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Researchers have demonstrated that the layered multiferroic material nickel iodide (NiI2) may be the best candidate yet for devices such as magnetic computer memory that are extremely fast and compact. Specifically, they found that NiI2 has greater magnetoelectric coupling than any known material of its kind.

Damping vibrations is crucial for precision experiments, for example in astronomy. A new invention uses a special kind of magnets to achieve this -- electropermanent magnets. They consist of a permanent magnet and a coil. In contrast to electromagnets, they do not have to be permanently supplied with energy. In contrast to permanent magnets, their strength can be tuned: Whenever necessary, a strong electric pulse is sent through the coil, adapting the properties of the magnet.

Damping vibrations is crucial for precision experiments, for example in astronomy. A new invention uses a special kind of magnets to achieve this -- electropermanent magnets. They consist of a permanent magnet and a coil. In contrast to electromagnets, they do not have to be permanently supplied with energy. In contrast to permanent magnets, their strength can be tuned: Whenever necessary, a strong electric pulse is sent through the coil, adapting the properties of the magnet.

This is an open letter to Noa Tishby because, as a passionate defender of Israel, she made a rather serious mistake about biology, and I tried to contact her about it via her publicist. I don’t know if she got my email, so I’m putting it below lest any Jews (or other people) be led to that we carry genes for inherited trauma.  We almost certainly don’t!

Noa Tishby is an Israeli actress who moved to the U.S. and has largely given up acting to advocate for Israel, in which she’s done an exemplary job. She wrote, for example, a primer for the ignorant called Israel: A Simple Guide to the Most Misunderstood Country on Earth, setting out the background of the conflict between Israel and, well, the rest of the world. I read it, and although I already knew much of the material, many people don’t, as evidenced by the widespread and often willful ignorance among “anti-Zionists.” See the first video below!

Noa’s also got chutzpah, as you can tell from this video. She is not easily fazed or discombobulated, even when faced with arrogant stupidity combined with hatred:

In other words, I’m a fan and admire her resolve.

Her error: In the article below, published in the Jewish magazine Sapir, Tishby describes how nerdy she was when young, and now her “uncoolness” persists in her constant defense of Israel, an unpopular stand in much of the world.  While making this reasonable argument, though, Tishby also made a misguided claim about the “inherited” trauma of Jews. It’s a good article (click to read), but the epigenetics stuff bothered me.

Here’s the part that rankled:

What haunts us, even those of us who have lived through only the most recent pogrom, is the familiarity of even the oldest testimony. “We were awakened by a terrifying noise, we didn’t know what was happening . . . ” two millennia ago in Jerusalem. “We realized they’d broken into our neighbors’ house. . . .  We heard them screaming until silence fell. We thought of escaping into the forest, but everyone who tried to escape found it was impossible” one millennium ago in Cologne. This history has shaped us: “Deep inside I know it,” each survivor says in unison as they stand together at the close of the video. The weight of our past is in our blood.

Perhaps literally. Recent studies suggest that these traumatic stories have become woven into our hereditary fabric through epigenetic change. Epigenetic changes are additions to our DNA that influence the way our genetic code is read by our bodies. Studies show that epigenetic change can occur from traumatic experience, and that these changes can be inherited. The idea is intuitive to us: It’s long been suggested that historical traumas can be psychologically passed down from generation to generation. Epigenetic fear is the biological manifestation of historical traumas alongside our genetic code. A review found that “there is now converging evidence supporting the idea that offspring are affected by parental trauma exposures occurring before their birth, and possibly even prior to their conception.” One study found that “in the absence of their own traumatic exposures, offspring of Holocaust survivors” were more likely to exhibit biological signs associated with post-traumatic stress disorder (PTSD). Other studies have suggested that epigenetic changes can be passed down for many generations.

After the pogrom of October 7 and the global reactions to it, our epigenetic inheritance may have been activated in our veins. As the researcher behind the study of offspring of Holocaust survivors observed, “Epigenetic changes often serve to biologically prepare offspring for an environment similar to that of the parents.”

In this respect, Jews have a built-in mechanism that gives acts of barbarism against us a certain familiarity and triggers an almost automatic response. Though the threats have come from different neighbors — Romans, Germans, Baghdadis — across time and place, they have always been similar enough to inoculate us against being truly surprised.

Here’s another version of it on her Facebook page.

Now if you know anything about epigenetics, a form of inheritance of acquired characteristics, you’ll know two things.  First, in nearly all organisms the acquired trait gets passed on for only a single generation, as the modifications of DNA that cause the trait (in this case trauma), is wiped out as the DNA sheds its modifications when producing gametes for the next generation.  Second, there is no evidence that I know of in mammals (including us) that even if a trauma causes something to be inherited by modifying our DNA, that “something” is not the trauma itself, but whatever developmental change happens to be wrought by environmental effects on the DNA.  In the most famous widespread case of “inherited trauma”, the Dutch case of famine during the “hunger winter” of 1944, what was inherited wasn’t the trauma of not getting enough food, but a number of developmental aberrations that lasted only a single generation:

The Dutch Hunger Winter has proved unique in unexpected ways. Because it started and ended so abruptly, it has served as an unplanned experiment in human health. Pregnant women, it turns out, were uniquely vulnerable, and the children they gave birth to have been influenced by famine throughout their lives.

When they became adults, they ended up a few pounds heavier than average. In middle age, they had higher levels of triglycerides and LDL cholesterol. They also experienced higher rates of such conditions as obesity, diabetes and schizophrenia.

