

Europa also has cryovolcanic plumes. The Hubble Space Telescope spotted them in 2012, and then scientists working with data from the Galileo mission said that data supported the discovery.

This composite image shows suspected plumes of water vapour erupting at the 7 o’clock position off the limb of Jupiter’s moon Europa. The plumes, photographed by Hubble’s Imaging Spectrograph, were seen in silhouette as the moon passed in front of Jupiter. Hubble’s ultraviolet sensitivity allowed for the features, rising over 160 kilometres above Europa’s icy surface, to be discerned. The Hubble data were taken on January 26, 2014. The image of Europa, superimposed on the Hubble data, is assembled from data from the Galileo and Voyager missions. Image Credit: NASA/HST/STScI

When the Europa Clipper reaches its destination in 2030, it’ll employ an instrument called SUDA, the SUrface Dust Analyzer. SUDA will use mass spectrometry to detect chemicals in Europa’s plumes. This research suggests that SUDA should be able to detect cellular material on a single ice grain if it’s there.

This artist’s illustration shows what Europa might be like. Warm water containing organic material could make its way from the ocean, through cracks in the ice, out into space on ice grains via cryovolcanic plumes. Image Credit: NASA

This research is based on a common bacterium found in Alaskan waters. It’s called Sphingopyxis alaskensis, and the researchers chose it because it’s so small. It also lives in cold environments and can survive on few nutrients. It’s possible that its small size and other attributes make it an analogue for any life that may exist in Europa’s ocean.

In their experiments, the researchers simulated how mass spectrometry could detect organic material in a tiny ice grain. The results showed that along with detecting expected non-organic chemicals, mass spectrometry also detected amino acids from Sphingopyxis alaskensis.

“They are extremely small, so they are, in theory, capable of fitting into ice grains that are emitted from an ocean world like Enceladus or Europa,” Klenner said.

This figure from the research shows the cationic mass spectrum of the cell material equivalent to one S. alaskensis cell in a 15-?m-diameter H2O droplet. Although the mass spectrum is dominated by water, sodium-water, potassium-water, and ammonium-water clusters, amino acids, together with other metabolic intermediates from the S. alaskensis cell, can be identified. The spectrum is an average of 224 individual spectra. Image Credit: Klenner et al. 2024.

The search for life at Europa may come down to individual grains of ice. That’s partly because different molecules end up in different ice grains. If biological material is concentrated in ice grains, then it makes sense to detect individual ones rather than averaging results over a larger sample of ice.

But will there actually be biological material in ice grains? How would it get there?

On Earth, bacterial cells are encased in protective lipid membranes. That means that they sometimes form a surface layer on the ocean or other bodies of water. If the same is true of any life that may exist on Europa or Enceladus, then these bacteria can form a skin on the surface of the ocean. On these icy moons, gas bubbles that rise from the ocean and burst at the surface could incorporate cellular matter from the bacteria into the plumes.

The drawing on the left shows Enceladus and its ice-covered ocean, with cracks near the south pole that are believed to penetrate through the icy crust. The middle panel shows where life could thrive: at the top of the water, in a proposed thin layer (shown yellow) like on Earth’s oceans. The right panel shows that as gas bubbles rise and pop, bacterial cells could get lofted into space with droplets that then become the ice grains that were detected by Cassini. A mass spectrometer should be able to detect cellular matter on a single ice grain. Image Credit: European Space Agency

“We here describe a plausible scenario for how bacterial cells can, in theory, be incorporated into icy material that is formed from liquid water on Enceladus or Europa and then gets emitted into space,” Klenner said.

This is where mass spectrometry and SUDA come in. SUDA is much more powerful than earlier mass spectrometers, and has the capability to detect the fatty acids and lipids that may be launched into the plumes. While detecting actual DNA might seem like the holy grail, Klenner disagrees.

“For me, it is even more exciting to look for lipids, or for fatty acids, than to look for building blocks of DNA, and the reason is because fatty acids appear to be more stable,” Klenner said.

