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Researchers have developed a three-dimensional mathematical model of prostate cancer. The model depicts various processes, including tumour growth, genetic evolution and tumour cell competition.

When it comes to telescopes, bigger really is better. A larger telescope brings with it the ability to see fainter objects and also to be able to see more detail. Typically we have relied upon larger and larger single aperture telescopes in our attempts to distinguish exoplanets around other stars. Space telescopes have also been employed but all that may be about to change. A new paper suggests that multiple telescopes working together as interferometers are what’s needed. 

When telescopes were invented they were single aperture instruments. A new technique emerged in the late 1800’s to combine optics from multiple instruments. This achieved higher resolution than would ordinarily be achieved by the instruments operating on their own. The concept involves analysis of the interference pattern when the incoming light from all the individual optical elements is combined. This is used very successfully in radio astronomy for example at the aptly named Very Large Array. It is not just radio waves that are used, infra-red and even visible light interferometers have been developed saving significant costs and producing results that would otherwise not be achievable from a single instrument.

Image of radio telescopes at the Karl G. Jansky Very Large Array, located in Socorro, New Mexico. (Credit: National Radio Astronomy Observatory)

One area of astronomical research is the study of exoplanets. Observing alien worlds orbiting distant stars presents a number of challenges but the two key difficulties are that they lie at great distances and orbit bright stars. The planets are usually small and faint making them almost (but not quite) impossible to study directly due to the brightness and proximity to their star. Some understanding of their nature can be gleaned from using the transit method of study. This involves studying starlight as it passes through any atmosphere present to reveal its composition. 

Direct imaging and study is a little more challenging and requires high resolution and sometimes a way of blocking light from the nearby star. To achieve direct observations requires angular resolution of a few milliarcseconds or even less (the full Moon covers 1,860,000 milliarcseconds!) This depends largely on the planets size and distance from Earth and from its host star. To give some idea of context, to resolve a planet like Earth orbiting the Sun from a distance of just 10 light years requires an angular resolution of 0.1 milliarcseconds. The James Webb Space Telescope has a resolution of 70 milliarcseconds so even that will struggle. 

This artist’s impression depicts the exomoon candidate Kepler-1625b-i, the planet it is orbiting and the star in the centre of the star system. Kepler-1625b-i is the first exomoon candidate and, if confirmed, the first moon to be found outside the Solar System. Like many exoplanets, Kepler-1625b-i was discovered using the transit method. Exomoons are difficult to find because they are smaller than their companion planets, so their transit signal is weak, and their position in the system changes with each transit because of their orbit. This requires extensive modelling and data analysis.

A paper recently authored by Amit Kumar Jha from the University of Arizona and a team of astronomers explores this very possibility. They look at using interferometry techniques to achieve the required resolutions, at using advanced imaging techniques like the Quantum Binary Spatial Mode Demultiplexing to analyse the point spread function (familiar to amateur astronomical imagers) and at using quantum based detectors.

The study draws upon radio interferometric techniques with promising results. They showed that a multi-aperture interferometry approach utilising quantum based detectors are more effective than single aperture instruments. They will provide a super-resolution imaging solution that has to date not been used in exoplanetary research. Not only will it hugely increase resolution, it’s also a very cost effective way to observe exoplanets and indeed other objects across the cosmos. 

Source : Multi-aperture telescopes at the quantum limit of super-resolution imaging : Detecting subRayleigh object near a star

The post Interferometry Will Be the Key to Resolving Exoplanets appeared first on Universe Today.

The Proba-3 mission consists of two spacecraft that will fly in close formation to study the sun, with the shadow of one creating an artificial solar eclipse from the perspective of the other

Pluto may have been downgraded from full-planet status, but that doesn’t mean it doesn’t hold a special place in scientist’s hearts. There are practical and sentimental reasons for that – Pluto has tantalizing mysteries to unlock that New Horizons, the most recent spacecraft to visit the system, only added to. To research those mysteries, a multidisciplinary team from dozens of universities and research institutes has proposed Persephone – a mission to the Pluto system that could last 50 years.

New Horizons rocketed past the Pluto system in 2015, which is now technically considered part of the Kuiper Belt. The mission collected data on the dwarf planet and its unique moon, Charon. Scientists have now had time to analyze the data from that mission, and it left them wanting more—in particular, data about some of the surface features that they observed.

Persephone has four main scientific questions it is designed to answer, according to a paper published back in 2021:

1) “How has the population of the Kuiper Belt evolved?”
2) “What are the particle and magnetic field environments of the Kuiper Belt?”
3) “How have the surfaces of both Pluto and Charon changed?”
4) “What are the internal structures of Pluto and Charon?”

Fraser discusses what we learned about Pluto from New Horizons

That last one might be the most intriguing, as the answer for Pluto’s internal structure might be that it has a subsurface ocean despite being so far away from the Sun. There is already some evidence for this, as Pluto appears to have an active surface, and an ice sheet called Sputnik Planitia could potentially be caused by a subsurface ocean. We don’t have enough data yet to prove it.

