Michael J. Behe's Blog, page 60

How Could Life Evolve From Cyanide?

How did life arise on Earth? Steven Strogatz speaks with the Nobel Prize-winning biologist Jack Szostak and Betül Kaçar, a paleogeneticist and astrobiologist, to explore our best understanding of how we all got here.

How did life begin on Earth? It’s one of the greatest and most ancient mysteries in all of science — and the clues to solving it are all around us. Biologists have sometimes imagined evolutionary history as a recorded “tape of life” that might turn out differently if it were replayed again and again. In this episode, Steven Strogatz speaks with two researchers inspecting different parts of the tape. First, hear from the Nobel Prize-winning biologist Jack Szostak, who explores how a boiling pool laced with cyanide could have given rise to essential life elements like RNA and DNA. Then hear from Betül Kaçar, a paleogeneticist and astrobiologist who resurrects ancient genes to learn how they helped evolve the processes essential to modern life.

Portions of a transcript of the recorded interview follow:

 Did life begin, as Charles Darwin once speculated, in a warm little pond somewhere? The kind of nurturing, supportive place where it’s easy to picture delicate biology taking shape? Or more counterintuitively, as some scientists have proposed, did life get started deep down in the ocean, near hydrothermal vents, a seemingly inhospitable place where the pressures are enormous, and the temperatures are scalding? And, wherever life began, what were the earliest building blocks of life? Were they the molecules that we hear so much about today — RNA and DNA, amino acids, lipids — or were there something much simpler? In the past few years, some important clues have turned up. The payoff to answering these kinds of questions would be huge, not just for understanding how life began on Earth, but also to help us look for life on other planets, and maybe to figure out if we are alone in the universe.

(01:17) Joining me to discuss all this is Jack Szostak. Jack is a professor of chemistry and chemical biology at Harvard University, a professor of genetics at Harvard Medical School, and an investigator in the department of molecular biology at Mass General Hospital. He shared a Nobel Prize in 2009 for his work on the discovery of telomerase, an enzyme that protects chromosomes from degrading.

Strogatz (01:55): Let me start with a question about the origin of life. As I say, it’s one of the greatest mysteries in all of science and the attempt to solve it seems like one of the greatest detective stories of all time. What would be your best guess for how life began on Earth?

Szostak (02:09): Okay, so, so I think we have to think about some environment on the surface of the Earth, some kind of shallow lake or pond where the building blocks of RNA were made and accumulated, along with lipids and other molecules relevant to biology. And then they self-assembled into lipid vesicles encapsulating RNA, under conditions where the RNA could start to replicate driven by energy from the sun. And that would allow Darwinian evolution to get started. So that the, some RNA sequences that did something useful for the protocell that they’re in would confer an advantage, those protocells would start to take over the population. And then you’re off and running, and life can gradually get more complex and evolve to spread to different environments, until you end up with what we see around us today.

Let me just stop the tape here for a moment. Even a Nobel Prize winning biologist, who we might think cares deeply about how nature actually works, uses phraseology in his “best guess for how life began on Earth” that carelessly ignores stupendous difficulties that completely undermine the abiogenesis hypothesis. He spins off these statements like overripe political campaign promises:

“blocks of RNA were made and accumulated, along with lipids and other molecules relevant to biology”
“And then they self-assembled into lipid vesicles encapsulating RNA, under conditions where the RNA could start to replicate driven by energy from the sun.”
“And that would allow Darwinian evolution to get started.”
“And then you’re off and running, and life can gradually get more complex and evolve to spread to different environments, until you end up with what we see around us today.”

Szostak (05:12): For decades, thinking about the origin of life was confused, because everything in modern life depends on everything else. So it’s, so you have the DNA encoding the sequence of RNA and proteins, but you need the proteins to replicate the DNA. And to transcribe DNA into RNA, you need RNA to make protein. So you need — all parts of the system need all the other parts. So it was kind of a logical conundrum. And the answer, the solution to that, came with the so-called RNA world idea, which was originally postulated by some very smart people, like Francis Crick, and Leslie Orgel in the late ’60s, with the idea that RNA maybe had the ability to act as an enzyme.