In their paper, the researchers state their results clearly. “Our experiments show that even if only 1% of a cell’s constituents are contained in a 15-micrometre ice grain (or one cell in a 70-micrometre-diameter grain), the bacterial signatures would be apparent in the spectral data,” they explain.

This is good news for the Europa Clipper and its SUDA instrument.

“With suitable instrumentation, such as the SUrface Dust Analyzer on NASA’s Europa Clipper space probe, it might be easier than we thought to find life, or traces of it, on icy moons,” said senior author Frank Postberg, a professor of planetary sciences at the Freie Universität Berlin. “If life is present there, of course, and cares to be enclosed in ice grains originating from an environment such as a subsurface water reservoir.”

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If all goes well, NASA’s Artemis III mission will bring humans back to the Moon as early as 2026, the first time since the Apollo 17 crew departed in 1972. It won’t be a vacation, though, as astronauts have an enormous amount of science to do, especially in lunar geology. A team from NASA recently presented their planetary science goals and objectives for Artemis III surface activities, which will guide the fieldwork the astronauts will carry out on the lunar surface.

The Artemis III Geology Team presented their priorities at the Lunar and Planetary Science Conference in March 2024. In addition, NASA also announced their choices for the first science instruments that astronauts will deploy on the surface of the Moon during Artemis III.

The landing site hasn’t been chosen yet, but it will be within 6 degrees of latitude from the South Pole. These instruments will collect valuable scientific data about the lunar environment, the lunar interior, and how to sustain a long-duration human presence on the Moon, which will help prepare NASA to send astronauts to Mars.

“Artemis marks a bold new era of exploration, where human presence amplifies scientific discovery. With these innovative instruments stationed on the Moon’s surface, we’re embarking on a transformative journey that will kick-start the ability to conduct human-machine teaming – an entirely new way of doing science,” said NASA Deputy Administrator Pam Melroy. “These three deployed instruments were chosen to begin scientific investigations that will address key Moon to Mars science objectives.”

Two of the three main Artemis science goals and the instruments deal with understanding the Moon itself. The Lunar Environment Monitoring Station (LEMS) is a compact, autonomous seismometer suite will help study planetary processes, while the Lunar Dielectric Analyzer (LDA) will aid in understanding the character and origin of lunar polar volatiles. The third main science objective will investigate how to mitigate the risks of human exploration, and to that end the Lunar Effects on Agricultural Flora (LEAF) instrument will investigate the lunar surface environment’s effects on space crops to see if the lunar regolith can be used to grow food.  

Artist’s concept of an Artemis astronaut deploying an instrument on the lunar surface. Credits: NASA

Falling under the planetary science goals with the two instruments, scientists have laid out four main objectives, which are designed to be “site agnostic,” so that they can be performed at any landing site, or be able to be modified to fit with any future chosen landing site.

• A. Understand the Early Evolution of the Moon as a Model for Rocky Planet Evolution

The main objective here is to evaluate the leading theory of the Moon’s early days, which is the Lunar Magma Ocean (LMO) theory. It is theorized that a layer of molten rock was present on the surface of the Moon from the time of the Moon’s formation (about 4.5 or 4.4 billion years ago) to tens or hundreds of millions of years after that time, which led to the formation of the crust, mantle, and core. While the LMO model is supported by many observations, it is not supported by all.

The scientists said gathering samples from the Moon’s polar region and comparing the ages and chemical and isotopic compositions of the new samples to those collected by the Apollo astronauts will help to evaluate the current LMO model and perhaps “find alternate or more complex LMO models.” Scientists would also like to determine the composition of the lower crust, and mantle materials if possible.

Artist’s impression of the impact that caused the formation of the Moon. Credit: NASA/GSFC

Another theory that scientists hope to put under scrutiny during the Artemis program is the giant impact hypothesis. This is the most widely accepted theory for the origin of the Earth–Moon system, which proposes the Moon formed during a collision between the Earth and another small planet, about the size of Mars. The debris from this impact collected in an orbit around Earth to form the Moon. However, similarities between the Earth and Moon don’t quite fit that model, the majority of the Moon’s material should originate from the impactor. “The Artemis III samples will allow new assessments of the formation process and age of the Moon,” the scientists wrote.