That is what Persephone is designed to provide. Unfortunately, with the unforgiving logic of orbital mechanics and current constraints on propulsion technology, any such mission would take multiple decades, even with a gravity assist from Jupiter. The mission design for Persephone has been operational for almost 31 years, including a 28-year cruise phase and a three-year orbit period around Pluto and Charon. It could then have an extended operational mission to visit other Kuiper belt objects to help constrain the variance in the different kinds of objects in that massive section of space.

That travel time could be helped by the development of a more effective nuclear electric propulsion system, which could shave up to 2 years off it even with a heavier payload than currently planned for Persephone. Such a system has been described but might not be available for the planned 2031 launch date for Persephone on board an SLS rocket.

Fraser discusses the longevity of spacecraft, which will definitely be a consideration for any future missions to Pluto.

Persephone will take a suite of sensors, no matter its propulsion system, which can be “brought to bear on any and every object encountered during the mission,”. According to the flight plan, that would include Jupiter and its moons. These sensors include cameras, spectrometers, radar, magnetometers, and altimeters to meet the mission’s necessary science objectives.

A critical differentiator for the mission is that it is designed to be an orbiter rather than a flyby. According to the authors, much of the data needed to be collected would be infeasible with the short period a flyby would provide with the system. An orbiter would be able to stick around and collect data over the three-year period about both Pluto and Charon, including their active surface dynamics.

This proposal is just one of many mission proposals to the outer planets seeking further funding, and a preliminary estimate of $3bn puts it in the higher range of those missions. But if it is funded in some capacity, it could provide answers to the questions that New Horizons posed, even if it would take several decades to reach them.

Learn More:
Howett et al – Persephone: A Pluto-system Orbiter and Kuiper Belt Explorer
UT – The (Dwarf) Planet Pluto
UT – NASA’s New Horizons Mission Still Threatened
UT – New Horizons is Funded Through the Decade. Enough to Explore Another Kuiper Belt Object

Lead Image:
Graphic of Pluto being visited by Persephone and all the different questions the mission could answer.
Credit – Howett et al.

The post A New Mission To Pluto Could Answer the Questions Raised by New Horizons appeared first on Universe Today.

If you were lucky enough to observe a total eclipse, you are certain to remember the halo of brilliant light around the Moon during totality. It’s known as the corona, and it is the diffuse outer atmosphere of the Sun. Although it is so thin we’d consider it a vacuum on Earth, it has a temperature of millions of degrees, which is why it’s visible during a total eclipse. According to our understanding of black hole dynamics black holes should also have a corona. And like the Sun’s corona, it is usually difficult to observe. Now a study in The Astrophysical Journal has made observations of this elusive region.

For an active black hole, it’s generally thought that there is a donut-shaped torus of gas and dust surrounding the black hole, in which there is an accretion disk of heated material aligned along the rotational plane of the black hole. Streaming from the polar regions of the black hole are jets of ionized gas speeding away at nearly the speed of light. This model would explain the various types of active galactic nuclei (AGNs) we observe, since the orientation of the black hole relative to us changes the appearance of the AGN.

According to the model, the innermost region of the accretion disk should be a superheated region at near vacuum density, which streams into the black hole. It is a corona like the Sun’s, but instead of millions of degrees, it has a temperature of billions of degrees. But because it’s so diffuse, its light is overwhelmed by the light of the accretion disk.

Diagram of the polarization behavior of obscured black holes. Credit: Saade, et al

In this new study, the team used a trick similar to observing the Sun’s corona during a total eclipse. The orientation of a black hole relative to us means that for some black holes the torus of gas and dust obscures our view of the accretion disk region, while for other black holes we can see the disk directly. These are known as obscured and unobscured black holes. The obscured black holes are similar to an eclipsed Sun, since the light of the accretion disk is blocked from view. Unfortunately, so is the black hole’s corona. But the corona is so hot that it emits extremely high-energy X-rays. These X-rays can scatter off material in the torus and reflect into our line of site.

Using data from NASA’s Imaging X-ray Polarimetry Explorer (IPXE), the team gathered data on a dozen obscured black holes, including Cygnus X-1 and X-3 in the Milky Way, and LMG X-1 and X-3 in the Large Magellanic Cloud. They were not only able to observe scattered X-rays from the coronas of these black holes, they were also able to detect a pattern among them. Based on the data, the corona surrounds the black hole in a disk similar to the accretion disk, rather than surrounding the black hole in a sphere similar to the Sun’s corona.

Research such as this will help astronomers refine our models of black holes. It will also help us better understand how black holes consume matter and power the AGNs we observe in distant galaxies.

Reference: Saade, M. Lynne, et al. “A Comparison of the X-Ray Polarimetric Properties of Stellar and Supermassive Black Holes.” The Astrophysical Journal 974.1 (2024): 101.

The post Astronomers Map the Shape of a Black Hole's Corona for the First Time appeared first on Universe Today.