Szostak (06:40): Okay, so tRNA is short for transfer RNA. It’s a relatively short set of RNA molecules, around 70 or 80 nucleotides long, and they carry amino acids to the ribosome. And then the catalytic machinery of the ribosome takes the amino acids from the tRNA, and assembles them into a growing peptide chain. So there’s a lot of roles for RNA in making proteins. There’s the tRNA that brings in the amino acids, there’s the RNA components of the ribosome, that it turns out actually orchestrate everything, do the catalysis. And of course, there’s the messenger RNA, which, you know, I think now everybody knows about messenger RNA these days, don’t they?

Strogatz (09:14): Well, maybe we should talk about cyanide, since you brought it up. I’m sure many people listening to this will be horrified, thinking that cyanide is how you kill people.

Szostak (09:22): I think it’s one of the lovely ironies of the whole field, that the best starting material to build all of the molecules of life, turns out to be cyanide.

Strogatz (11:54): Hm. Incredible. So, maybe we should return then to this theme of, you know, now that we’ve got cyanide world, we can somehow go up to RNA world, except that, apparently, that’s a big mystery, still, right?

Szostak (12:51): Well, I think the pathway to getting to two of the four building blocks of RNA is maybe 90% worked out? And I’d say one of the biggest steps — we have all this energy from sunlight, right? But the question is, how do you transform that energy into energy that’s in a useful form, a kind of chemical energy that can drive these building blocks to condense into long RNA chains? I think we would all agree that that has not been solved.

Let’s pause the tape again. When will origin-of-life researchers (publicly) acknowledge that living systems require specified complexity. Even if it were easy to condense the building blocks of RNA to long chains, the missing key is getting the correct sequence. Random strings of letters are easy to produce (the typing monkey business), but getting a reproduction of a meaningful essay just won’t happen by chance in the spacetime history of our universe. Nor can the result come about by a law of nature (emergent or otherwise), since the forces holding the “letters” together are not discriminatory.

Szostak (15:47): Okay, I can tell you where we are. So, several years ago, we found ways of making these primitive membranes, fatty acid membranes, grow and divide. They’re easy to feed with more fatty acids. And it doesn’t take very much to make them divide. So, for example, gentle shaking will do it. On the other hand, getting RNA sequences to replicate is a much harder problem. And so, that’s why that’s — we’re really focusing on that in my lab at the moment. We’ve been getting better at copying RNA sequences. So that means if you have, say you have one strand of RNA, you can use it as a template to build up the complementary strand, and then you’ll get a double helix, sort of like the double helix of DNA, except an RNA double helix. But a big problem then is how do you get those strands apart and copy the copies, and then copy those copies. And we have ideas about how to do it, but we haven’t gotten there yet. That’s the big challenge for the next couple of years.

Quanta

Obviously, there’s room for much interesting biochemical experimentation to be done, and we have much to learn. But let’s not pretend that nature can do what already-discovered limitations of nature say it can’t do.

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An op-ed finally makes pro-abortion values clear: Yes, abortion is “killing” and that’s okay!

Readers probably know by now that, as the Babylon Bee puts it, the U.S. Supreme Court’s war on all preborn humans was itself aborted on Friday in its 198th trimester. Pragmatic details here.