By the time they reached old age, those risks had taken a measurable toll, according to the research of L.H. Lumey, an epidemiologist at Columbia University. In 2013, he and his colleagues reviewed death records of hundreds of thousands of Dutch people born in the mid-1940s.

They found that the people who had been in utero during the famine — known as the Dutch Hunger Winter cohort — died at a higher rate than people born before or afterward. “We found a 10 percent increase in mortality after 68 years,” said Dr. Lumey.

The change lasted only one generation; as far as I know, the grandchildren of survivors don’t show this syndrome. Thus, Ms. Tishby erred when implying that the trauma itself faced by Jews could presumably last for a long time, perhaps generations.  If we are indeed traumatized by centuries of antisemitism, it’s certainly because the trauma comes from the environment (i.e., antisemites), and persists because antisemitism persists. Certainly I didn’t want a famous defender of Israel to popularize misguided biology.

So I sent the letter below a while back to Ms. Tishby. Since I couldn’t find a way to contact her directly, I sent it to her public relations person with a request that it be passed on to Tishby. So far I have no reply, and though I didn’t expect one from Tishby, I have no way to know if she ever got my correction.  Ergo I’m publishing it here in hopes that she’ll see it and the “inherited trauma of antissemitism” business will stop.  Yes, call me a Pecksniff. . .

Dear Ms. Tishby,

I’m writing just to urge you to be a bit cautious about the “epigenetic” aspect of Jewish trauma that you mentioned in your otherwise admirable Sapir article. I’m only writing because I’ve long admired your advocacy of Israel in the face of huge pushback, and don’t want you to fall into the errors of others who have mischaracterized epigenetics.

I am Jewish and also an evolutionary geneticist, and know a great deal about epigenetics: environmentally-induced changes in the DNA that usually occur by attaching a methyl group to various parts of DNA. It’s been known, as you said, that this can be inherited: rarely, the effects of parental trauma can cause inherited change in their offspring, though those changes don’t usually involve a child inheriting the trauma itself of their mothers.

What’s more important is that, because DNA changes are “reset” every generation when sperm or eggs are formed, epigenetic modifications usually disappear after one generation, so they can’t be inherited beyond parent—>offspring.  Further, if they do occur (usually through trauma affecting a mother’s physiology or placenta), what is inherited via methylation is not the trauma itself, but various other effects. The famous “Dutch famine study” from the “hunger winter” during the war didn’t involve inheritance of trauma, but a degradation of the offspring’s health that led to various other diseases. In other words, trauma was not inherited, but caused other effects in the children of the traumatized. And that lasted but a single generation.  There’s simply no evidence in humans that trauma itself can be coded into the genome and passed from parent to offspring.

You also mention that ” Other studies have suggested that epigenetic changes can be passed down for many generations.” But the study you cite involved roundworms, and had nothing to do with either humans or trauma (only one study, not “studies” was linked).

In short, there are no studies showing that parental trauma itself is inherited epigenetically. Instead, the effects of trauma on the physiology or development of offspring can be inherited. But they’re inherited, at most, for only one generation. Ergo, it’s a bit misleading to suggest that “the weight of the past is in our blood—literally.” That would be true only, and only in part, for the one generation of offspring of those experiencing the Holocaust. The rest of the Jews would be unaffected, so it wouldn’t be a general phenomenon.  And it would last only for a single generation at most—and what would be inherited wouldn’t be trauma itself but whatever developmental aberrations devolved upon fetuses developing during their mother’s trauma.

It’s really not necessary to invoke dubious science in support of your cause, for we Jews have suffered environmental trauma generation after generation via antisemitism, and this is due to a continuing culture, not to genes.  I myself have been traumatized by the resurgence of antisemitism after October 7, even though I’m at best a secular Jew. But none of my relatives were in the Holocaust, though they came from Eastern Europe.  My own “trauma” comes from seeing the world buy into the big lies about Israel (genocide, apartheid, “disproportinal” killing of Gazans, etc.)

My suggestion, then, is to stay far away from epigenetics as you promulgate your message. And of course your message is vital and important. As I said, I greatly admire your courage in going out there and speaking the truth, and wanted to let you know that the “truth” about epigenetics isn’t very solid!

Best wishes,
Jerry Coyne
Emeritus professor of Ecology and Evolutino
The University of Chicago

I’ve done what I can, and we’ll see if Ms. Tishby continues to spread the fallacious notion of “trauma literally in our blood” (it would have to be in the white cells, since red blood cells lack nuclei!)

Researchers have developed the chatbot Iris, which offers informatics students personalized assistance with programming assignments. A study has now confirmed the chatbot's success: Iris improves the understanding of programming concepts and represents a valuable complement to human tutors.

Snot might not be the first place you'd expect nanobots to be swimming around. But this slimy secretion exists in more places than just your nose and piles of dirty tissues -- it also lines and helps protect the lungs, stomach, intestines and eyes. And now, researchers have demonstrated in mice that their tiny, enzyme-powered 'snot bots' can push through the defensive, sticky layer and potentially deliver drugs more efficiently.

Snot might not be the first place you'd expect nanobots to be swimming around. But this slimy secretion exists in more places than just your nose and piles of dirty tissues -- it also lines and helps protect the lungs, stomach, intestines and eyes. And now, researchers have demonstrated in mice that their tiny, enzyme-powered 'snot bots' can push through the defensive, sticky layer and potentially deliver drugs more efficiently.