Readers give higher ratings to AI-generated poetry than the works of poets such as William Shakespeare, Walt Whitman and Emily Dickinson – perhaps because they often have more straightforward themes and simpler structure

With the help of a ruby cube and two laser beams, researchers made one ray of light cast a shadow when illuminated by the other

Despite the fact that our universe is old, cold, and well past its prime, it’s not done making new galaxies yet.

Galaxy formation first got started when our universe was only a few hundred million years old. In those dark ages the first stars gathered enough material to trigger nuclear fusion and ignite. Slowly over time those clumps of stars found each other and began to build the first young protogalaxies. 

Over time those protogalaxies accumulated more material and merged together to quickly grow to become the massive galaxies that sprinkle throughout the universe today.

But galaxies are more than clumps of stars and gas. They are also deep wells of dark matter, which is the invisible substance that makes up the most of the mass of every object in the universe. To make a galaxy you really start with an accumulation of dark matter. That forms the gravitational bedrock for normal matter to gather onto and start forming stars.

The accumulation of dark matter really only happened in the very early universe, and long ago shut off. But those concentrations of dark matter remain today. Evidence from simulations and observations tells us that normal matter is still finding those pockets and triggering fresh rounds of star formation. That means while the seeds of galaxies were only laid down once, new accumulations of matter are still lighting up in the present day cosmos.

It is true that we are well past the peak of star formation and the heyday of galaxy assembly. That epoch came and went over 10 billion years ago. And far into the future our universe will expand so much that this process will slow down and eventually stop. But the universe isn’t done yet. For now, we can still enjoy a universe full of galaxies and knowing that new ones are still coming on the scene.

The post Yes, Virginia, The Universe is Still Making Galaxies appeared first on Universe Today.

The New Zealand Astrophotography Competition showcases and recognizes some of the most stunning images of the southern hemisphere’s night sky. This year, photographers from across New Zealand have captured some incredibly breathtaking skyscapes such as amazing auroras, stunning images of our Solar System, and deep-sky marvels.

Universe Today was proud to be part of this year’s competition, as our own Fraser Cain was one of the judges.

The overall winner in the competition is a gorgeous view of the Aurora Australis, above, by photographer Tom Rae. Rae said he captured this image during the “once in a lifetime” geomagnetic storm in May of 2024, showing the Milky Way arching over the dramatic landscape of Aoraki Mount Cook National Park. This image also won the “Aurora” category.

The other categories in the competition include Deep Sky, Solar System, Dark-Sky Places, Timelapse, and new this year are Smartphone Images and a People’s Choice Award, chosen by the public.

There’s also a Nightscape category, and the winner –again — for this category is Tom Rae, showing the bowed Milky Way over a sharp ridge in Aoraki Mount Cook National Park.

“The Ridge” by Tom Rae, winner of the Artistic/Nightscape category of the 2024 New Zealand Astrophotography Competition. Credit and copyright: Tom Rae.

“This image is one of my biggest astrophotography accomplishments to date,” Rae explained on NZ Astrophotography Competition website, “and the largest panorama I’ve ever captured, with the full resolution image containing over a billion pixels from 62 images stitched together.”

Deep Sky “First Amateur Detection of Light Echoes from 19th-Century Great Eruption of Eta Carinae” by Rolf Wahl Olsen in the Deep Sky category of the 2024 New Zealand Astrophotography Competition. Credit and copyright: Rolf Wahl Olsen.

NZ astrophotographer Rolf Wahl Olsen is no stranger to Universe Today readers, as we’ve featured several of his photos for years. Olsen outdid himself with this deep sky photo of Eta Carinae.

“This is the first amateur image of light echoes from the 19th-century Great Eruption of Eta Carinae,” Olsen explained. “These light echoes have been detected by the Hubble Space Telescope and from large observatories such as the CTIO 4m telescope, but this is the first time that amateur images reveal these transient features.

Olson said his other first amateur detection of light echoes from supernova SN1987a inspired an attempt to try looking for the fainter echoes near Eta Carinae. You can read more about this effort on the NZ Astrophotography website and also at Olsen’s website.

Solar System “Solar Fury” by Navaneeth Unnikrishnan won the Solar System Category of the 2024 New Zealand Astrophotgraphy Competition. Credit and copyright: Navaneeth Unnikrishnan.

Navaneeth Unnikrishnan captured this stunning view of the full disk of the Sun. Using an H-alpha filter reveals the Sun’s dynamic surface and massive prominences. “A reminder of the incredible power and beauty just beyond our skies,” said Unnikrishnan.

Dark Sky “Endurance” by Abby Keith won the Dark Sky Places category of the 2024 New Zealand Astrophotgraphy Competition. Credit and copyright: Abby Keith.

Abby Keith captured this stunning dark sky photo while on a five-day hike in New Zealand’s in Fiordland National Park. The view shows Lake Mackenzie, a sub-alpine lake on the Routeburn Track, which is one of New Zealand’s Great Walks.  

This panoramic image consists of 16 images for the foreground and 38 images for the sky.

