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Researchers have published a programmable framework that overcomes a key computational bottleneck of optics-based artificial intelligence systems. In a series of image classification experiments, they used scattered light from a low-power laser to perform accurate, scalable computations using a fraction of the energy of electronics.

Researchers have published a programmable framework that overcomes a key computational bottleneck of optics-based artificial intelligence systems. In a series of image classification experiments, they used scattered light from a low-power laser to perform accurate, scalable computations using a fraction of the energy of electronics.

All living creatures use only the left or right-handed forms of certain molecules, and now we might understand why

Evidence suggests that cynicism is bad for your health. Neuroscientist Jamil Zaki describes the three ways to conquer your inner cynic to boost your well-being

Scientists discovered the Andromeda galaxy, known as M31, hundreds of years ago, and around a century ago, we realized that it had negative radial velocity toward the Milky Way. In other words, eventually, the two galaxies would merge spectacularly. That has been common knowledge for astronomers since then, but is it really true? A new paper from researchers at the University of Helsinki looks at several confounding factors, including the gravitational influence of other galaxies in our local group, and finds only a 50% chance that the Milky Way will merge with the Andromeda galaxy in the next 10 billion years. 

That seems like a pretty big thing to get the physics wrong on. So, how did the authors come to that conclusion? They accounted for a problem that has been popularized in media as of late – the three-body – or in this case, four-body – problem. And with that problem comes a lot of uncertainty, which is why there’s still a 50% chance that this huge event might still happen. 

Thinking of Andromeda and the Milky Way in isolation doesn’t account for the other galaxies in what we know as the “Local Group.” This comprises approximately 100 smaller galaxies at various orientations, distances, and speeds. The largest of the remaining galaxies is the Triangulum galaxy, M33, which is about 2.7 million light-years away and consists of upwards of a mere 40 billion stars. That’s about 40% of the approximately 100 billion stars in the Milky Way but a mere 4% of the nearly 1 trillion stars estimated to exist in Andromeda. Still, they would have their own gravitational pull, contorting the simplistic dynamic between Andromeda and the Milky Way.

Fraser explains some of the orbital mechanics around Andromeda’s motion.

Further confounding that dynamic is the Large Magellanic Cloud, which is either the second or third closest galaxy to our own at a distance of only 163,000 light years. This is slightly larger than the Milky Way’s diameter, at 105,700. It also houses around 20 billion stars, so while it’s even less massive than M33, it still exerts a hefty gravitational pull.

The authors accounted for the gravitational pull of both of those other galaxies in their calculations of the paths of the Milky Way and Andromeda over the next few billion years. They found that the complicated dance of astronomical giants could potentially result in a scenario where the two galaxies don’t merge. However, there was another significant factor in their calculations: uncertainty.

Scientists never like uncertainty. In fact, much of their research tries to place bounds on certain parameters, like the rotational speed of galaxies or the distances between them. Unfortunately, despite their proximity, there are many uncertainties surrounding the four galaxies used in the study, and those uncertainties make precise calculations of the effects of their gravitational and rotational pull difficult.

Fraser discusses what stars, if any, we can see in Andromeda.

Developing estimates rather than concrete numbers is one-way scientists often deal with uncertainty, and in this case, that estimate fell right at the 50% mark in terms of whether or not the two galaxies would collide. However, there is still a lot of uncertainty in that estimate, and plenty more confounding factors, including the other galaxies in the local group, will influence the final outcome. Ultimately, time will help solve the mystery, but that is a very long time on the scale of galaxy mergers. If it happens at all, a merger between the Milky Way and Andromeda will happen long after our own Sun has burnt out, and humans will either die out with it or find a way to expand to new stars. And if, at that point, we get easy access to an additional galaxy’s worth of resources, it would be all the better for us.

Learn More:
Sawala et al. – Apocalypse When? No Certainty of a Milky Way — Andromeda Collision
UT – Are Andromeda and the Milky Way Already Exchanging Stars?
UT – What a Mess. When the Milky Way and Andromeda Merge, it’ll Look Like This
UT – We Might Be Able to Measure Dark Energy Through the Milky Way’s Collision With Andromeda

Lead Image:
This illustration shows a stage in the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. In this image, representing Earth’s night sky in 3.75 billion years, Andromeda (left) fills the field of view and begins to distort the Milky Way with tidal pull.
Credit: NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger

The post Are Andromeda and the Milky Way Doomed to Collide? Maybe Not appeared first on Universe Today.

Today was a special day in Capetown: the day I got to visit the site of Boulders on the coast, one of the few breeding sites of a rare species of penguin that I hadn’t seen before: the African Penguin (Spheniscus demersus), also known as the Cape Penguin.

But before that, let’s not forget a few of the local endemic flowers. First, pincushion (Leucospermum sp.)

An aloe (Aloe), another from the garden here.

A Cape Honeysuckle (Tecomaria capensis).

The lovely house where I’m staying is the one to the left with the shiny roof. It looks out over the Indian Ocean, shortly before it joins the south Atlantic to the west, and yesterday we saw a southern right whale (Eubalaena australis) swimming around right below.

Not far away is the fishing village of Kalk Bay, where ships pull in with a piscine haul, seals bask in the sun, and chippies surround the harbor to feed the catch to hungry visitors.

Here is a warning:

I was duly warned, but couldn’t avoid getting about seven feet away from this sleeping beauty, the African subspecies of the Brown Fur Seal (also called the Cape Fur Seal), Arctocephalus pusillus pusillus. As you see from the figure below, there’s also a subspecies that lives and breeds on the tip of SE Australia.

It’s the world’s largest fur seal. This one was sleeping peacefully on the dock:

A close-up of its adorable face. Don’t you just want to kiss it? But don’t–they bite!

The distribution of the two subspecies of this species. See caption for details and credit.

From Wikipedia: “Distribution of the brown fur seal, dark blue: breeding colonies; light blue: nonbreeding individuals.” Figure by Mirko Thiessen, CC BY-SA 3.0, via Wikimedia Commons.

And then. . . on to the penguins!

About the African Penguin. More facts from Wikipedia:

The African penguin is a pursuit diver and feeds primarily on fish and squid. Once extremely numerous, the African penguin is declining rapidly due to a combination of several threats and is classified as endangered. It is a charismatic species and is popular with tourists. Other vernacular names of the species include black-footed penguin and jackass penguin, due to the species’ loud, donkey-like noise (although several related species of South American penguins produce the same sound). They can be found along the coast of South Africa and Namibia.

They have built artificial burrows for the penguins to live and breed in; they look like amphoras cut in half and placed on their side. The explanation for creating these is below:

. . . and, a lovely African penguin. I love its pink eye ring:

A closeup of the face:

A beach full o’ penguins. But Rita, who has been coming here for 20 years or so, says that there used to be four times as many penguins on this beach. A combination of factors, not least among them competition for fish with local fishermen who range widely, has drastically reduced the population size. These wonderful birds are now classified as endangered.