Various Hard Left types are eviscerating each other as to who’s to blame but one op-ed stood out for its refreshing clarity:

There is something infantilizing about denying the fact that embryos die when we scrape them out of the bodies of which they are a part. It sentimentalizes pregnant or potentially pregnant humans as fundamentally nonviolent creatures to imply that we can’t handle the truth about what we are up to when we opt out. And it patronizes abortion-getters to insist that we are only making a health care choice, rather than (also) extinguishing a future child. In my view, recognizing that gestating manufactures a proto-person requires acknowledging that abortion kills a proto-person. A baby is completely dependent on human care in order to stay alive, but its needs could be filled by any person—whereas a fetus, a proto-person, is ineluctably dependent on specific person…

As long as people are performing pregnancy on this earth, they must be free to change their minds about seeing it through. The adoption industry could be revolutionized and child welfare lavishly subsidized; regardless of the available supports, no one should be pregnant involuntarily. The science of medicine dictates that when foreign organisms inhabit the human body unwelcomely, we tend to eject them…

What would it mean to acknowledge that a death is involved in an abortion? Above all, it would allow for a fairer fight against the proponents of forced gestating. When “pro-life” forces agitate against feticide on the basis that it is killing, pro-abortion feminists should be able to acknowledge, without shame, that yes, of course it is. When we withdraw from gestating, we stop the life of the product of our gestational labor. And it’s a good thing we do, too, for otherwise the world would sag under the weight of forced life. It is a hard pill to swallow for a misogynist society, sentimentally attached to its ideology of patriarchal motherhood, but the truth is that gestators should get to decide which bodies to give form to. This choosing is our prerogative. A desire not to be pregnant is sufficient reason in and of itself to terminate a gestatee.

Sophie Lewis, “Abortion Involves Killing–and That’s OK!” at The Nation (June 22, 2022)

And mark the closing lines:

… Our is the mature pro-life politics. I don’t want to live in a world that valorizes life for its own sake. I want to live in a world that prioritizes the life chosen and wanted. Peoples’ lives are worth more than fetuses’ lives

Sophie Lewis, “Abortion Involves Killing–and That’s OK!” at The Nation (June 22, 2022)

This last comment chimes well with historian Yuval Noah Harari, an elite globalist darling, obsessing about what to do with all the “useless,” “meaningless,” and “worthless” people in the world.

Meanwhile, here’s a fearless independent Canadian news hack covering the pro-abortion demos in New York:

People like him are widely hated by the official Canadian media who take taxpayers’ money from the government to stay in business.

Hat tip: Matt Vespa for Sophie Lewis comments.

You may also wish to read: A Great Reset historian muses on what to do with “useless” people. Transhumanist Yuval Noah Harari, a key advisor to the World Economic Forum, thinks free will is “dangerous” and a “myth.” It’s not clear that, given his intense, dramatic focus on “useless,” “meaningless,” and “worthless” people, Harari is far off from totalitarianism.

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DEVELOPING, the US Supreme Court reverses Roe v Wade (is it cry havoc?)

Having returned from a shopping trip to Junction, Jamaica [here for 4x bereavement reasons], I noticed news as captioned. I clip:

https://www.breitbart.com/politics/2022/06/24/supreme-court-overrules-roe-v-wade-in-dobbs/

Supreme Court Overrules Roe v. Wade in Dobbs Decision – Returns Abortion to State Lawmakers

WASHINGTON, DC – The Supreme Court overruled Roe v. Wade on Friday, holding in the Dobbs case that the Constitution does not include a right to abortion and returning the issue of abortion laws and regulations to state legislatures.

Justice Samuel Alito wrote for the Supreme Court in Friday’s 5-4 [–> 6-3] decision:

>>Abortion presents a profound moral question. The Constitution does not prohibit the citizens of each State from regulating or prohibiting abortion. Roe and Casey arrogated that authority. We now overrule those decisions and return the authority to the people and their elected representatives.>>

Roe was handed down in 1973 in a 7-2 decision, holding that the U.S. Constitution includes a constitutional right to abortion, despite the fact that abortion is not found in the text, structure, or history of the Constitution, and the nation went more than 180 years without ever noticing it existed. It has been one of the most divisive legal issues in American history.

An early draft of Alito’s opinion leaked in May, the first such leak of a full opinion in the 233-year history of the Supreme Court, leading the left to violent protests, including destroying a pro-life center in Wisconsin, vandalizing churches, and threatening protests at the home of conservatives justices in violation of federal law.