“This image is the hardest one I’ve had to work for,” Keith explained. Carrying a 20-plus kg pack was worth it, however, as there were perfect conditions to capture this view.

Smartphone “Lake Aviemore aurora” by Ian Griffin won the Smartphone category in the 2024 New Zealand Astrophotgraphy Competition. Credit and copyright: Iam Griffin.

This image was was also taken during the famous geomagnetic storm of May 12, 2024. Griffin called it “one of the most epic auroral storms I have ever seen. As my main digital cameras snapped away, I decided to see what my Iphone could do; I was blown away by the results!”

So are we! For more great astrophotos, check out Griffin’s website.

People’s Choice “Father and Son Magic” by Grant Birley won the People’s Choice Award in the 2024 New Zealand Astrophotgraphy Competition. Credit and copyright: Grant Birley.

New this year for this competition is the People’s Choice Award, where after short-list winners were announced, online voting was opened for the public to choose their favorite images. This beautiful and heartfelt image is definitely worthy of being a favorite. You can see more of Birley’s images on Instagram.

Timelapse

This breathtaking timelapse shows mountains rotating against the backdrop of the stars, instead of the usual view of the stars moving. This work was submitted by Last Quarter Photography on YouTube.

You can see all the winners, runners-up and highly commended images and videos at the NZ Astrophotography Competition website.

New Zealand Astrophotography Competition This is New Zealand’s leading annual astrophotography competition and it is run jointly by the Royal Astronomy Society of New Zealand (RASNZ) and the Auckland Astronomical Society. Along with Fraser Cain, the other judges this year were Judy Schmidt  — another name well-known to Universe Today readers for her imaging editing and cosmic creativity, and Dylan O’Donnell who operates the YouTube channel “Star Stuff.” 

Below is a video of all the short-list entries from this year’s competition.

The post Our Breathtaking Cosmos: New Zealand Astrophotography Winners Announced appeared first on Universe Today.

At the centre of most galaxies are supermassive black holes. When they are ‘feeding’ they blast out jets of material with associated radiation that can outshine the rest of the galaxy. These are known as quasars and they are usually found in regions where huge quantities of gas exist. However, a recent study found a higher than expected number of quasars that are alone in the Universe. These loners are not surrounded by galaxies nor a supply of gas. The question therefore remains, how are they shining so brightly. 

A quasar or ‘quasi-stellar’ object as they are more formally known are among the most powerful and energetic objects in the Universe. They are usually powered by a supermassive black hole at the centre of a galaxy. Matter gets drawn toward the black hole by gravity and as it does, it spirals in forming an accretion disk. It is here that friction and gravitational forces heat material to extremely high temperatures emitting intense light and radiation that can outshine the light from all the stars in the galaxy put together. 

This is an artist’s illustration of a supermassive black hole that is inside the dust-shrouded core of a vigorously star-forming “starburst” galaxy. It will eventually become an extremely bright quasar once the dust is gone. New research shows that the object, discovered in a Hubble deep-sky survey, could be the evolutionary “missing link” between quasars and starburst galaxies. The dusty black hole dates back to only 750 million years after the big bang. NASA, ESA, N. Bartmann

The team of astronomers used NASA’s James Webb Space Telescope to explore 5 distant ancient quasars. They are thought to have formed between 600 and 700 million years after the Big Bang and are a billion times more massive than the Sun. They punt out so much energy that they are more than a trillion times brighter than our local star! 

The objects are 13 billion light years away but due to their extreme luminosity their light can be detected across the cosmos. The real surprise though is that they have been found in an unexpected variety of different environments. The ‘quasar fields’ as they are known include areas of space  crowded with galaxies as the models forecast. The others though seem to be isolated, drifting through space with only a few stray galaxies nearby. 

Using the James Webb Space Telescope between August 2022 and June 2023 multiple images were taken of each quasar field to produce a mosaic. The images were captured in multiple wavelengths and were stitched together provided a complete picture of the region of space around each quasar. Using this approach, the team could determine if the light was from a neighbouring galaxy or from the central quasar. 

Artist impression of the James Webb Space Telescope

The discovery flies in the face of quasar models that usually places them in host galaxies with a plentiful supply of gas and dust to keep them fed. Finding quasars floating in voids has left astronomers scratching their heads to understand and modify the theories. It is of course possible the host galaxies are just not visible, perhaps they are just shrouded by dust. 

When the quasars formed, the Universe would have been full of filaments of dark matter. The presence of the matter would attract gas and dust through gravitational interactions. It is from this material that the studied quasars would have formed. However the curiosity is that they would have had to grow at an incredible rate through accretion to achieve the luminosity seen just a few hundred years after the Big Bang. Further observations are needed of the quasar fields to try and identify the true nature of the area they exist within to truly understand their nature. 

Source : Astronomers detect ancient lonely quasars with murky origins

The post Why are Some Quasars So Lonely? appeared first on Universe Today.