Mixing protein-based drugs with hydrogels can keep the atomic bonds in the medication safe from high temperatures or shaking

A drug that inhibits inflammation helped mice live longer and reduced the animals’ incidence of cancer and age-related health problems

An aerial robot weighing 4 grams is powered by tiny solar panels that produce extremely high voltages – an approach that could enable drones to fly indefinitely

The lifestyle choices you make in middle age play a particularly important role in how your brain ages

Hunting in packs seems like a complex social behaviour, but it isn't limited to large carnivores like wolves. A simple sea slug species teams up to swarm its venomous anemone prey as a group

A brand-new paper from Nature Ecology & Evolution used a clever technique to estimate the age of “LUCA”,. the “last universal common ancestor” of all living things. What that means is LUCA is the last creature whose descendants include every species alive: the ancestor of all of us.  And it dates LUCA to about 4.2 billion years ago! That is far older than people thought. Previous estimates were in the 3.5-3.8 billion-year range, after the famous “Late Heavy Bombardment” (LHB), during which the Earth was continually battered with asteroids and comets. It was assumed that nothing alive on Earth could have survived those impacts. But if the authors are right, LUCA’s ancestors did survive this, for 4.2 billion years is probably a big underestimate of of when life on earth began.

The earliest generally accepted fossil evidence for life is about 3.7 billion years, which is based on isotopes that, scientists think, could have been produced only by living creatures. But the earliest genuine fossilized organisms occur a bit later than that: fossilized blue-green algae (“stromatolites”), whose fossils go back 3.5 billion years ago.

The new paper by Moody et al., which has an accompanying research brief (click screenshots below to access, or find the pdf here) pushes the age of LUCA back to 4.2 billion years ago, which actually precedes the LHB. And the new LUCA date comes soon after the Earth actually formed (about 4.54 billion years ago) and after the Moon was created, probably by a huge, Mars-size planet striking Earth and throwing off debris that consolidated to create our Moon. (That occurred soon after the Earth formed.)  Surely no life could have survived that collision, so if the authors are right, it took only about  0.3 billion years, or 300 million years after the Earth was formed, before life existed.

But LUCA wasn’t the first life on Earth: it is simply the bacteria-like species of organism that gave rise to all living creatures. Surely life originated before that, and the new paper suggests that the 4.2 billion year old (byo) LUCA was only one of a number of life forms existing back then, with the rest going extinct without leaving descendants. The authors think this because LUCA probably needed complex carbon compounds to live, and is also likely to have provided niches for other creatures.  That means that life itself began well before LUCA, especially because, based on its genome, the authors conclude that LUCA was quite complex— about as complex as modern bacteria. Surely it would take millions of years of evolution to get to the point where a LUCA-like creature could have existed.  See below for the diagram of what LUCA was like.

The main lesson from the paper is that life began very, very soon after the Earth had cooled off and the dust had settled from the LHB and carving out of the Moon. If that’s the case, then perhaps life on other planets could evolve more easily than we thought.

But on to the paper. If you want the whole megillah, click on the first link, while the second gives a two-page précis.  It’s a very complicated and long paper, so give me kudos for reading it twice to distill it here. But I can’t claim to have understood everything, as the analyses of the data, or even the methodology, is quite arcane and sophisticated.

A two -age summary from the same journal:

Why do we think that all life descended from a single species rather than having multiple origins? Because all living creatures have some similarities that probably reflect the workings of chance: whatever mutations happened to give rise to our ancestor. The paper explains:

The common ancestry of all extant cellular life is evidenced by the universal genetic code, machinery for protein synthesis, shared chirality of the almost-universal set of 20 amino acids [JAC: all amino acids used in modern creatures are the L rather than the D form] and use of ATP as a common energy currency. The last universal common ancestor (LUCA) is the node on the tree of life from which the fundamental prokaryotic domains (Archaea and Bacteria) diverge. As such, our understanding of LUCA impacts our understanding of the early evolution of life on Earth.

The way scientists usually estimate LUCA is using molecular dating based on DNA divergence among living organisms. Because there is a “molecular clock”, with the DNA changing roughly in a linear fashion with time, you can back-calculate from living creatures to estimate when their DNA sequences would have converged on a single sequence, which would be the DNA sequence of LUCA.  But there are formidable problems with this, making DNA-based estimates  contentious. But the authors found a way around this.

What they did is to estimate divergence times of all living creatures (for practicality, they used bacteria [prokaryotes] and Archaea, bacteria-like organisms that form their own kingdom) using DUPLICATED GENES.  These are genes that, tracing the sequences of living organisms back, had already been duplicated in LUCA.  As you may know, genes often get duplicated during cell division or (in sexual organisms) meiosis, so a single gene can now occur in two copies. Those two copies will initially be identical, but then, being genetically independent, will begin to diverge via mutation and then selection or drift. (Examples of duplicated genes are are different forms of globins in humans, two of which, alpha and beta, produce products that combine to make adult hemoglobin.  But many, many genes have duplicated over the history of life.)

A gene that is duplicated (based on sequence similarity) in LUCA must have been present in the ancestor of LUCA, and have duplicated before LUCA existed. Thus an estimate of the age of a duplicated gene in LUCA gives us a lower-bound on the age of LUCA itself. And since some genes are already duplicated in LUCA, we can use them, combined with a molecular clock (and other statistics) to estimate how long it took for each copy to give rise to the diversity of DNA-sequences in descendant copies in modern microbes.  The advantage comes because we have two estimated DNA sequences in LUCA that began identically but then diverged over evolutionary time. This gives us two chances to estimate the age of the creature. Using other methods, we can estimate how many genes there were in LUCA, the size of its genome, and what kind of genes it had.  The latter can then give us an idea of what kind of creature it was and how it lived.