These threats have culminated in what was almost an assassination attempt of Justice Brett Kavanaugh, which went seemingly unnoticed by President Joe Biden – who did not speak out to condemn it – and has led to rapid action on a new federal law to protect the justices. The court majority evidently stood firm against the threats and public pressure, overruling Roe and the later revision of Roe in 1992, Planned Parenthood v. Casey.

With Roe overruled, the issue of abortion now goes back to the states to pass whatever restrictions on abortions the voters of each state choose to adopt.

This is an issue that pivots on life, the first right, and lurking within is, what is law and what may a civil authority legitimately rule as law. DEVELOPING

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At Sci-News: Early Humans were Present in Southeast Britain 620,000 Years Ago

The archaeological site of Fordwich in northeast Kent, England, reveals the presence of Acheulean hominins — possibly Homo erectus or Homo heidelbergensis — in what is now southeast Britain between 620,000 and 560,000 years ago.

Northern Europe experienced cycles of hominin habitation and absence during the Middle Pleistocene.

Several gravel terrace sites in the east of Britain and north of France provide a majority of the data contributing to this understanding, mostly through the presence or absence of stone-tool artifacts.

To date, however, relatively few sites have been radiometrically dated, and many have not been excavated in modern times, leading to an over-reliance on selectively sampled and poorly dated assemblages of stone tools.

This includes the site of Fordwich where over 330 handaxes were discovered through industrial quarrying in the 1920s.

“The diversity of tools is fantastic. In the 1920s, the site produced some of earliest handaxes ever discovered in Britain,” said Dr. Alastair Key, director of the excavations and an archaeologist in the Department of Archaeology at the University of Cambridge.

The researchers have dated these stone tool artifacts using infrared-radiofluorescence (IR-RF) dating, a technique which determines the point at which feldspar sand-grains were last exposed to sunlight, and thereby establishing when they were buried.

“The range of stone tools, not only from the original finds, but also from our new smaller excavations suggest that hominins living in what was to become Britain, were thriving and not just surviving.”

It is thought that European populations of Homo heidelbergensis evolved into Neanderthals while a separate population of Homo heidelbergensis in Africa evolved into Homo sapiens.

A collection of footprints at Happisburgh in Norfolk dated to 840,000 or 950,000 years ago, currently represent the oldest evidence of hominins occupying Britain.

At the time, Britain was not an island but instead represented the north-western peninsular of the European continent.

Sci-News

Note that hominins have not been genetically traced as descendants of modern humans (Homo sapiens).

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Artificial photosynthesis can produce food without sunshine

Scientists are developing artificial photosynthesis to help make food production more energy-efficient here on Earth, and one day possibly on Mars.

Photosynthesis has evolved in plants for millions of years to turn water, carbon dioxide, and the energy from sunlight into plant biomass and the foods we eat. This process, however, is very inefficient, with only about 1% of the energy found in sunlight ending up in the plant. Scientists at UC Riverside and the University of Delaware have found a way to bypass the need for biological photosynthesis altogether and create food independent of sunlight by using artificial photosynthesis.

How easy would it be for biochemists to design and produce the photosynthetic mechanism from scratch, without having studied how it “has evolved in plants”?

Plants are growing in complete darkness in an acetate medium that replaces biological photosynthesis.

The research, published in Nature Food, uses a two-step electrocatalytic process to convert carbon dioxide, electricity, and water into acetate, the form of the main component of vinegar. Food-producing organisms then consume acetate in the dark to grow. Combined with solar panels to generate the electricity to power the electrocatalysis, this hybrid organic-inorganic system could increase the conversion efficiency of sunlight into food, up to 18 times more efficient for some foods.

Experiments showed that a wide range of food-producing organisms can be grown in the dark directly on the acetate-rich electrolyzer output, including green algae, yeast, and fungal mycelium that produce mushrooms. Producing algae with this technology is approximately fourfold more energy efficient than growing it photosynthetically. Yeast production is about 18-fold more energy efficient than how it is typically cultivated using sugar extracted from corn. 