Driverless cars can now do doughnuts and drift like stunt drivers, skidding sideways around corners while maintaining control, which might help the cars recover from dangerous situations

Elon Musk’s SpaceX is preparing for the sixth test flight of Starship, the world's most powerful rocket. It aims to conduct the launch as early as 18 November. Here’s everything we know so far

An 11-page document that’s attributed to a Pentagon whistleblower has provided new cases in the controversy over unidentified anomalous phenomena — also known as UAPs, unidentified flying objects or UFOs.

The document, released today in conjunction with a House subcommittee hearing on UAPs, lays out details about what’s said to be a special access program called Immaculate Constellation. It accuses officials in the federal government’s executive branch of a “criminal conspiracy” that has been managing issues surrounding UAPs and evidence for non-human intelligence “without congressional knowledge, oversight or authorization for some time, quite possibly decades.”

Over the past few years, the Department of Defense has become more open to discussing UAP reports publicly, while insisting that there have been no substantiated reports of alien visitations. During today’s hearing, lawmakers called on the Pentagon to be more transparent in its investigations.

“It is clear, from my experience and what I’ve seen, that there is something out there,” said Rep. Andy Ogles, R-Tenn. “The question is, is it ours? Is it someone else’s? Or is it otherworldly? … We must know, and anyone who prevents us from gaining access to that information, I would consider that criminality, because we have U.S. personnel who may very well be in harm’s way.”

The document claims that the Immaculate Constellation program has imagery and other data relating to encounters with a variety of anomalous objects. “From 1991 to 2022, the most common UAP shapes reported in this [U.S. government] dataset were spheres/orbs, discs/saucers, ovals/tic-tacs, triangles, boomerang/arrowhead, and irregular/organic,” it said. The irregular objects were described as having a “floating brain” or “jellyfish” appearance.

Michael Shellenberger, an author and journalist who received the document from the purported whistleblower, said he verified the source’s credentials and assured lawmakers that the document was authentic. He also said he’s continuing to gather reports from other sources.

“Since my reporting on this Immaculate Constellation last month, another source came forward,” Shellenberger said. “He told me that they saw a roughly 13-minute-long, high-definition, full-color video of a white orb UAP coming out of the ocean approximately 20 miles off the coast of Kuwait. It was filmed from a helicopter. Then halfway through the video, the person said, the orb is joined by another orb that briefly comes into the frame from the left before rapidly moving again out of the frame.”

Shellenberger said there may be “hundreds, maybe thousands” of UAP reports in the Immaculate Constellation database.

Mick West, a retired software engineer who specializes in analyzing UAP reports, was generally skeptical of the claims made during the hearing, which was conducted jointly by two subcommittees under the aegis of the House Oversight Committee. Nevertheless, West was intrigued by the purported whistleblower report — and said the Pentagon’s All-Domain Anomaly Resolution Office, or AARO, should follow up.

“The UFO document discussed in congressional testimony today contains descriptions of some interesting-sounding videos,” West said in a posting to the X social-media platform. “If these exist, I urge @DoD_AARO to make as many of these videos public as possible and share their analysis so we can get some clarity ASAP.”

In addition to Shellenberger, the witnesses at today’s hearing included retired Navy Rear Adm. Tim Gallaudet, who served as the acting administrator of the National Oceanic and Atmospheric Administration during the Trump administration; Luis Elizondo, a former intelligence official who is now an advocate for UAP disclosure; and Mike Gold, a former NASA associate administrator who was a member of NASA’s independent UAP study panel and is now chief growth officer at Redwire.

Witnesses at the UAP hearing included, from left, Tim Gallaudet, Luis Elizondo, Michael Shellenberger and Mike Gold. (Credit: House Oversight Committee via YouTube)

In advance of the hearing, Gallaudet came in for some strong criticism from Sean Kirkpatrick, who was in charge of AARO in 2022-2023 and is now chief technology officer for defense and intelligence programs at Oak Ridge National Laboratory in Tennessee. “Mr. Gallaudet is clearly still bitter that I didn’t hire him into AARO when he came looking for a job,” Kirkpatrick said in a statement distributed on X. “His predisposed tendencies for conspiracies without evidence made him unsuitable for a job that required objectivity and evidence-based reason.”

Kirkpatrick and others involved in the UAP debate have suggested that the likeliest explanations for anomalous aerial sighting have to do with advanced technologies that are being secretly employed by rival nations, including Russia and China. But questions about potential alien intrusions, secret crash retrievals and exotic technologies repeatedly came up during the hearing.

In response to such questions, Gallaudet said he believed some of the reports about UAPs could be attributed to non-human higher intelligence. Elizondo agreed. “Although much of my government work on the UAP subject still remains classified, excessive secrecy has led to grave misdeeds against loyal civil servants, military personnel and the public — all to hide the fact that we are not alone in the cosmos,” Elizondo said.

In contrast, Gold declined to weigh in definitively on questions about extraterrestrials. “I just don’t know,” he said. “I think we must be modest in our assumptions that we’re looking for intelligence that could be biological. It might not.”