Here are the results, in short:

a.) LUCA lived about 4.2 billion years ago. Here’s the reconstructed phylogeny (note that there are two estimates of its age since they use two copies of each of the five genes they chose for age estimation). Click to enlarge. On the right are all the kingdoms of living organisms, traced back to LUCA.  The use of two gene copies give similar estimates, about 4.2 billion years ago. I’ve circled the two LUCA estimates, which work out to a similar age (see age scale at top for divergence times):

(From paper): Our results suggest that LUCA lived around 4.2 Ga, with a 95% confidence interval spanning 4.09–4.33 Ga under the ILN relaxed-clock model (orange) and 4.18–4.33 Ga under the GBM relaxed-clock model (teal). Under a cross-bracing approach, nodes corresponding to the same species divergences (that is, mirrored nodes) have the same posterior time densities. This figure shows the corresponding posterior time densities of the mirrored nodes for the last universal, archaeal, bacterial and eukaryotic common ancestors (LUCA, LACA, LBCA and LECA, respectively); the last common ancestor of the mitochondrial lineage (Mito-LECA); and the last plastid-bearing common ancestor (LPCA). Purple stars indicate nodes calibrated with fossils. Arc, Archaea; Bac, Bacteria; Euk, Eukarya.

b.) LUCA had a big genome and many genes. The authors estimate that LUCA’s genome had 2.75 million DNA base pairs, capable of making 2,657 proteins (an underestimate of gene number). That is a big and complex organism, comparable to existing bacteria. (Modern E. coli produce about 4288 proteins from 4.6 million base pairs.) This complexity shows that even LUCA was preceded by a long period of evolution.

c.) LUCA was probably an anaerobic and autotrophic creature, which means that it didn’t need oxygen to grow and flourish, and also that it produced its own “food”, getting energy from substances like hydrogen and carbon dioxide.  The authors suggest two places where such a creature could have lived: in warm hydrothermal vents in the ocean, or on the ocean surface, where it would have ample access to the gases that constitute its food.  There was no evidence that the organism was photosynthestic, as it lacked genes involved in modern photosynthesis.

Here’s a sketchy diagram of what kind of genes LUCA had (note the “immune” system, based on CRISPR-like genes that are used to destroy viruses. LUCA probably had a virus problem, too! Figure b) show us how LUCA fit into the tree of life:

(From paper): a, A representation of LUCA based on our ancestral gene content reconstruction. Gene names in black have been inferred to be present in LUCA under the most-stringent threshold (PP = 0.75, sampled in both domains); those in grey are present at the least-stringent threshold (PP = 0.50, without a requirement for presence in both domains). b, LUCA in the context of the tree of life. Branches on the tree of life that have left sampled descendants today are coloured black, those that have left no sampled descendants are in grey. As the common ancestor of extant cellular life, LUCA is the oldest node that can be reconstructed using phylogenetic methods. It would have shared the early Earth with other lineages (highlighted in teal) that have left no descendants among sampled cellular life today. However, these lineages may have left a trace in modern organisms by transferring genes into the sampled tree of life (red lines) before their extinction. c, LUCA’s chemoautotrophic metabolism probably relied on gas exchange with the immediate environment to achieve organic carbon (Corg) fixation via acetogenesis and it may also have run the metabolism in reverse.

d.) LUCA was part of a community of other organisms.  It’s inconceivable that LUCA. which was a sophisticated organism, could live without a source of organic compounds (like amino acids) to use for constructing its body (remember, these organic compounds were not a “food,” but a construction material). Further, LUCA would itself provide organic compounds that would create niches for other species. (It’s likely that viruses, which aren’t good candidates for a LUCA-like creature, already existed.) The phylogeny in figure (b) just above shows how LUCA would fit into the tree of life, giving rise to all modern creatures via speciation  events, but would itself also be part of an earlier family tree, all of whose members save LUCA went extinct without leaving descendants.

These are the four big conclusions of the paper, with the most interesting to me being how short the time was after Earth’s formation for complex life to have evolved.  And the age of LUCA, remember, is an UNDERESTIMATE of how long it took complex life to evolve after the Earth’s conditions were suitable for such evolution.

I’ll end with the authors’ own conclusions, which are lucid enough for the layperson (bolding is mine)

Conclusions:

By treating gene presence probabilistically, our reconstruction maps many more genes (2,657) to LUCA than previous analyses and results in an estimate of LUCA’s genome size (2.75 Mb) that is within the range of modern prokaryotes. The result is a picture of a cellular organism that was prokaryote grade rather than progenotic  [JAC: not having the characteristic of a prokaryote, which LUCA did] and that probably existed as a component of an ecosystem, using the WLP [JAC: the Wood-Ljungdahl pathway for producing energy, based on hydrogen and carbon dioxide] for acetogenic [JAC: producing acetate as a product of anaerobic metabolism] growth and carbon fixation. We cannot use phylogenetics to reconstruct other members of this early ecosystem but we can infer their physiologies based on the metabolic inputs and outputs of LUCA. How evolution proceeded from the origin of life to early communities at the time of LUCA remains an open question, but the inferred age of LUCA (~4.2 Ga) compared with the origin of the Earth and Moon suggests that the process required a surprisingly short interval of geologic time.