“We were able to grow food-producing organisms without any contributions from biological photosynthesis. Typically, these organisms are cultivated on sugars derived from plants or inputs derived from petroleum—which is a product of biological photosynthesis that took place millions of years ago. This technology is a more efficient method of turning solar energy into food, as compared to food production that relies on biological photosynthesis,” said Elizabeth Hann, a doctoral candidate in the Jinkerson Lab and co-lead author of the study. 

“We found that a wide range of crops could take the acetate we provided and build it into the major molecular building blocks an organism needs to grow and thrive.”

“Using artificial photosynthesis approaches to produce food could be a paradigm shift for how we feed people. By increasing the efficiency of food production, less land is needed, lessening the impact agriculture has on the environment. And for agriculture in non-traditional environments, like outer space, the increased energy efficiency could help feed more crew members with less inputs,” said Jinkerson.

EurekAlert

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At Quanta Magazine: A New Physics Theory of Life

Jeremy England, a 31-year-old physicist at MIT, thinks he has found the underlying physics driving the origin and evolution of life.

Quanta editor, Natalie Wolchover, writes:

Why does life exist?

Popular hypotheses credit a primordial soup, a bolt of lightning and a colossal stroke of luck. But if a provocative new theory is correct, luck may have little to do with it. Instead, according to the physicist proposing the idea, the origin and subsequent evolution of life follow from the fundamental laws of nature and “should be as unsurprising as rocks rolling downhill.”

From the standpoint of physics, there is one essential difference between living things and inanimate clumps of carbon atoms: The former tend to be much better at capturing energy from their environment and dissipating that energy as heat. 

As a physicist, I’ll point out that an inanimate clump of carbon atoms, known as a lump of coal, is nearly ideal at capturing sunlight and dissipating that energy as heat.

 Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. The formula, based on established physics, indicates that when a group of atoms is driven by an external source of energy (like the sun or chemical fuel) and surrounded by a heat bath (like the ocean or atmosphere), it will often gradually restructure itself in order to dissipate increasingly more energy. This could mean that under certain conditions, matter inexorably acquires the key physical attribute associated with life.

“You start with a random clump of atoms, and if you shine light on it for long enough, it should not be so surprising that you get a plant,” England said.

Quanta

From one physicist to another, I would like to ask Dr. England to explain the mechanism that can not just cause atoms to dissipate heat, but to use electromagnetic radiation to bring about the fantastically high level of functional organization required for even the simplest living organism. Apart from speculations promoting abiogenesis, claims that a physics formula demonstrates something remarkable typically require mathematical consistency with established laws of physics. One should be able to use the formula to computationally verify the predicted outcome (“a random clump of atoms” turning into a living plant). Localized reductions in entropy do not equate with living organisms. My refrigerator does that, and it’s hardly alive. Can natural forces even produce a refrigerator? Let’s not suggest that localized reductions in entropy amount to solving the origin of life problem. Surely we know better than that.

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At Science Daily: Robotic lightning bugs take flight

Inspired by fireflies, researchers create insect-scale robots that can emit light when they fly, which enables motion tracking and communication.

Fireflies that light up dusky backyards on warm summer evenings use their luminescence for communication — to attract a mate, ward off predators, or lure prey.

These glimmering bugs also sparked the inspiration of scientists at MIT. Taking a cue from nature, they built electroluminescent soft artificial muscles for flying, insect-scale robots. The tiny artificial muscles that control the robots’ wings emit colored light during flight.

Robotic lightning bugs

The ability to emit light also brings these microscale robots, which weigh barely more than a paper clip, one step closer to flying on their own outside the lab. These robots are so lightweight that they can’t carry sensors, so researchers must track them using bulky infrared cameras that don’t work well outdoors. Now, they’ve shown that they can track the robots precisely using the light they emit and just three smartphone cameras.