First-year penguins molt their down before they develop their adult feathers (remember this from Antarctica?).  Here are three babies (fed fish by their mom), losing their down.

This chick looks surprised.

And this one looks obstreperious:

A panorama of the beach (click to enlarge):

This penguin carried a stick all the way from the woods above (where the nests are) down into the water. Why? Who knows? Could it be a display?

These penguins have already been fishing and are exiting the water. They swim around a bit in the bay before they come ashore.

These are the artificial penguin nests; they’re in thick shrubbery up above the beach.

Me and my penguin (photo by Rita):

And with more penguins (also by Rita):

There was a shop full of penguin paraphrenalia, but I already have too many penguin-related items and forced myself not to buy anything. But I did admire this penguin made out of discarded plastic utensils and cup lids.

Don’t mess with the penguins!

These next two signs suggest to me (I’m a worrier) that some hapless motorist squashed a penguin at least once in the past.

Check your car! (Photo by Rita.)

In the vegetation near the penguins I saw a rock hyrax (Procavia capensis), locally called the “dassie”.  They are herbivores and are found widely throughout Africa.  Surprisingly, despite its small size it is the land mammal most closely related to the elephant, though whether manatees and dugongs are more closely related to elephants is undecided.

A female chacma baboon (Papio ursinus), hanging around the garbage bins in town. Don’t mess with these primates!

A quick trip to the grocery store, which happens to be Woolworth’s, said to have the best produce in this area.  Ground ostrich meat and extra lean venison (which is a synonym here for antelope) were both purchased for the next two dinners.

Ingredients: “Gemsbock and/or Wildebeest and/or Kudu and/or Hartebeest and/or Eland and/or Impala and/or Springbok and/or Blezbok”—all antelopes. You never know what you bought!

And I took the gang out for fish and chips at Kalky’s in the harbor, a downmarket local favorite. The entrance:

The menu. Remember that one rand is about 6¢ US, so my hake and chips meal, which was quite good, cost about six bucks:

The line, which got quite long, and in front of that the dining room. You pay (cash only) and pick up your order when it’s called.

You would never have gotten a crowd this mixed in the bad old days of apartheid, when people were strictly segregated into four classes: black, white, Indian, and colored (mixtures of black and white). Curiously, Chinese were lumped with the most oppressed class, blacks, while Japanese counted as white.

Hake ‘n’ chips: very good!

Red-winged starling (Onychognathus morio), a species found in East Africa from Ethiopia to South Africa. The underside of its wings are red, but you can’t see that in this photo.

Today: a visit to the Cape Peninsula.

Meanwhile, in Dobrzyn, Hili is on the look-out for her arch-enemies:

A: Where are you going?
Hili: To check whether the hazelnuts are ripe.
A: Why?
Hili: Because when they are squirrels are sometimes coming.

Ja: Gdzie idziesz?
Hili: Sprawdzić, czy orzechy laskowe już dojrzały.
Ja:Czemu?
Hili: Bo wtedy czasem przychodzą do nas wiewiórki.

The cultural effects of the COVID pandemic can still be felt reverberating through society. One of the positive effects, in my opinion, was the sudden boost to remote technology – connecting remotely for meetings and other uses through Zoom or a similar application. This development has been a little controversial, but I think on the whole has been a net positive, especially as we move into the era of voluntary remote connections and hybrid meetings.

Prior to the pandemic having a hybrid or remote meeting was still the exception rather than the rule. We were slowly progressing in this direction, but it was still uncommon and looked upon with suspicion. For example, my wife obtained her PhD through a hybrid online program (partly online, partly in person). This worked well and was very convenient, considering we live in CT and the program is based in Oregon. But she definitely faced some professional headwinds in terms of acceptance of the concept of online learning. At K-12 schools remote learning was essentially not a thing.

While virtual meetings were already a thing, they too were not routine. For me personally, for example, all of my meetings, lectures, rounds, and workshops were in person. There wasn’t even an option to attend remotely. This is despite the fact that we have the technology. Grand rounds, for example, was streamed to an outside location where some of our physicians work so that they could attend.

Clinically there was a lot of discussion about virtual office visits, and again we saw the beginnings of this technology and very tentative explorations. Mostly this was used to provide expert-level consultations to remote areas or local hospitals lacking such experts. For routine use, however, it was non-existent, and there were many bureaucratic obstacles, such as state licensing rules and insurance reimbursement.

Then, of course, COVID hit and the world was forced to do as much as possible remotely. This partly worked and partly failed, based at least partly on infrastructure and execution. Looking back now it seems the K-12 remote learning experience was a bad one. Keep in mind, this was still a complex situation. Many teachers had to say out of work because they tested positive for COVID, so school was going to be negatively impacted no matter what we did. And we don’t know what would have happened if all schools remained open in terms of the pandemic itself. But we definitely did underestimate the negative impact of forced online schooling. But a lot of this was due to the fact that many schools and homes were simply not prepared, and you can’t simply run a class online. The experience has to be designed and optimized for being online.

Now that we are post pandemic, we appear to be settling into the best of both worlds – a hybrid situation where voluntary use of remote presence when appropriate. My hope is, this will continue and we will gain more experience and comfort with remote meetings to gain the advantages while minimizing the disadvantages.

For learning some types of content are actually better online. I attend many lectures remotely, and they are great. You have the slides right on your computer, with a inset picture of the lecturer. You can type questions, or ask them live. I have also given such lectures online, and this too can work very well. However, there are types of classes that don’t work online, those that function more like workshops. If you need a lot of interaction with the audience, Zoom can be a problem. It’s hard to know if someone is paying attention, and it can be challenging to direct questions to individual attendees. Physical presence does have it’s advantages.

For small meetings virtual setups, I think, are optimal. Everyone can see and hear everyone and it’s easy to share desktops and content. Clinically, telehealth is also idea for some types of encounters, but not for others. If all I need to do is talk to my patient, give them orders or prescriptions, and document everything in the chart, telehealth is ideal. If I need to examine them, then they need to come in.

This is why the hybrid situation we are evolving towards is ideal. Even for individual meetings, some people can be present while others attend remotely. I think one thing we learned is that having the option for remote attendance is great to have and is an important way to level the field for everyone. Some patients, for example, have a really hard time physically getting into the office for a visit – they need to arrange transportation, take time off from work or home responsibilities, and navigate with sometimes severe physical limitations. Contrast this to sitting on your couch, or going into a break room at work, and just connecting on your phone for 10 minutes. The convenience and efficiency gain is massive, and leads to better medical care. These same patients have a high risk of no-showing to appointments because they could just not make it in.

For business meetings, conferences, and learning experiences, having the option to attend remotely helps individuals who have child care responsibilities, who would otherwise be at a disadvantage in terms of professional progress.