Oh, and the authors suggest the intriguing possibility that if we could reconstruct the DNA sequence of LUCA—something that is not beyond the realm of possibility—then perhaps we could perhaps make in the lab a LUCA-like organism, and actually see what our ancestor looked like!

Today’s Jesus and Mo strip, called, “road2,” has an accompanying note that says this: “A resurrection from 2006, when the boys first got in their car.”  As far as I can understand this one, Mo never saw an uncovered women before he passed his test, and so his ogling endangers both of the Divine Duo.

https://traffic.libsyn.com/secure/sciencesalon/mss448_Michael_Shermer_2024_07_17.mp3 Download MP3

Why do people believe the assassination attempt on Donald Trump was a conspiracy?

The assassination attempt on President Donald Trump on July 13 has already spawned a bevy of conspiracy theories. The blood on his ear was that of a theatrical gel pack, which you can supposedly see in his hand as he touches his ear. Trump’s defiant response was staged, as evidenced by the fact that the Secret Service let him back up after tackling him to the ground. The Secret Service let it happen on purpose (LIHOP in conspiracy circles) by waiting for the assassin to take his shot before returning fire. The ladder for the shooter to get on the roof was planted by covert operatives. This was yet another hit ordered by Vladimir Putin. The Chinese want to make sure Trump doesn’t return to the Presidency so they can take Taiwan. The shooter was part of Antifa. Never-Trumper Republicans were behind it. It was a false flag operation.

It is early still, and there is much we do not know about Trump’s would-be assassin, Thomas Matthew Crooks, but the odds are long that he was a lone actor and not part of a conspiracy. The 20-year old was, in fact, described by acquaintances as a “loner” in high school who was bullied and had “a few friends” but “didn’t have a whole friend group.” He was a registered Republican but donated $15 to the Democratic Progressive Turnout Project in 2021. He had possession of his father’s legally-purchased AR-15 style rifle, and had in his car dozens of rounds of ammunition and bomb-making materials. Most revealingly, Crooks was allegedly rejected by his high school riflery club for being “comically bad” with a gun. Does this sound like the profile of a hitman that a crack team of conspirators would contract with to assassinate a former president?

To be sure, there are a number legitimate questions surrounding the Trump assassination attempt that do not involve conspiracies:

1. Why did the cop who confronted the shooter on the roof not have his gun at the ready so he could engage him instead of standing down?
2. The shooter appears to have accessed the rooftop via a large ladder, but how did that ladder get there in the first place?
3. The building on which Crooks was perched was, in fact, a staging area for local police, so how did they miss the would-be assassin climbing onto the roof?
4. Since the Secret Service sharpshooter killed the assassin within seconds of shots fired, why did he not take the shot first?
5. Why did the Secret Service allow Trump to jump back up to pump his fist and mouth “fight fight fight” to the crowd when they should have whisked him away to his bullet-proof SUV?
6. Why did the police not take seriously all the bystanders who saw the gunman on the roof and alerted them about it.

These “BlueAnon” conspiracy theories, so named for their doppleganger echo of QAnon conspiracism, are as predictable as they are irrational. The day before the assassination attempt, in fact, I was in attendance as a speaker at the annual Freedom Fest conference in Las Vegas, Nevada, along with Presidential candidate Robert F. Kennedy, Jr., who famously believes that the CIA assassinated his uncle John F. Kennedy and his father Robert F. Kennedy. The CIA has done some questionable things in foreign countries in the name of national interests there, but murdering their own president and possible future president? Why do otherwise rational people believe such seemingly irrational things?

In my book, Conspiracy: Why the Rational Believe the Irrational, I attempt to answer this question by outlining a number of cognitive and emotional factors at work, including:

Event magnitude. The larger the event the more conspiracism surrounds it, as people invest more time and energy into everything that happened surrounding the event in search of some deeper cause. The assassinations of JFK, MLK, and RFK, and terrorist attacks like 9/11, are so large in scope and interest that they draw our attention to examine every detail so scrupulously that everything becomes pregnant with meaning.

Proportionality bias. Large events need large causes. The Holocaust was one of the worst genocides in history and it was caused by one of the worst political regimes in history. There’s a proportionality balance there. The assassination of President Lincoln by a cabal of southern supporters in hopes of reigniting the South’s “war of independence” feels balanced. That JFK, MLK, and RFK were assassinated by lone gunmen, or that Princess Diana’s death in a car crash was the result of drunk driving and her not wearing a seatbelt, or that 9/11 was orchestrated by 19 guys with box cutters, doesn’t feel proportional, so we turn to deeper conspiratorial causes.

Anomaly hunting. Large events lead people to look for anything unusual, especially if it is unexplainable, then glomming on to that anomaly as “evidence” of a conspiracy. How did that ladder get there for the Trump shooter to climb up on the roof? Why didn’t that police officer stop the shooter when he confronted him? Why didn’t the Secret Service take out the shooter before he shot at Trump? Why was Trump allowed to jump back up to make a fist pump after being shot?

Personal incredulity. If I can’t think of an explanation for anomaly X besides a conspiracy, then that proves there is a conspiracy.

Hindsight Bias. The tendency to reconstruct the past to fit with present knowledge. Once an event has occurred, we look back and reconstruct how it happened, why it had to happen that way and not some other way, and why we should have seen it coming all along.