For example, Gold said, some UAPs may be controlled by artificial intelligence. “We assume that all intelligence would be like us, and every time we look out in the universe, we are humbled relative to what we don’t know, in terms of the forms of intelligence and what it may take,” he said. “l probably can’t answer your question, but I think the ultimate answer is going to surprise us all.”

The witnesses and the lawmakers seemed unanimous in their support for greater transparency about UAP sightings. Congress is currently considering legislation that would strengthen current requirements for UAP disclosure and whistleblower protection.

Rep. Jared Moskowitz, D-Fla., hinted that more information may be forthcoming when Donald Trump returns to the White House. “This has been bipartisan, bicameral,” Moskowitz said. “As we get into a new administration, the president-elect has talked about opportunities to declassify information on UAPs, and I hope he lives up to that promise.”

The post Congressional Hearing Fuels Fresh Debate About UFOs appeared first on Universe Today.

One of the most challenging aspects of astrobiology and the Search for Extraterrestrial Intelligence (SETI) is anticipating what life and extraterrestrial civilizations will look like. Invariably, we have only one example of a planet that supports life (Earth) and one example of a technologically advanced civilization (humanity) upon which to base our theories. As for more advanced civilizations, which statistically seems more likely, scientists are limited to projections of our own development. However, these same projections offer constraints on what SETI researchers should search for and provide hints about our future development.

In a series of papers led by the Blue Marble Space Institute of Science (BMSIS), a team of researchers examines what Earth’s level of technological development (aka. “technosphere”) will look like in the future. In the most recent installment, they offer a reinterpretation of the Kardashev Scale, which suggests that civilizations expand to harness greater levels of energy (planet, host star, and galaxy). Instead, they suggest that the Kardashev Scale establishes upper limits on the amount of stellar energy a civilization can harness (a “luminosity limit”) and that civilizations might circumvent this by harnessing stellar mass directly.

As with the previous study in this series, the research was led by Jacob Haqq-Misra, the Senior Research Investigator at the Blue Marble Space Institute of Science. He was joined by George Profitiliotis, an Affiliate Research Scientist at the BMSIS and a Research Member of the Working Group on SETI and Law at the International Institute of Space Law (IISL), and Clement Vidalb, a researcher with the Center Leo Apostel (CLEO) at the Free University of Brussels. The paper “Projections of Earth’s Technosphere: Luminosity and Mass as Limits to Growth” is being reviewed for publication in Acta Astronautica.

Energy consumption estimated in three types of civilizations defined by the Kardashev Scale. Credit: Wikimedia Commons

The Kardashev Scale, named after Soviet-Russian astrophysicist and radio astronomer Nikolai Kardashev (1932 – 2019), was first proposed in his seminal paper, “Transmission of Information by Extraterrestrial Civilizations,” released in 1964. In it, Kardashev suggested what types of radio frequencies (and at what energies) scientists should search for to discern possible transmissions of an extraterrestrial civilization (ETC). In keeping with the idea that there may be civilizations billions of years older than humanity, he reasoned that these civilizations could harness levels of energy beyond human capabilities.

To characterize the level of an ETC’s development, Kardashev proposed a three-level scale based on the amount of energy they could harness. This included:

• Type I – Planetary Civilizations: ETCs that have developed the means to harness and store all of their home planet’s energy, an estimated 4×1019 erg/sec.
• Type II – Stellar Civilizations: ETCs that have evolved to the point where they can harvest all the energy emitted by their star – 4×10³³ erg/sec.
• Type III – Galactic Civilizations: ETCs able to harness the energy of an entire galaxy – 4×1044 erg/sec.

However, this scale reflected the assumption that civilizations and their energy needs will grow exponentially. This is in keeping with observations of humanity’s own “technosphere,” which refers to the human-made infrastructure, machinery, communications, and other indications of technological activity (aka “technosignatures”). Basically, it reflects our limited perspective when it comes to the kinds of behaviors advanced ETCs would exhibit. As Haqq-Misra told Universe Today via email:

“Earth is our only known example of a planet with technology, so the search for extraterrestrial civilizations must begin by thinking about how to search for analogs to Earth’s technosignatures today and possible technosignatures that could arise in Earth’s future. We should also try to stretch our minds to consider other, non-terrestrial, and more exotic possibilities, but even such imaginative possibilities will always either begin with (or contrast with) what we know is possible based on existing or known physics on Earth.”

Artist’s impression of a Dyson Sphere, a proposed alien megastructure that is the target of SETI surveys. Finding one of these qualifies in a “first contact” scenario. Credit: Breakthrough Listen/Danielle Futselaar

Traditional applications of the Kardashev Scale predict that growth will be exponential and have even considered how this could give rise to a civilization capable of utilizing the energy output of all stars in the Universe – a Type IV Cosmic Civilization! This application has motivated many searches for civilizations that have reached these scales of vast energy utilization, as indicated by megastructures (e.g., Dyson Spheres, Clarke Bands, etc.) and other advanced technospheres. For their study, Haqq-Misra and his colleagues took a different approach:

“Our study re-examines these assumptions by noting that civilizations can follow different trajectories for their expansion in space and their energy consumption. This involves tradeoffs between ‘exploration’ and ‘exploitation,’ and there are many possibilities for how a civilization might develop along these two dimensions. Some civilizations may prioritize exploration in physical distance without ever needing to expand their energy consumption to Kardashev Type I or Type II scales. Other civilizations may focus on exploitation and increase their energy use more locally. Some civilizations may attempt to find an optimal balance between exploration and exploitation.