Not to mention, there is a large environmental benefit to hybrid conferences. If the longest-distance speakers or attendees can attend remotely, that reduces long-distance travel.

What all this means is that we now have an opportunity to move forward from COVID rather than go back. I hope that those parts of the experience that were negative will not dissuade people from continuing to support remote meetings. It should now become routine and normalized to allow for hybrid and remote access to all types of conferences and meetings. Content should be designed to work remotely, as well as in person. The advantages are just too great to ignore and let slip away. This begins with realizing that we are not talking about the forced experience of the pandemic, but a hybrid voluntary experience that is optimized for everyone.

The post Living a Hybrid Life first appeared on NeuroLogica Blog.

We recently reported on how the mountains of data produced by astronomical instruments are “perfect for AI.” We’ve also started reporting on several use cases for different AI algorithms. Now, a team of researchers from the University of Texas has developed a new use case that focuses on discovering the interior makeup of exoplanets by looking at a specific type of star.

That particular kind of star is known as a “polluted” white dwarf. White dwarves are the end stage of stars that are too small to go supernova. After going through a red giant phase, our sun will turn into one in a few billion years. Typically, they only have hydrogen and helium in their upper atmosphere, making them mundane by the standards of stars – unless they happen to be tearing apart one of their planets.

Every once in a while, a white dwarf draws in one of the planets in its solar system, ripping the planet apart in the process. The planet’s interior materials are then absorbed into the star’s outer shell, making them “polluted” with the heavy metals that typically comprise a planet’s interior. 

Another researcher from Boston University details how “polluting” a white dwarf can be translated into an understanding of planetary makeup.
Credit – Kavli Institute for Theoretical Physics

Analyzing those heavy metals in a star’s atmosphere would allow astronomers to understand the makeup of the former exoplanet. As such, finding polluted white dwarves to analyze has been a focal point of exoplanet hunters for some time. However, saying the process is time-intensive is an understatement. Astronomers have to manually check astronomical surveys to find evidence of heavy metals in white dwarves’ atmospheres, and some of those surveys, needless to say, are big.

However, searching for needles in a haystack sounds like the perfect use case for AI. So, researchers at the University of Texas did just that. They developed an algorithm using an AI technique called manifold learning and let the algorithm loose on data from Gaia, ESA’s astrometry mission. They filtered data from around 100,000 white dwarves, which resulted in 375 potentially polluted candidates.

Follow-up observations on those 375 candidates by the Hobby-Eberly Telescope and the McDonald Observatory, both of which are at least partially controlled by UT, showed that the algorithm was 99% correct in detecting the existence of heavy metals in a star’s atmosphere, thereby classifying it as “polluted.” Given the sheer volume of white dwarves in our galaxy, tens of thousands more candidates can likely be found by allowing the algorithm to trawl through other data collected on them.

Fraser discusses the possibilities of habitable planets around white dwarves.

What that means for astronomers is the ability to understand the interior makeup of exoplanets as their host star is ripping them apart. Understanding their interior makeup would allow astronomers to develop models about their chances for harboring life. So, this paper is a step towards developing that astrobiological model and an excellent use case for AI in astronomy. It just so happens to be built on the back of dying planets that might be taking their own form of nascent biospheres with them.

Learn More:
UT Austin – Astronomers Use AI To Find Elusive Stars ‘Gobbling Up’ Planets
Kao et al. – Hunting for Polluted White Dwarfs and Other Treasures with Gaia XP Spectra and Unsupervised Machine Learning
UT – What Can AI Learn About the Universe?
UT – Astronomy Generates Mountains of Data. That’s Perfect for AI

Lead Image:
Artist’s depiction of a star ripping apart a planet.
Credit – NASA, ESSA, Joseph Olmsted (STScI)

The post Astronomers Use Artificial Intelligence To Find Elusive Stars “Gobbling Up” Planets appeared first on Universe Today.

The construction of the Vera C. Rubin observatory has just crossed a major milestone with the successful installation of its 3.5 meter diameter secondary mirror. The observatory is now one step closer to first light in 2025, when it will begin the Legacy Survey of Space and Time (LSST): a mission to repeatedly image the entire sky, at high resolution, to create a time-lapse record of the Universe.

The construction of the Vera C. Rubin Observatory (https://rubinobservatory.org/) in Chile has crossed a major milestone with the successful installation of the secondary mirror assembly. The 3.5 meter convex mirror is the first permanent optical component to be integrated into the Simonyi Survey Telescope. Construction is expected to be completed by 2025, when it will achieve first light. In its completed state, it will effectively be the largest digital camera in the world, built to perform the Legacy Survey of Space and Time (LSST), a project to create a ten-year time-lapse view of the entire southern sky.

The mirror is made from Corning® ULE® Glass (Ultra-Low Expansion Glass), and was manufactured by Corning Advanced Optics in Canton, New York. After delivery in 2009, it was stored at Harvard University for five years. After this, L3Harris Technologies, in Rochester, New York, got to work finishing and polishing the mirror. They developed new techniques to work the mirror, as it is very technically challenging to work such a large convex mirror to the necessary precise tolerance. They also designed and built the mirror’s cell assembly, which has adaptive optics capabilities. The cell is built on a stiff steel mounting plate and features 72 axial actuators and six tangent actuators. These allow the supporting structure to constantly adjust as the telescope moves, compensating for the distorting effect of its own weight to keep the mirror at exactly the correct shape at all times.

In 2018, the mirror and cell assembly were shipped to the observatory site in Chile. On arrival, it was given its silver coating. Telescope mirrors are usually coated with aluminum, which is hardier and less prone to tarnishing, and so doesn’t need to be renewed as often. But the Simonyi Survey Telescope in the Vera C. Rubin observatory uses silver (for its superior reflectivity) together with a protective coating to seal it away from atmospheric oxygen and extend the life of the coating. After silvering, it was then sealed back into its container to be stored until construction had reached the point where the telescope would be ready for it. Finally, in July 2024, the complete assembly was installed into the telescope, and integrated with its control electronics.

“Working with the mirror again after five years is extremely exciting because it really feels like we’re in the home stretch,” said Sandrine Thomas, Deputy Director for Rubin Observatory Construction, “Now we have glass on the telescope, which brings us a thrilling step closer to revolutionary science with Rubin.”

The mirrors in observatory telescopes need to be removable, so that they can be cleaned and occasionally resurfaced. But these large mirrors are very heavy, and it would be a disaster if so much glass were to be dropped. That’s why installation and removal is done very carefully, with specialized machinery, following a documented process. To install the secondary mirror assembly, engineers in the summit team loaded it onto a custom-built cart, which rotated the mirror to a vertical position. It was then hoisted up into position on the telescope structure, and carefully bolted into place. Once it was securely attached, the electronics were connected, and the software control system was activated.