Patternicity and agenticity. The tendency to find meaningful patterns in random noise, and to infuse those patterns with intentional agents, leads to conspiratorial cognition.

Uncertainty bias. In the early days of a major event much is unknown, and that leads people to fill in the blanks with whatever comes to mind.

Teleological thinking. The belief that everything happens for a reason and nothing of importance happens by chance.

With all of these factors at work, it was inevitable that within minutes of the assassination attempt on Donald Trump conspiricism would flood social media. While it is not completely irrational to believe in some conspiracy theories—given that conspiracies do happen and it is often better to be safe than sorry—it is very likely that the attempt to kill President Trump was not part of some nefarious cabal and instead was the act of an unhinged lone actor. Keep in mind that in U.S. history four presidents have been assassinated while in office—Abraham Lincoln, James Garfield, William McKinley and John F. Kennedy—only one of which was the result of a conspiracy (Lincoln). And another five presidents survived assassination attempts—Andrew Jackson, Theodore Roosevelt, Franklin Roosevelt, Gerald Ford, and Ronald Reagan—all of which were by lone assassins. As was the assassination of presidential candidate Robert F. Kennedy on June 5, 1968, after a campaign rally at the Ambassador Hotel in Los Angeles. Kennedy was murdered by a Palestinian named Sirhan Sirhan, who testified in his trial that he killed Kennedy “with 20 years of malice aforethought.”

Thus, it is rational to apply the Conspiracism Principle first: Never attribute to malice what can be explained by randomness or incompetence.

Well, this is about it, folks. This feature, which has been going daily for over a decade, is about to go extinct. It is sad because in general contributions and commenting (especially on science posts) seem to be waning, and an unread website is a dying website.

Fortunately, reader Damon Williford from Texas sent a photo contribution a few minutes ago!  His captions are indented, and you can enlarge the photos by clicking on them.

Attached are a few photos of butterflies taken in May at a local park in Bay City, Texas.

Clouded Skipper (Lerema accius):

A pair of mating Clouded Skippers:

Fiery Skipper (Hylephila phyleus) feeding on nectar from lantana (Lantana spp.):

Tropical Checkered-skipper (Burnsius oileus):

Common Buckeye (Junonia coenia):

All photos were taken with a Canon EOS R7 and Canon f/5.6-8 IS USM. I used iNaturalist to identify the insects.

Was COVID cooked up in a lab? Do “they” have a cure for cancer and are hiding it from the public? Do pharmaceutical companies make up diseases to market otherwise failed drugs? Did insurance companies scheme with infectious disease professional organizations to suppress treatments for chronic Lyme disease? Did the supplement industry lobby congress to weaken regulations of their own products? OK, […]

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Exploring exoplanet atmospheres in more detail was one task that planetary scientists anticipated during the long wait while the James Webb Space Telescope (JWST) was in development. Now, their patience is finally paying off. News about discoveries of exoplanet atmosphere using data from JWST seems to be coming from one research group or another almost every week, and this week is no exception. A paper published in Nature by authors from a few dozen institutions describes the atmospheric differences between the “morning” and “evening” sides of a tidally locked planet for the first time.

First, let’s clarify what the “morning” and “evening” sides mean. Tidally locked planets don’t spin, so one hemisphere constantly faces the planet’s star. As such, there is always a part of the planet where it appears to be “morning,” with the star barely peaking over the horizon. Alternatively, there’s a part of the planet where it seems to be “evening,” where the star is again just barely peaking over the horizon, but it would appear to be setting. 

Typically, on Earth, we would think of the morning side as the star peaking over the eastern side, whereas the evening side would see the star setting into the western sky. However, exoplanets sometimes rotate in the opposite direction from planets in our solar system, so that mental model doesn’t always work for them.

The JWST light curve for WASP-34b, clearly showing the dip in the star’s brightness as the planet passes in front of it.
Credit – NASA / ESA / CSA / R. Crawford (STScI)

It’s also important not to confuse the “morning” and “evening” sides with the “day” and “night” sides of the planet. On the day side, the full force of the star affects the planet, but on the night side, the star is never seen at all. The temperature differences on such a planet are massive, and cause much more extreme weather than anything we have experience with in our solar system.

That is the case for WASP-39b, one of the most studied exoplanets. It is a “hot Jupiter” and is roughly 1.3 times the size of the largest planet in our solar system, though it only masses in at about the same size as Saturn. It’s 700 light years away and is tidally locked to its star.

Exoplanet hunters have intently studied this exoplanet since its discovery in 2011. It was the target of JWST’s first exoplanet research when it began science operations. Since then, they’ve made several interesting discoveries, and the Nature paper describes a new one—that the “morning” side of WASP-39b is a few hundred degrees cooler than its “evening” side.

Fraser talks exoplanet atmosphere with expert Dr. Joanna Barstow.

This temperature discrepancy is likely due to atmospheric conditions on the planet itself. The paper’s authors believe there is an extremely strong wind on the planet that runs from day to night at thousands of miles an hour. The wind rotates from the day side through the evening side to the night side, then through the morning side back to the day side.

So, essentially, the morning side receives “air” that has been cooled while traveling through the planet’s night side. However, that air is still a blistering 600 C (1,150 F). The temperature on the evening side, though, is hotter at 800 C (1,450 F), much hotter than any conditions found on any planet in our solar system.