“We also point out that the Kardashev scale is better considered as a theoretical limit to a civilization that utilizes stellar energy (luminosity). Rather than describing a trajectory that advanced civilizations will follow, the Kardashev scale is the uppermost limit for a civilization’s energy use, as it relates to expansion in physical distance, but a limit that may never actually be achieved due to thermodynamic efficiency limits. In other words, the Kardashev scale describes an upper-limit to the tradeoffs between exploration and exploitation, and a civilization that is dependent on stellar luminosity for its energy needs will always fall below the energetic and spatial limits described by the Kardashev scale.”

The scenario Haqq-Misra and his colleagues proposed presents some new and interesting possibilities for advanced civilizations. For example, suppose humanity ever reaches the limit of how much energy it can harness from our Sun. In that case, it may not choose to explore and settle other star systems (with the intent of harnessing the energy of more planets and more stars). Instead, they may turn to harvesting stellar mass itself.

Illustration of a white dwarf accreting mass by stripping its non-degenerate companion. Credit: ESO/Kornmesser

“Civilizations like this that consume stars, which we call ‘stellivores,’ would be able to expand in energy use beyond the luminosity limits of the Kardashev scale,” said Haqq-Misra. “We are not at this level as a civilization on Earth yet, but we can at least think about the possibility that harvesting mass and converting it into energy (as Einstein’s famous equation describes) provides a way for a civilization to reach energy use scales beyond those envisioned by the Kardashev scale.”

Like all projections on humanity’s future development, this study also has implications for future SETI surveys. This is in keeping with the assumption that ETCs in our galaxy would be older and more advanced than humanity at this point. It’s also consistent with the principle that “if we can conceive of it, someone else has probably done it already.” As Haqq-Misra explained, future SETI surveys should examine “accreting binaries,” closely orbiting binary stars with mass flowing from one star to another.

Maqq-Misra and his colleagues recommend that scientists observe accreting binaries to search for abnormal behavior, which could indicate technological activity:

“If some civilizations actually do evolve into stellivores, then some of these may look like such accreting binary star systems. We cannot claim that all, or even most, accreting binaries are actually technological civilizations, but we also cannot rule out the possibility that some of them could in fact be technological. It is worth keeping our minds open and actually searching for such evidence of advanced and exotic civilizations rather than ruling them out before we look.”

Further Reading: arXiv

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Mobile phones could be the key to a cheaper and more reliable way of tracking animals for ecology and conservation research, according to a new study.

The mega-coral measures 34 metres by 32 metres – making it larger than a blue whale – and it is thought to be three centuries old

Navigating the harsh terrain of other rocky worlds has consistently been challenging. The Free Spirit campaign unfortunately failed in its goal to will the plucky Martian rover out of the morass it found itself in, despite two years of continual effort from some of the world’s best engineers. To combat this difficulty, other engineers have turned to alternative propulsion methods, and a team of researchers in the EU have done just that for their work on an autonomous mining robot. They decided to use an Archimedes screw as their primary propulsion method.

The team has already successfully tested various prototype iterations of their miniaturized mining robot. More recently have released a paper that detailed a mobility platform based on four individually controlled Archimedes screws that could be useful for more than just mining underground.

As with most engineering projects, they started with a computer model, which resulted in a CAD model that the team tested on different terrain. They weren’t the first ones to think of using an Archimedes screw as a driving mechanism. Existing research has pointed out that it is not the most efficient on some terrains. However, it can navigate almost all terrains to at least some degree.

The work described in the paper was part of the ROBOMINERS project, supported by the EU.
Credit – ROBOMINERS YouTube Channel

Kinematics models are critical to the development of any robot, and one with a relatively obscure propulsion system is no exception. Since Archimedes screws can be modeled from any observational angle, coordinating the operation of each of the four independent screws to align correctly to the desired direction required some complex modeling that was eventually hosted as part of the control algorithm on board a computer seated on top of the mobile platform.

Another part of the control algorithm required the robot to understand how it was orientated, and to do that, the team developed an integrated network of sensors. These ranged from time of flight positioning systems, which allowed the robot to gauge the distance to an object, to force sensors on the screws themselves that would ensure they wouldn’t over-torque and burn out their drive motors.

Once the sensors were selected and the preliminary control code was written, it was time to put it to a real environmental test. The team built a physical prototype, partly out of 3D-printed parts, and set about moving it about on various surfaces. The drive system worked well on snow, sand, frozen ground, and mud. However, it was mainly used to traverse level surfaces rather than the more complicated slopes that it might encounter in some environments, such as Mars. 