“Our 55-year legacy of designing and constructing high-end optical systems for space and ground continues with the world’s largest active secondary mirror system built for Rubin Observatory,” said Charles Clarkson, Vice President and General Manager, Imaging Systems, Space and Airborne Systems at L3Harris. “With this milestone, we are closer to pushing scientific frontiers and charting the Universe like never before, and we look forward to the science that will be discovered.”

The next component to be installed will be the Commissioning Camera (ComCam). This is a temporary camera, meant to be used for testing and integration. At “only” 144 megapixels, it’s only a fraction of the size of the LSST camera. This is not the first time that ComCam has been installed – it is used at various stages of construction to test the various components, ensure that they are properly installed, and that they work together as expected. After ComCam has done its job, the team will get to work on integrating the 8.4 meter primary mirror assembly, followed by the LSST camera.

The Vera C Rubin Observatory was named after the astronomer who first provided convincing evidence of Dark Matter. She and a colleague studied over 60 galaxies to measure how fast they were rotating. In 1978, they found that these galaxies were all spinning too fast: Given the amount of visible matter, they should have not had enough gravity to stop themselves from flying apart. There had to be extra invisible mass, and this work was the first convincing proof of the Dark Matter theory.

The telescope itself is a survey instrument: It is designed to take deep, wide-field images of the sky, very rapidly. The design of the telescope allows it to move very quickly, switching from target to target in short order. With an 8.4 meter primary mirror, it is very sensitive, and can see very faint, distant objects. But it also has a very fast focal ratio of f/1.234, giving it a very wide field of view and allowing it to take much faster exposures.

When the LSST camera is installed, it will capture images covering an area of 9.6 square degrees. Each image will be made from two 15 second exposures, at a resolution of 3.2 gigapixels. At this rate, it will be able to image the entire sky every ten days, and it will repeat this process for ten years. The resulting data will be a ten year time-lapse video of the entire universe, monitoring 20 billion galaxies, 17 billion individually resolved stars, and the orbits of around 6 million objects within our Solar System!

For more information, read the original press release at https://noirlab.edu/public/news/noirlab2419/

The post Rubin's Secondary Mirror is Installed appeared first on Universe Today.

I've long been writing about "alternative cancer clinics" (i.e., quack clinics) that sell false hope in the form of very expensive but ineffective treatments to desperate cancer patients. A recent study demonstrates how they use Google to do this.

The post How Google listings are used by alternative cancer clinics to lure in desperate patients first appeared on Science-Based Medicine.

Researchers have uncovered a more nuanced view of what makes an 'ideal' computer science student, challenging long-held stereotypes of geeky, clever, detail-oriented men, who lack social skills.

Researchers have created Mindful Scroll, a mobile app that helps users transition from doom-scrolling to adding mindfulness into their daily routines.

The movement of radiant heat -- felt when a hot surface warms our bodies and homes -- between buildings and their surroundings at ground level makes buildings with less skyward-facing surfaces harder to cool. A research team has demonstrated a new passive cooling technology that coats walls and windows with materials that can better manage heat movement between buildings and their surroundings at ground level. Findings could reduce the reliance on air conditioning and provide a more environmentally friendly, low-cost and scalable option for low-income communities with limited or no access to cooling and heating systems.

“Today’s science fiction is tomorrow’s science fact.” This quote, attributed to Isaac Asimov, captures science’s intricate relationship with science fiction. And it is hardly a one-way relationship. Whereas science fiction is constantly evolving to reflect new scientific discoveries and theories, science itself has a long history of drawing inspiration from the works of visionary authors, filmmakers, and popular culture. And in some cases, where scientists themselves were the visionaries (like Asimov himself), you had an instance of both!

The relationship between the two was the subject of a recent study by Samuel Boissier, a researcher with the Centre National de la Recherche Scientifique (CNRS) and the director of research at the Laboratoire d’astrophysique de Marseille (LAM). In an age when misinformation, “deepfakes,” and deliberate attempts to obscure scientific truths are at an all-time high, examining the interconnection between science, art, and science fiction is very important. According to Boissier, doing so offers people in the scientific community a way to engage with the public in a way that is relatable and accessible.

The relationship between science fiction and scientific fact is well-documented and has been the subject of academic research. Recent examples (that we have written about) include how exoplanets are depicted, the lives of many professional scientists, and popular depictions of space travel. However, when a concept fails to meet the burden of proof – such as FTL travel using wormholes or the EMDrive – the typical reaction is to label it as “science fiction.” Nevertheless, science fiction authors are often professional scientists themselves or represent science accurately in their stories – hence the term “hard SF.”

This artist’s illustration shows a spacecraft using an Alcubierre Warp Drive to warp space and ‘travel’ faster than light. Image Credit: NASA Inspiring SF (and Vice Versa)

In his paper, Boissier (himself a professional astronomer and astrophysicist) addresses how hard science fiction can be used for educational purposes, particularly in astronomy and astrophysics! What’s more, examples can be found in many forms of popular media, including literature, film, and video games. As he told Universe Today via email:

“Science Fiction is using astronomy to offer to the public blockbusters at the movies (e.g. Interstellar), series or movies in streaming media (Don’t Look Up, The Expanse), many books from classic authors (Isaac Asimov, Arthur C. Clarke) or more moderns ones (Kim Stanley Robinson), comics (the adventures of Valerian and Laureline), or video games (Mass Effect, No Man’s Sky) that have a very large cumulated audience. Astronomers can use Science Fiction to illustrate physics or astronomical facts. It might be a good way to talk about our work and our methods by comparing them to examples with which a large audience is familiar.”

Not only do the following examples contain “hard” science, but they also explore concepts that individuals may not otherwise be familiar with. For instance, the Mass Effect series contains one of the more well-known proposed resolutions to Fermi’s Paradox, the Berserker Hypothesis (or “Killer Probe Scenario”). The Expanse series (the novels and the miniseries adaptation) is renowned for featuring scientific elements that make the story compelling and realistic. Examples include realistic depictions of life on Mars, larger asteroids, and spacecraft, including the effects of low gravity (and microgravity).

In terms of literature, Asimov and Clarke are well-known examples of scientists who used the genre to explore speculative ideas grounded in science. Asimov’s I, Robot series explored how the development of artificial intelligence (AI) would affect our society. Interestingly enough, Asimov wrote the series to address what he felt was the tired and cliched trope of robot uprisings (“kill all humans” and such!). Strangely, the novel was adapted into the 2004 film starring Will Smith, which centered on the premise of a robot uprising (what bitter irony!)

Clarke’s work earned him the nickname “the prophet of the future,” a well-deserved moniker! In Islands in the Sky (1952), he presented the concept of a Space Elevator (named Port Goddard and located in New Guinea) that allows for regular trips to space. Rendezvous with Rama presents readers with the concept of an O’Neill Cylinder traveling between star systems and presents a detailed concept of extraterrestrials. But his most well-known work is arguably 2001: A Space Odyssey, the novel released concurrently with the film in 1968.