Detecting such a temperature difference on an exoplanet hundred of light years away is an impressive technical feat, and the study’s lead author, Néstor Espinoza, credits JWST’s capabilities for enabling it. The telescope watched the planet both while it was traversing in front of its star, but also while it was next to it and emitting its own, admittedly much fainter, light. 

JWST found methane in a different exoplanet atmosphere, as Fraser describes in this video.

They were differentiating between the starlight filtered through the atmosphere of the planet and when there was no filtered starlight coming through allowed the researchers to make temperature estimates. JWST is so sensitive they were also able to split the data into semi-circles to differentiate the” “morning” side from the “evening” side. They also noticed that the “evening” side was slightly puffier, indicating that it was hotter than its counterpart.

The authors plan to use WASP-39b as a basis for studying future exoplanet atmospheres, and there are plenty more in JWST’s dataset to look at. In addition, another round of data collection, Webb Cycle 2 General Observers Program 3969, will also focus on the atmospheres of other hot Jupiters. Finally, planetary scientists won’t have to wait for their treasure trove of data anymore.

Learn More:
NASA – NASA’s Webb Investigates Eternal Sunrises, Sunsets on Distant World
Espinoza et al. – Inhomogeneous terminators on the exoplanet WASP-39 b
UT – Sulphur Makes A Surprise Appearance in this Exoplanet’s Atmosphere
UT – The Atmosphere of an Exoplanet Reveals Secrets About Its Surface

Lead Image:
Artists concept of WASP-39b.
Credits: NASA, ESA, CSA, R. Crawford (STScI)

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Next time you’re visiting the seaside or a large lake, or even sipping a frosty glass of water, think about where it all originated. There are many pathways that water could have taken to the infant Earth: via comets, “wet asteroids”, and outgassing from early volcanism. Aster Taylor, a University of Michigan graduate student has another idea: dark comets. They’re something of a cross between asteroids and comets and could have played a role in water delivery to our planet.

Dark comets are small Solar System bodies. They have short rotational periods thanks to non-gravitational pushes by sublimation that creates jets. These mysterious objects probably make up more than half of all near-Earth objects.

Dark Comets and Asteroids

Planetary scientists consider dark comets as a population of active asteroids. Yet, they aren’t in the same category as regular asteroids and comets. They’re on near-Earth orbits, so when one passes close to the Sun, it doesn’t grow a coma. That lack of a coma is why they’re called “dark comets.” Yet, their sublimation jets appear to be a response to radiation from the Sun. They’re likely rich in water ice so that raises an interesting question. Could these also have been a source of water for Earth in the distant past?

“We don’t know if these dark comets delivered water to Earth,” said Taylor. “But we can say that there is still debate over how exactly the Earth’s water got here,” Taylor said. “The work we’ve done has shown that this is another pathway to get ice from somewhere in the rest of the Solar System to the Earth’s environment.”

Water Delivery From Small Bodies

The story of how Earth got its water is still unfolding. One theory says infant Earth formed with molecular precursors to water. Another one says that water-laden asteroids and comets brought water to Earth during or just after formation. That’s interesting because most asteroids exist near the so-called “ice line”—a region well beyond Earth where liquids freeze. Something propelled them to the inner solar system. When they got close to the Sun, their ice sublimated. That’s actually what happens with a comet, too. So, maybe both comets and planetesimals were water-bearers during Earth’s formation. Volcanic activity could have released their trapped water as vapor.

An artist’s rendering of the early Moon and Earth, which sustained many asteroid impacts. Many of those asteroids and possibly dark comets contributed their water to the infant Earth. As it cooled, the water outgassed as vapor. Credit: Simone Marchi (SwRI)/SSERVI/NASA

How about the wet asteroids, though? Where did they come from? We know that comets formed out in the cooler reaches of the protosolar nebula. Somehow they make their way (through gravitational perturbations and dynamical action) to the inner solar system. There, they have collided with Earth (just like Comet Shoemaker-Levy 9 encountered Jupiter in 1994).

That leaves the water ice-rich asteroids or “dark comets”. Most water-rich asteroids or “dark comets” exist in the Asteroid Belt. However, plenty of them orbit in the inner solar system, too. Those near-Earth objects probably made their way sunward due to gravitational interactions with Jupiter or other worlds. Those with some amount of water ice trapped on or below their surfaces could have been a delivery mechanism for water to early Earth.

An artist’s concept of a rocky planet and a rain of comets and other objects pummeling its surface. These, along with dark comets, could have delivered water to early Earth. Courtesy NASA/JPL. Searching for Water-rich Dark Comets

The same would be true of the dark comets, according to Taylor. “We think these objects came from the inner and/or outer main Asteroid Belt, and the implication of that is that this is another mechanism for getting some ice into the inner solar system,” he said. “There may be more ice in the inner main belt than we thought. There may be more objects like this out there. This could be a significant fraction of the nearest population. We don’t really know, but we have many more questions because of these findings.”

To test their ideas about dark comets, Taylor and fellow team members created dynamical models that looked at different populations of these objects and modeled possible paths they could have taken to get to Earth. Many of these objects in the model ended up where today’s dark comets exist—on orbits that bring them into the inner solar system. Their model showed the team that many of these objects ended up where dark comets are today and that the main Asteroid Belt is their source.

One Object Implicates Many

The team’s work also suggests that one large object may come from the Jupiter-family comets, with orbits that take them close to Jupiter. It’s called 2003 RM, and follows an elliptical orbit that brings it close to Earth, then out to Jupiter and back past Earth. Its orbit is pretty typical of a Jupiter family comet that was knocked inward from its orbit.