• B. Determine the Lunar Record of Inner Solar System Impact History.

Impacts played a big role in the early history of our Solar System, and scientists say they would like to determine the age of South Pole Aitken (SPA) Basin, the oldest known lunar impact basin. “This will provide key new information for determining when the record of bombardment starts and how complete that early record is,” the scientists wrote. They also hope to determine the sources of early impactors, which will provide a fundamental benchmark for understanding the ages of surfaces across the Solar System.

Scientists would also like to gather data to test the Lunar Cataclysm Hypothesis, a theory that says an intense period of bombardment occurred on the Moon about 3.9 billion years ago, where about 80% of the Moon was “resurfaced,” with the formation of approximately 1,700 craters 100 kilometers in size or larger.  This hypothesis is controversial, but determining if this period of bombardment did occur would help scientists determine if a similar cataclysmic bombardment may have affected life on Earth or been involved in life’s origins.

For the two above goals, the Lunar Environment Monitoring Station (LEMS) will carry out continuous, long-term monitoring of the seismic environment, namely ground motion from moonquakes, in the lunar south polar region. This instrument is expected to operate for at least three months and up to two years and may become a key station in a future global lunar geophysical network. NASA said the instrument will characterize the regional structure of the Moon’s crust and mantle, providing valuable information to analyze the current lunar formation and evolution models.

•  C & D: Determine the Variability of Regolith in the Circumpolar Environment as a Keystone for Understanding Surface Modification of Airless Bodies, and Reveal the Age, Origin, and Evolution of Solar System Volatiles

The Moon’s poles – and especially the permanently shadowed regions – have been compared to an attic in an old house, because it likely contains a record of history. On the Moon, the “attic-like” regions near the poles would still hold the exogenous material delivered to the inner Solar System. Since the terrestrial record of the early Earth is largely lost, finding it on the Moon would be extremely valuable.  

A map showing the permanently shadowed regions (blue) that cover about 3 percent of the moon’s south pole. Credit: NASA Goddard/LRO mission

“Little is known about cold-trapped volatile composition, abundance, age, and the general ability of the Moon to retain volatiles over time,” the scientists wrote. “….Assessing volatiles in cold traps of varying thermal environments and age will provide key new observations to understand their nature.”

And there’s also growing evidence for the presence of lunar polar volatiles like water, hydrogen, and methane, which would be extremely important for future long-term habitation on the Moon. Scientists also want to study how volatiles might be transported across the lunar surface, as such transport has yet to be measured on the Moon, and how it might occur – whether it driven by diurnal temperature changes, solar wind or and micrometeoroid delivery across the Moon.

The Lunar Dielectric Analyzer (LDA) will help in these studies as it will measure the regolith’s ability to propagate an electric field, which is a key parameter in the search for lunar volatiles, especially ice. It will gather essential information about the structure of the Moon’s subsurface, monitor dielectric changes caused by the changing angle of the Sun as the Moon rotates, and look for possible frost formation or ice deposits.

“These three scientific instruments will be our first opportunity since Apollo to leverage the unique capabilities of human explorers to conduct transformative lunar science,” said Joel Kearns, deputy associate administrator for exploration in NASA’s Science Mission Directorate in Washington. “These payloads mark our first steps toward implementing the recommendations for the high-priority science outlined in the Artemis III Science Definition Team report.”

With the Artemis program, NASA will land the first woman, first person of color, and its first international partner astronaut on the Moon, and with the goal of establishing long-term exploration for scientific discovery and preparation for human missions to Mars for the benefit of all.

For more details, you can read the Planetary Science Goals and Objectives for Artemis III Surface Activities document here, and the Artemis III Science Definition Team Report.

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