The film itself was based on two of Clarke’s short stories, Encounter in the Dawn (1953) and The Sentinel (1948), which were adapted to create the first two parts of the film (The Dawn of Man and Mission to the Moon). These short stories explore the ideas of first contact between ancient humans and extraterrestrials (paleocontact) and the discovery of an alien artifact on the Moon. This became the basis for The Monolith in the film, which is responsible for influencing the evolution of early hominids. These ideas inspired more recent films like Prometheus, Arrivals, and others that explore paleocontact and first contact.

As Boissier explained, these novels and films inspired many to get into astronomy, astrophysics, and STEM. “In a recent study, it was shown that 93 percent of British professional astronomers have an interest in Science Fiction, and 69 percent consider that Science Fiction influenced their career or life choice. I am presenting a similar study made for French astronomers, performed during and just after the 2024 meeting of the French Society of Astronomy and Astrophysics (Journees 2024 de la SF2A).”

But, of course, the relationship between SF and popular media is hardly one-way. After the 2024 SF2A meeting, Boissier met with his colleague, astronomer Frank Selsis, who shared a few examples of how science fiction inspired scientific research. “Selsis told me after the meeting that author Laurence Suhner wrote a short story about an [exoplanet around] TRAPPIST-1 at the same time of its discovery, the observations being announced in the journal Nature at the time.”

Selsis, the research director of the Exoplanets, CLImates, and Planetary Systems Evolution (ECLIPSE) lab at the University of Bordeaux, was part of the consortium that revealed the presence of a potentially habitable exoplanet around Proxima Centauri (Proxima b) in August 2016. As he related to Boissier, he was also a co-author of a study inspired by a conversation with Luvan, a French SF author known for her novel Agrapha. During a presentation last year at the Teich Bird Sanctuary, Selsis spoke on the subject of the relationship between science fiction and exoplanet research (see video above).

Advising SF Writers

As noted, Boissier addresses how science fiction materials can be used as a pedagogical resource. Contrary to what many believe, there are many popular science fiction franchises where professional scientists advised the writers and visual effects departments. “Maybe one of the most famous examples is the imagery of the black hole and its accretion disk [in Interstellar], for which actual computations were performed,” said Boissier. “Kip Thorne was the advisor for the movie. You will find many discussions about it, including a book by Thorne himself.”

Kip Thorne’s computational models (and Interstellar‘s visuals) were confirmed in 2019 when the Event Horizon Telescope (EHT) collaboration released the first image of a supermassive black hole and its accretion disk. In 2021, the EHT released the first image of the SMBHs at the center of the Centaurus A galaxy and the radio jet emanating from it. In 2022, they revealed the first image of Sagittarius A*, the SMBH at the heart of the Milky Way galaxy! Another example that Boissier enjoys citing is the TV series Futurama, where astronomer David Schiminovich of Columbia University helped advise one of the show’s creators.

According to Boissier, this included the 2009 video Into the Wild Green Yonder, which featured a “violet dwarf star.” This was a clear reference to the work Schiminovich did with NASA’s Galaxy Evolution Explorer (GALEX) mission, which observed the Universe between 2003 and 2013 in the ultraviolet wavelength. Also, fans of the series will recall episodes that featured noted scientists like Stephen Hawking, Bill Nye, and noted environmentalist Al Gore. It has also explored concepts ranging from Schrodinger’s Cat, General Relativity, Lorentz Invariance, the “Grey Goo” scenario, and Simulation Theory.

Dr. Kip Thorne’s guidance allowed Nolan to raise science fiction to a new level in the film Interstellar. Credit: Paramount Pictures/Warner Bros. Educating with SF

In addition to recognizing how SF has inspired real-life scientists (and vice versa), Boissier also explores how SF can be used as a pedagogical resource. One of the greatest virtues, says Boissier, is the way SF can make real science accessible to people who might otherwise be intimidated to learn about it:

“I think some people are not confident enough to think they can follow an astronomy lecture or conference, [whereas] they have no problem going to the theatre to watch a Science Fiction movie. If an astronomer is there to say a few words about science after the movie, we can meet with an audience that we would not find in other places. So, to me, it is important to reach more people.”

“I have seen a presentation by Roland Lehoucq in France that was giving shining examples indeed. For instance, using the Star Wars scene in which lightning flashes from the Emperor’s fingers, he showed it is possible to compute the potential difference needed for this effect and how thick the soles of his shoes need to be to avoid electrocution. And he computed how much energy is needed for lightsabers to cut through a metal door (it’s a lot!). Many books explore these types of things, usually starting with “The Science of TITLE HERE”!

Examples include Kip Thorne’s The Science of Interstellar, Kevin R. Grazier’s The Science of Dune, and Lawrence M. Krauss and Stephen Hawking’s The Physics of Star Trek. Moreover, using SF to educate people about science is also a way of combatting misinformation, which is especially important in the “age of the internet,” where fringe theories have become more mainstream. One need look no further than social media platforms to find examples, such as “Flat Earth” theory, Creationism, and conspiracy theories involving vaccinations, election outcomes, and assorted ideas that exploit ignorance and fear.

Scientists at Cornell University have developed a “stillsuit” for NASA spacesuits that could enable longer-duration missions on the Moon and Mars. Credit: DALL-E generated image

To Boissier, this makes educating people about science, astronomy, and the STEMs (and in a way that is accessible) more important than ever. “To me, it is important because too many people are disconnected from science,” he said. “There is a lot of fake news and misinformation, including subjects on which science can help citizens understand the world. Those are opportunities to bring a little bit of science, to talk about the scientific methods that everybody should know about!”

For more information on how SF has inspired science and scientists, check out this list from the Astronomy and Astrophysics Group at the University of Warwick.

Further Reading: arXiv

The post New Study Examines the Links Between Science Fiction and Astronomy appeared first on Universe Today.

Tonight, if the sky is clear and dark in your vicinity, would be a good night for staying up late, going outside, and looking up. Not that it’s an exceptional night for star gazing, necessarily; I wrote “sky-gazing” for a reason. The two phenomena you’re most likely to see are much, much closer than the stars. Both occur in the Earth’s upper atmosphere, and are generated by effects that occur within the solar system (i.e., the Sun, its planets, and their neighborhood.)

The phenomena in question? Meteors, for sure; and auroras, just maybe.