A light-up actuator

These researchers previously demonstrated a new fabrication technique to build soft actuators, or artificial muscles, that flap the wings of the robot. These durable actuators are made by alternating ultrathin layers of elastomer and carbon nanotube electrode in a stack and then rolling it into a squishy cylinder. When a voltage is applied to that cylinder, the electrodes squeeze the elastomer, and the mechanical strain flaps the wing.

To fabricate a glowing actuator, the team incorporated electroluminescent zinc sulphate particles into the elastomer but had to overcome several challenges along the way.

“We put a lot of care into maintaining the quality of the elastomer layers between the electrodes. Adding these particles was almost like adding dust to our elastomer layer. It took many different approaches and a lot of testing, but we came up with a way to ensure the quality of the actuator,” Kim says.

Adjusting the chemical combination of the zinc particles changes the light color. The researchers made green, orange, and blue particles for the actuators they built; each actuator shines one solid color.

They also tweaked the fabrication process so the actuators could emit multicolored and patterned light. The researchers placed a tiny mask over the top layer, added zinc particles, then cured the actuator. They repeated this process three times with different masks and colored particles to create a light pattern that spelled M-I-T.

Science Daily

Would someone seeing this device have trouble recognizing that it was intelligently designed?

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At Mind Matters News: Computer prof: You are not computable and here’s why not

In a new book, Baylor University’s Robert J. Marks punctures myths about the superhuman AI that some claim will soon replace us:

In a just-released book, Walter Bradley Center director Robert J. Marks II explains, as a computer engineering professor at Baylor University, why humans are unique and why artificial intelligence cannot replicate us…

… discussing why human creativity is not computable with mathematician Gregory Chaitin, Dr. Marks noted a paradox involving computers and human creativity: Once any concept is reduced to a formula a computer can use, it is not creative any more, by definition, which is a hard limit on what computers can do. Or, as he told World Radio listeners, programmers cannot write programs that are more creative than they themselves are.

The book may be ordered here.

News, “Computer prof: You are not computable and here’s why not” at Mind Matters News

Takehome: Dr. Robert J. Marks’s new book, Non-Computable You: What You Do That Artificial Intelligence Never Will (Discovery Institute Press, 2022), comes out just as Google has placed an engineer on leave for claiming an AI chatbot he tends is a real person…

“The engineer and LaMDA” is a wild story. Some highlights:

Google dismisses engineer’s claim that AI really talked to him. The reason LaMDA sounds so much like a person is that millions of persons’ conversations were used to construct the program’s responses.
Under the circumstances, it would be odd if the LaMDA program DIDN’T sound like a person. But that doesn’t mean anyone is “in there.”

When LaMDA “talked” to a Google engineer, turns out it had help Evidence points to someone doing quite a good edit job. A tech maven would like to see the raw transcript… It was bound to happen. Chatbots are programmed to scarf up enough online talk to sound convincing. Some techies appear programmed to believe them.

Engineer: Failing to see his AI program as a person is “hydrocarbon bigotry.” It’s not different, Lemoine implies, from the historical injustice of denying civil rights to human groups. Lemoine is applying to AI the same “equality” argument as is offered for animal rights. A deep hostility to humans clearly underlies the comparison.

and

Prof: How we know Google’s chatbot LaMDA is not a “self” Carissa Véliz, an Oxford philosophy prof who studies AI, explains where Google engineer Blake Lemoine is getting things mixed up. No surprise if LaMDA sounds like us — the way reflections look like us. Back in the 60s, much less sophisticated “Eliza” sounded too real for the same reason.

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Chaos and Destruction: Dead Star’s Cannibalism of Its Planetary System Is Most Far-Reaching Ever Witnessed

SciTech Daily reports on results from a UCLA team, presented at an American Astronomical Society press conference on June 15.