Taylor’s team studies focused on seven dark comets. The result of their work suggests that between 0.5% and 60% of all near-Earth objects could be dark comets that aren’t accelerated by gravitational interactions. Instead, these objects experience non-gravitational accelerations—that is, they are moved along by the “jet action” of ice as it sublimates. The researchers suggest that these dark comets likely came from the asteroid belt but that they moved due to those nongravitational accelerations. They also think that other asteroids in the Belt also contain ice.

More About Dark Comets

The population of dark comets includes small, fast-rotating objects, especially when compared to larger asteroids. Comets are known to rotate fairly fast because they start to lose their ice to sublimation as they near the Sun. As we saw when the Rosetta spacecraft studied Comet 67P/Churyumov-Gerasimenko, a comet nucleus sprouts little jets as part of the sublimation process. Those jets have the effect of pushing the comet nucleus along. It also accelerates it, giving the object that non-gravitational acceleration mentioned above. Sublimation can also cause the object to spin quite fast. If it rotates quickly enough, the object (comet nucleus or rubble pile asteroid) breaks apart.

Image of Comet 67P/Churyumov-Gerasimenko taken by the European Space Agency’s (ESA) Rosetta spacecraft on Jan. 31, 2015. There’s a jet of material streaming from the comet as it’s warmed by the Sun. It’s not a dark comet, but still experiences sublimation. (Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0)

“These pieces will also have ice on them, so they will also spin out faster and faster until they break into more pieces,” Taylor said. “You can just keep doing this as you get smaller and smaller and smaller. What we suggest is that the way you get these small, fast rotating objects is you take a few bigger objects and break them into pieces.”

As these dark objects lose their ice, they get even smaller and rotate more rapidly. Taylor’s team thinks that while the larger dark comet, 2003 RM, was likely a larger object that got kicked out of the outer main belt of the Asteroid Belt, the six other objects they studied likely came from the inner main belt. They probably were part of a larger object that got knocked inward and broke apart. Further study of this and similar dark comets should help determine what contribution these objects played in the delivery of Earth’s water.

For More Information

The Origins of Dark Comets
The Dynamical Origins of the Dark Comets and a Proposed Evolutionary Track

The post More Than Half of Near Earth Objects Could Be “Dark Comets” appeared first on Universe Today.

The James Webb Space Telescope (JWST) has accomplished some spectacular feats since it began operations in 2021. Thanks to its sensitivity in the near- and mid-infrared wavelengths, it can take detailed images of cooler objects and reveal things that would otherwise go unnoticed. This includes the iconic image Webb took of Jupiter in August 2022, which showed the planet’s atmospheric features (including its polar aurorae and Great Red Spot) in a new light. Using Webb, a team of European astronomers recently observed the region above the Great Red Spot and discovered previously unseen features.

The team was led by Dr. Henrik Melin, an STFC JWST Fellow and Planetary Scientist from the University of Leicester. He was joined by researchers from the University of Reading, the Space Telescope Science Institute (STScI), the JAXA Institute of Space and Astronautical Science, the Center for Space Physics at Boston University, the Observatoire de Paris, the SETI Institute, NASA’s Jet Propulsion Laboratory, and multiple universities. The paper that describes their observations recently appeared in the journal Nature Astronomy.

The team conducted integral field spectroscopy (IFS) of Jupiter’s Great Red Spot using Webb’s Near-InfraRed Spectrograph (NIRSpec) in July 2022. This process involves dissecting an astronomical image into multiple spatial components and dispersing them with a spectrograph to provide spatially resolved information. Their observations were made as part of an Early Release Science program titled “ERS Observations of the Jovian System as a Demonstration of JWST’s Capabilities for Solar System Science.”

Interestingly, the discovery was completely unexpected, as the team attempted to study Jupiter’s upper atmosphere in more detail. Compared to Jupiter’s bright aurorae, the glow from the planet’s ionosphere is weak, making it difficult for ground-based telescopes to conduct detailed observations of this region. Scientists have been especially interested in studying Jupiter’s ionosphere since it is where Jupiter’s atmosphere and magnetic field begin to interact. It is within this layer that Jupiter’s polar aurorae can be seen, which are fueled by material ejected by Io’s many active volcanoes.

Closer to the equator, the structure of the planet’s upper atmosphere is influenced by incoming sunlight. Because Jupiter receives only 4% as much sunlight as Earth, astronomers expected this region of the atmosphere to be homogenous. However, the team was surprised that this region contained intricate wave patterns, including dark arcs, bright spots, and other structures. As Dr. Melin explained in an ESA press release:

“We thought this region, perhaps naively, would be really boring. It is in fact just as interesting as the northern lights, if not more so. Jupiter never ceases to surprise. One way in which you can change this structure is by gravity waves – similar to waves crashing on a beach, creating ripples in the sand. These waves are generated deep in the turbulent lower atmosphere, all around the Great Red Spot, and they can travel up in altitude, changing the structure and emissions of the upper atmosphere.”

Since sunlight drives the light emitted from the planet’s ionosphere, the team suspects that another mechanism is responsible for altering the shape and structure of this region. In the future, the team hopes to conduct follow-up observations of these wave patterns to investigate how they move within Jupiter’s upper atmosphere and how they change over time. These findings could also inform the ESA’s Jupiter Icy Moons Explorer (JUICE), which will reach Jupiter and begin conducting detailed observations in 2031.

Further Reading: ESA

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