Tonight you will definitely see an unusually large number of meteors (a.k.a. “shooting ‘stars’ “) from the annual Perseid meteor shower. Ordinary meteors are dust-grains and pebbles flying through the solar system that happen to hit the Earth. When these objects enter the Earth’s atmosphere at high speed, they heat up and glow brightly, leaving a track across the sky until they evaporate away entirely. The dust and small rocks are debris from comets, themselves balls of rock, dirt and ice, typically a few miles (kilometers) across, that orbit the Sun on trajectories that are far more elongated than the Earth’s near-circular path. You’ll see more meteors after midnight, but before midnight, the ones you see will often show long trails. However, the moon will drown some of them out before it sets, roughly one hour before midnight; try to go out after moonset if you can. (Meteors will continue to be common for an additional two or three nights, though the number will tend to decrease over time.)

You might also see auroras (a.k.a. the “northern” or “southern ” lights); there’s a moderate chance of them tonight, the more so the higher your latitude. Auroras arise when solar storms create clouds of subatomic particles that cross from the Sun to the Earth. Some of these electrically-charged subatomic particles are steered by the Earth’s magnetic field toward the Earth’s magnetic poles, and when the particles enter the atmosphere, they strike atoms, causing the atoms to glow. The colors seen most often green or red. Last week I wrote about how you can try to guess when they may be occurring. The moon, again, will drown out the colors, so look after moonset, an hour before midnight in most places.

This is not to dismiss actual star gazing. We’re still waiting for stellar event that should be visible to the naked eye: a minor star explosion known as a nova that has been predicted, with moderate confidence, to occur in the next month or so. (But… don’t be too terribly surprised if it is delayed, or doesn’t occur at all. The prediction is empirical and based only on three previous occurrences — and nature doesn’t always follow simple patterns.) I’ve written about this event here.

Again, just to reemphasize: for all of these, you need dark skies! You will barely see anything (except the brightest meteors) from a city, or even from a suburb with parking-lot lights nearby. Get as far from lights as you can — stay away from busy roads where headlights will periodically blind you — and let your eyes adjust to the darkness.

Now here’s something worth contemplating.

• Meteors and auroras typically occur 50-200 miles (100-300 km) overhead — no further than the distance from Boston to New York or from London to Paris.
• The nova explosion, if it occurs, will be more than 10,000,000,000,000,000 miles (km) overhead — a hundred million times further than the Sun is from Earth.

But they’re comparably bright. Just to keep things in perspective.

I highly recommend that you click on the photos to enlarge them.

On Friday we set out to go to the drier part of the Cape Floristic Region, heading from the lusher fynbos to the karoo, a semi-desert which nevertheless harbors a lot of endemic plants and birds.

But the night before we had a big dinner, whipped up by Rita, the night before. It featured lamb chops, sausages, pap (African cornmeal mush) with tomato sauce, salad, garlic bread, and of course the local Shiraz. As you see, we were not gastronomically deprived.

My plate:

Of course there was the wine of the property: a creditable chenin blanc (I’m amazed they can make wine there at all, much less good wine):

At stops along the way to the karoo, we saw several stuffed specimens of local wildlife, which is sad but I’m sure they were shot a while back before trophy hunting became somewhat taboo.

This is a Verreaux’s eagle (Aquila verreauxii), which has a distinction of extreme prey specificity. According to Wikipedia,

Verreaux’s eagle is one of the most specialized species of accipitrid in the world, with its distribution and life history revolving around its favorite prey species, the rock hyraxes. When hyrax populations decline, the species have been shown to survive with mixed success on other prey, such as small antelopes, gamebirds, hares, monkeys and other assorted vertebrates.

The Cape leopard is a subspecies of the African leopard (Panthera pardus pardus), and there’s only one species in toto. Cape leopards are smaller than those further north (the “normal” leopard), perhaps because prey are sparser and so they evolved to do with less food, which means a smaller body.  Some miscreant shot this one, whose stuffed remains we found in a snack bar/restaurant/shop.

It poured the night we left the lovely Driehoek Farm, and we checked in with the managers, who informed us that the rivers were running high and swift, damaging bridges, turning rivulets into dangerous torrents, and even overturning a car (the occupants survived). Martim carefully got maps of all the rivers, which we hoped would have gone down when we crossed what were identified to us as the Three Major Obstacles. Fortunately, we made them all, though the last (where the car overturned) was the diciest.

Obstacle #1–no problem!

Some flowers we saw heading towards the karoo. This one is unidentified, but may be Helichrysum.

Metalasis sp. (African blombos)

Another unknown flower from the daisy family

A must-see in this part of the karoo are the San people’s (previously called “Bushmen”) rock paintings in the Truitjieskrall Reserve of the Cederberg Mountains (see also here).  Although there are fewer paintings than at some other sites, it was accessible with the purchase of a permit (it gives you the code for the lock), and the surrounding rocks, in whose caves and crevices the San clearly sheltered, are fantastic. Below is the rock complex:

. . . and some of the rocks:

You can se that there are many places to shelter here, and although the San apparently didn’t wear anything above the waist (a mystery to me given the cold), they also had fires and plenty of caves and overhangs:

This is the site where all the paintings are; they are exposed to the elements and, sadly, will eventually disappear. Most of the faces of the human figures, depicted in white instead of the usual red ochre pigments, are already gone.

The entrance to the cave, on whose walls the San did their art, is to the right. I can’t say how old these paintings are as it’s been very hard to date them. The oldest in South Africa appear to be 8,000 years old, and the youngest, depicting ships and wagons of the Europeans, are from the 19th century.

This plaque (click to enlarge) tells how they made and used pigments. Painting was sophisticated, often using fine brushes rather than fingers and hands. Curiously, the later paintings appear to be less fine, made without brushes.

The inside of the cave.  You can see one painting in red at the lower right:

This is identified on another plaque as showing “five women clapping and dancing. The men on either side are postures typical of trance healers. The dances were held regularly to allow trained healers to receive power from the spirit world to heal the sick and help the community.”

I presume this is known from observations of San hunter-gatherers (a few still exist) in modern times.

“A line of six female eland. In the San belief system, eland could help people get close to the spirit world where they could access power for healing and making rain.  Many paintings depict spiritual experiences and show associated animals.”

Clearly a man! But his face, originally painted in white, has disappeared as the white pigments didn’t bond as tightly to the rock as did the white ones

More figures and an unknown animal to the right. San paintings in other places showed elephants, but I doubt that the San could bring them down with their spears, though perhaps they killed young ones.

A line of dots; I don’t know what they represent:

An enlargement of the three figures above holding hands.

More of the gorgeous rock formations:

The cylindrical rock must be simply part of the formation:

Obstacle #3!  This is where a car had overturned the night before. When we arrived before lunch it had been removed, but yet another car had been swept off the road into the rushing water. In the picture below this one, a group of people are about to tow the car out of the water. I don’t know if they succeeded.

The Obstacle. After observing several cars go through the stream, Martim, an intrepid driver, essayed the obstacle and we made it!

We celebrated with ribs for lunch, as a woman at the shop where we stopped said her friend made some wicked ribs there. Well, I’m a BBQ maven, and all I can say is that they were just okay. But with some fries and a beer they hit the spot.