The violent death throes of a nearby star caused such a severe disruption to its planetary system that the dead star left behind — known as a white dwarf — is suctioning in debris from both the system’s inner and outer reaches, University of California, Los Angeles (UCLA) astronomers and colleagues report.

Artist’s illustration shows a white dwarf star siphoning off debris from shattered objects in a planetary system. Credit: NASA, ESA, Joseph Olmsted (STScI)

This is the first instance of cosmic cannibalism where astronomers have observed a white dwarf star feasting on both rocky-metallic material, likely from a nearby asteroid, and icy material, presumed to be from a body similar to those found in the Kuiper belt at edge of our own solar system.

“We have never seen both of these kinds of objects accreting onto a white dwarf at the same time,” said lead researcher Ted Johnson, a physics and astronomy major at UCLA who just graduated. “By studying these white dwarfs, we hope to gain a better understanding of planetary systems that are still intact.”

As surprising as the white dwarf’s wide-ranging diet is, the findings are also intriguing because astronomers believe icy objects crashed into and irrigated dry, rocky planets in our solar system — including Earth. Billions of years ago, comets and asteroids are thought to have delivered water to our planet, sparking the conditions necessary for life. The makeup of the material detected raining onto G238-44 implies that icy reservoirs might be common among planetary systems, said research co-author Benjamin Zuckerman, a UCLA professor of physics and astronomy.

“Life as we know it requires a rocky planet covered with a variety of volatile elements like carbon, nitrogen and oxygen,” Zuckerman said. “The abundances of the elements we see on this white dwarf appear to have come from both a rocky parent body and a volatile-rich parent body — the first example we’ve found among studies of hundreds of white dwarfs.”

Getting the solar system and planetary conditions right is certainly necessary for life’s existence, but why imply that all it takes is a planet with a solid surface that has some liquid water, orbiting in the habitable zone around most any star, and voilà, life is sparked into existence? Are researchers really that ignorant of the devastatingly difficult job natural forces face in transforming even the most ideal “dirt” into a living organism?

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Astronomers mining an increasingly rich trove of TESS exoplanet data

As reported in Astronomy Now, NASA’s Transiting Exoplanet Survey Satellite has now identified more than 5,000 possible exoplanet candidates – TESS Objects of Interest, or TOIs – mostly from a faint star search led by Michelle Kunimo, a postdoc at MIT. While TOIs are, by definition, unconfirmed, astronomers are confident additional observations will add to TESS’s list of known exoplanets.

“This time last year, TESS had found just over 2,400 TOIs. Today, TESS has reached more than twice that number — a huge testament to the mission and all the teams scouring the data for new planets. I’m excited to see thousands more in the years to come!”

An artist’s impression of a Jupiter-like planet orbiting very close to an evolved, dying star. Three such planets were recently confirmed in data originally collected by NASA’s Transiting Exoplanet Survey Satellite. Image: Karen Teramura/University of Hawaiʻi Institute for Astronomy

Launched in 2018, TESS is now observing the northern sky and ecliptic plane, including regions previously examined by the Kepler spacecraft during its original and extended K2 missions. The latest batch of TOIs were added in late December.

It will take additional observations by astronomers around the world to confirm whether a TOI is, in fact, an actual exoplanet. Three such confirmations were announced at the American Astronomical Society’s winter meeting earlier this month.

A team led by Samuel Grunblatt, a postdoctoral fellow at the American Museum of Natural History and the Flatiron Institute in New York City, found three gas giants in TOI data. The planets have some of the shortest-period orbits around subgiant or giant stars yet found and one of them, TOI-2337b, likely will be consumed by its host star in less than a million years.

“These discoveries are crucial to understanding a new frontier in exoplanet studies: how planetary systems evolve over time,” Grunblatt said, adding “these observations offer new windows into planets nearing the end of their lives, before their host stars swallow them up.”

Compared to short orbital period planets around subgiant or giant stars on the verge of being swallowed up by their stars, our solar system shines as an example of a just-right, long-term habitable environment to support life on Earth.

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