Fraser discusses how we might use robots to explore the Moon.

That is not to say the system cannot adapt to slopes – just that there is more work to be done. ROBOMINERS, the EU project focused on building an autonomous mining robot, is looking to complete its final prototype soon, and the results of the drive platform testing shown in this latest paper will help contribute to that. Someday, it might contribute to a similar robot on the moon or Mars.

Learn More:
Gkliva et al – A Multi-Terrain Robot Prototype With Archimedean Screw Actuators: Design, Realization, Modeling, and Control
UT – NASA Tests a Robotic Snake That Could Explore Other Worlds
UT – Snake Rovers Might be the Best Way to Explore the Surface and Tunnels on Mars
UT – NASA Redoubling Efforts to Contact Spirit

Lead Image:
Prototype of the screw-driven robot on leafy ground.
Credit – Gkliva et al.

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Mars has been a fascination to us for centuries. Early observations falsely gave impressions of an intelligent civilisation but early visiting probes revealed a stark, desolate world. Underneath the surface is a few metres of water ice and a recent study by NASA suggests sunlight could reach the layer. If it does, it may allow photosynthesis in the meltwater. On Earth this actually happened and biologists have found similar pools teeming with life. 

The exploration of Mars by space probes began in the 1960’s. It began with the Soviet Union Mars 1 and NASA’s Mariner mission and was soon followed by the well known Viking landers in 1976. They were the first missions to test surface material for signs of life. The Mars Pathfinder mission took along the Sojourner rover and was followed by Spirit and Opportunity rovers after the turn of the century. Curiosity rover was among the latest of the visitors along with Perseverance and China’s Tianwen-1. The focus of later missions has been the hunt for water and analysis of the climate and geology of the planet. This was not only to understand the conditions as the planet evolved but to pave the way for human exploration. 

The Viking 1 lander was the first to capture a real selfie. This is a mosaic of high-resolution images of Viking 1 at Chryse Planitia. Image Credit: NASA/JPL.

To date, there has been no evidence of life on Mars. The question has intrigued us for decades though. Of all the planets in the Solar System, Mars is the most likely place to have once harboured primitive life, chiefly due to the discovery of liquid water in the distant past. Evidence of ancient dried river beds has been found across the planet with mineral deposits indicating that Mars was once warmer, wetter and potentially far more habitable. Even organic molecules have been discovered by the Curiosity and Perseverance rovers but researchers continue to hunt for evidence (past or present) of microbial life. 

Mars, Credit NASA

A team of researchers from NASA have published a paper articulating their use of computer modelling to help the search. They have shown that sunlight can shine through the Martian water ice, perhaps even enough for photosynthesis to occur in shallow pools of meltwater. 

There are two types of ice on Mars, frozen water and frozen carbon dioxide. The study explored water ice which had mostly formed as snow had fallen on the surface during a Martian ice age millions of years ago. The team believe that the key to the study are the dust particles that obscure light reaching the deeper layers of ice. They suggest that sunlight will warm the dark dust more than surrounding ice and then cause ice to warm and melt. Some scientists believe that ice at the surface cannot melt due to the thin dry atmosphere causing it to turn straight to a gas. This won’t apply to the ice deeper in the surface layer. 

Almost pure water ice is seen in the ejecta surrounding this impact crater (8 meters in diameter), which formed in 2008. The only reason we can see ice at the surface here is because this crater is so young. As time passes, the ice will all sublimate and no longer be present at the surface. Image Credit: High Resolution Imaging Science Experiment camera, NASA/JPL-Caltech/University of Arizona.

Such a process has been observed on Earth where dust heats ice, melts and allows the dust to sink. Over time, the dust particles will stop sinking through the ice but still generate enough heat to melt the ice and create tiny voids. It is here that thriving ecosystems have been found hosting simple forms of life. 

The paper published in Nature Communications Earth & Environment, suggests the dusty ice can produce enough light at depths up to 3 metres to allow photosynthesis to occur. The subsurface pools of meltwater are protected from evaporating by the ice above. It also provides some protection from radiation too providing a possibly habitable environment for simple forms of life. The authors suggest the areas would likely form in the Martian tropics between 30 and 60 degrees latitude in both hemispheres. 

Source : Could Life Exist Below Mars Ice? NASA Study Proposes Possibilities

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Researchers have developed a simple model system that can be used to break down fibrils -- the cause of numerous disorders including Alzheimer's and Parkinson's disease -- into their constituent single units or liquid droplets.

An asteroid struck Mars 11 million years ago and sent pieces of the red planet hurtling through space. One of these chunks of Mars eventually crashed into the Earth and is one of the few meteorites that can be traced directly to Mars. This meteorite was rediscovered in a drawer at Purdue University in 1931 and therefore named the Lafayette Meteorite. During early investigations of the Lafayette Meteorite, scientists discovered that it had interacted with liquid water while on Mars. Scientists have long wondered when that interaction with liquid water took place. Scientists have recently determined the age of the minerals in the Lafayette Meteorite that formed when there was liquid water.