This menu shows South African humor as well as their tremendous love of MEAT, something I didn’t know before I came here. (A local joke is that in South Africa, chicken counts as a vegetable.) Just read the part by the asterisk.

More attempts at humor on another menu board:

Oranges are grown in the karoo, making for a strange sight:

This is melkbos (“milk bush”, Euphorbia burmanii), which exudes a viscous and somewhat poisonous sap when you break the stems (see next photo):

Martim said that the San dipped their spear points and arrowheads into the semi-toxic sap to help bring down the animals.

Our next stop was another Afrikaaner farm that doubled as a motel, one with a clear Wild West theme. One room was called “the Jailhouse,” another “sheriff’s office”, while I had the House With No Name (in the desert, they can’t remember the names!).  I called it, in keeping with the theme, “The Bordello.”  In the dining room (here they feed you) there were displays of saddles, Western cowboy hats, and rifles.  The farm offers horseback riding.

The inside of my room, which has a boiler called a “donkey” that you have to turn on by lighting a fire under it. None of us wanted to do that, even though it was bloody cold. And I mean COLD!  It took me an hour to warm up sufficiently to even think about sleeping, even though I was under a comforter and a thick blanket.

But I had an Afrikaans Bible in my room. The faithful insinuate themselves everywhere, even in the frigid karoo!

The best part of this farm was the home-cooked meals. This is dinner for five people (Martim, Rita, their two daughters, and me), and it’s enough food for at least 15 people (we also had beer and soda). Lamb slices, mutton stew, two quiches, potatoes mixed with eggs, vegetables, vegetarian lasagne, and gravy.

Martim is an inveterate hiker, so he got up at 7 a.m. and walked around the property. He found a hole just dug by an aardvark (Orycteropus afer) as a burrow. (“Aardvark” means “earth pig” in Afrikaans.). Aardvarks are shy and are hard to see, but can dig at the rate of one meter every five minutes. Their evening burrows are from 1-6 meters long.

A footprint nearby, almost surely of the aardvark.

A succulent plant (probably from the iceplant family, Aizoaceae) from the dry areas. Lots of people uproot succulents to take them home for decoration. Not good for the environment.

A view of the karoo:

Martim, PCC(E) and Rita in the karoo, photo by one of their daughters.

On the way back to Capetown, we saw several signs saying “Watch for baboons” or “Be careful of baboons”.  The chacma baboon (Papio ursinus) can be either dangerous, boisterous, ravenous, or all three. You don’t want to be around one of these (I took the photo as we passed them in the car) if it’s had experience with human food. In some places they have even learned the noise that a beeper makes when you use it to open a car door, and have learned to rush to the car and open the door (and get inside) when they hear that noise, hoping to ransack the car for food. Martim was once knocked down by a boisterous chacma that jumped on his back.

. . . and the fulfillment of a culinary dream. Ever since I heard of bunny chow, an Indian-inspired workingman’s food in South Africa, I’ve wanted to try one. Yesterday Martim and Rita, while visiting a friend, happened upon a good place to get bunny chow, and phoned me. I asked for a “quarter bunny,” which you’ll see below. From Wikipedia:

Bunny chow, often referred to simply as a bunny, is an Indian South African fast food dish consisting of a hollowed-out loaf of white bread filled with curry and a serving of salad on the side. It originated among Indian South Africans of Durban. Throughout various South African communities, one can find cultural adaptations to the original version of the bunny chow, which uses only a quarter loaf of bread and is sometimes called a skhambane, kota (“quarter”) or shibobo, a name it shares with sphatlho, a South African dish that evolved from the bunny chow.

. . . The traditional Indian meal was roti and beans, but the roti tended to fall apart as a take-away item. To solve this, the centre portion of a loaf of white bread was hollowed out and filled with curry, then the filling was capped with the portion that was carved out.

. . . Bunny chow was created in Durban, South Africa, which is home to a large community of people of Indian origin.

Here’s a quarter bunny with lamb curry. It was terrific, and you can eat it with your hands, as is the custom, sopping up the curry with the bread removed when the quarter loaf is hollowed out to make a bread bowl (you can also get a half bunny).

Sure good eating, I gar-un-tee! (Photos by Martim.)

p.s. From the balcony of the house, we saw a whale disporting itself in the waters of the bay. This was just a few minutes ago (I’m writing at 8 a.m. South African time on Sunday.)

Meanwhile, in Dobrzyn, Hili has her eyes on the future – or the past:

Hili: I’m dreaming about spring. A: It’s summer now. Hili: So what?

Hili: Marzy mi się wiosna.
Ja: Teraz jest lato.
Hili: I co z tego?

Astronomers have confirmed the existence of exoplanets with extremely small orbits around their stars. But what about exoplanets that get close enough to be devoured by their star, and what if it’s an Earth-sized exoplanet? This is what a recent study accepted to AAS Journals hopes to address as an international team of more than 50 researchers investigated an Earth-sized exoplanet with an orbital period of only 5.7 hours, known as “ultra-short-period” (USP) exoplanets, that could eventually experience what’s known as tidal disruption, resulting in its devourment by its star. This study holds the potential to help researchers better understand the processes responsible for this, along with continuing to challenge our understanding of exoplanetary architectures, as well.

Here, Universe Today discusses this amazing research with Dr. Fei Dai, who is an Assistant Astronomer in the Institute for Astronomy at the University of Hawai’i and lead author of the study, regarding the motivation behind the study, significant results, potential follow-up studies, the significance of this exoplanet being Earth-sized, and whether this could occur in our own solar system. Therefore, what was the motivation behind this study?

“Tidal disruption could be a potential fate of rocky planets,” Dr. Dai tells Universe Today, as he notes a March 2024 study published in Nature that he was a co-author of and discusses tidal disruption, which was such a profound study that it was featured on the journal’s cover. “It seems like about 10 percent of sun-like stars might have engulfed their rocky planets. This system TOI-6255 is the best-known progenitor for those planet engulfment events. The tidal disruption of rocky planets allows us to probe their interior composition and compare with Earth.”

For the study, the researchers analyzed TOI-6255 b, whose radius is ~1.08 and mass is ~1.44 of Earth’s and located just over 20.4 parsecs (65.2 light-years) from Earth. However, while being Earth-sized holds promise for life, TOI-6255 b’s 5.7-hour orbit not only make this exoplanet far too hot for life as we know it to exist, but this also means its orbit takes it dangerously close to what’s known as Roche limit. This is the distance a smaller object can orbit a larger object until the larger object’s gravity tears the smaller object to pieces, along with TOI-6255 b also experiencing the aforementioned tidal disruption, which is a common occurrence throughout the cosmos, including black holes. Therefore, what were the most significant results from the study?

Dr. Dai tells Universe Today, “This planet is doomed for tidal disruption in 400Myr which is short on cosmic scale (~13Gyr). The planet is also tidally distorted to be football like in shape (10 percent deviation from sphere), in comparison Earth’s tidal distortion due to the moon is only 1e-7 [0.0000001] level.”

Regarding potential follow-up studies the researchers note they aspire to accomplish with NASA’s James Webb Space Telescope, Dr. Dai tells Universe Today, “Orbital phase curve study of this planet could confirm that it is indeed tidally distorted. We know what the phase curve should look like for a spherical planet, tidally distorted planet has a strong deviation from that. We can also see if the surface of the planet is covered by lava pool as would be expected on a planet this hot.”

USPs are exoplanets whose orbits are less than one day and whose masses are less than 2x the Earth. While intriguing, only about 100 USPs have been discovered with a 2014 study estimating approximately 0.5 percent exist around Sun-like stars and a 2019 study discussing their bulk composition (i.e., mass of its iron core and mantle). As noted, given their extremely short orbit, these worlds are likely too hot for life as we know it to exist, and along with USPs are the familiar “hot Jupiters” who orbit their stars in only a few days and astronomers estimate their population is in the hundreds. As their name literally implies, these worlds are Jupiter-sized or larger gas planets and are also potentially far too hot for life as we know it to exist. But what is the significance of TOI-6255 b being an Earth-sized planet as opposed to a Jupiter-sized planet, or larger?

Dr. Dai tells Universe Today, “Planets similar to Earth in size are most likely rocky i.e. mostly made of iron core and silicate mantle. They show us what terrestrial planets in other planetary systems are made of. Jupiter-sized planets are most certainly covered by thick hydrogen and helium atmospheres. Jupiter-sized planets are unlikely to harbor life.”

While TOI-6255 b isn’t due for disassembly for another 400 million years, watching any exoplanet get ripped to shreds by its host star could provide important insights regarding the planet’s exterior and interior compositions, thus helping us better understand the similarities between exoplanets and planets within our own solar system. These unique worlds and their extremely tight orbits have challenged our understanding of solar system architecture throughout our Milky Way Galaxy, as Mercury is the closest planet to our Sun, and it still takes 88 days to complete one orbit.

For now, one similarity between our solar system and exoplanetary systems is the Roche limit. However, the study also focuses on tidal disruption that is physically distorting TOI-6255 b, with Dr. Dai mentioning above that “Tidal disruption could be a potential fate of rocky planets”. Therefore, what are the chances of tidal disruption occurring for rocky planets in our solar system, and why?

Dr Dai tells Universe Today, “Tidal disruption of planets is minimal in our solar system. However, the rings of Saturn are thought to originate from tidal disruption of satellites around Saturn. Tidal forces are strongly dependent on orbital separation, only objects with the shortest orbital period experience significant tides.”

What new discoveries about tidal disruption on Earth-sized worlds will astronomers make in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Good Thing We Found this Earth-Sized Planet Now. It’s About to Be Destroyed appeared first on Universe Today.

In 1974, astronomers Bruce Balick and Robert L. Brown discovered a powerful radio source at the center of the Milky Way galaxy. The source, Sagittarius A*, was subsequently revealed to be a supermassive black hole (SMBH) with a mass of over 4 million Suns. Since then, astronomers have determined that SMBHs reside at the center of all galaxies with highly active central regions known as active galactic nuclei (AGNs) or “quasars.” Despite all we’ve learned, the origin of these massive black holes remains one of the biggest mysteries in astronomy.

The most popular theories are that they may have formed when the Universe was still very young or have grown over time by consuming the matter around them (accretion) and through mergers with other black holes. In recent years, research has shown that when mergers between such massive objects occur, Gravitational Waves (GWs) are released. In a recent study, an international team of astrophysicists proposed a novel method for detecting pairs of SMBHs: analyzing gravitational waves generated by binaries of nearby small stellar black holes.

The study was led by Jakob Stegmann, a Research Fellow at the Max Planck Institute for Astrophysics (MPA) and the Gravity Exploration Institute at Cardiff University. He was joined by researchers from the Niels Bohr Institute, the Center for Theoretical Astrophysics and Cosmology at the University of Zurich (CTAC-UTZ), and the California Institute of Technology (Caltech). The study that describes the team’s findings, “Imprints of massive black-hole binaries on neighboring decihertz gravitational-wave sources,” recently appeared in Nature Astronomy.

First detected in 2015 by scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO), Gravitational Waves (GWs) are ripples in spacetime caused by the merger of massive objects like white dwarf stars and black holes. While multiple signals involving binary pairs of merging black holes have been detected, no GW events involving SMBHs have been detected because current Earth-based detectors are not sensitive to the very low frequency these events emit. Much like the issues facing ground-based observatories, scientists hope to remedy the situation by developing space-based instruments.

This includes the proposed Laser Interferometer Space Antenna (LISA), an ESA-led mission that is expected to launch sometime in 2035. Unfortunately, detecting mergers between the largest black holes in the Universe will still be impossible. However, Stegmann and his colleagues propose that binary SMBHs can be detected by analyzing the gravitational waves generated by smaller black hole binaries. Their proposed method leverages the subtle changes SMBHs cause to the GWs emitted by a pair of nearby smaller black holes.

In this respect, small black hole binaries work as a beacon, revealing the existence of larger pairs of merging black holes. As Stegmann explained in a recent UHZ press release:

“Our idea basically works like listening to a radio channel. We propose to use the signal from pairs of small black holes similar to how radio waves carry the signal. The supermassive black holes are the music that is encoded in the frequency modulation (FM) of the detected signal. The novel aspect of this idea is to utilize high frequencies that are easy to detect to probe lower frequencies that we are not sensitive to yet.”

Artist’s impression of the Laser Interferometer Space Antenna (LISA). Credit: ESA

However, the evidence that this proposed method offers would be indirect, coming from the background noise collectively generated by many distant binaries. Furthermore, it will require a deci-Hz gravitational-wave detector, which is far more sensitive than current instruments. For comparison, the LIGO detector measures GWs in the 7.0 kHz to 30 Hz range, whereas the Virgo Observatory can detect waves in the 10 Hz to 10000Hz range. By detecting the tiny modulations in signals from small black hole binaries, scientists could identify merging SMBHs ranging from 10 to 100 million Solar masses, even at vast distances.

As Lucio Mayer, a black hole theorist at the University of Zurich and a co-author of the study, added:

“As the path for the Laser Interferometer Space Antenna (LISA) is now set, after adoption by ESA last January, the community needs to evaluate the best strategy for the following generation of gravitational wave detectors, in particular which frequency range they should target – studies like this bring a strong motivation to prioritize a deci-Hz detector design.”

Further Reading: UZH, Nature Astronomy

The post Scientists Develop a Novel Method for Detecting Supermassive Black Holes: Use Smaller Black Holes! appeared first on Universe Today.