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After a journey lasting about two billion years, photons from an extremely energetic gamma-ray burst (GRB) struck the sensors on the Neil Gehrels Swift Observatory and the Fermi Gamma-Ray Space Telescope on October 9th, 2022. The GRB lasted seven minutes but was visible for much longer. Even amateur astronomers spotted the powerful burst in visible frequencies.

It was so powerful that it affected Earth’s atmosphere, a remarkable feat for something more than two billion light-years away. It’s the brightest GRB ever observed, and since then, astrophysicists have searched for its source.

NASA says GRBs are the most powerful explosions in the Universe. They were first detected in the late 1960s by American satellites launched to keep an eye on the USSR. The Americans were concerned that the Russians might keep testing atomic weapons despite signing 1963’s Nuclear Test Ban Treaty.

Now, we detect about one GRB daily, and they’re always in distant galaxies. Astrophysicists struggled to explain them, coming up with different hypotheses. There was so much research into them that by the year 2,000, an average of 1.5 articles on GRBs were published in scientific journals daily.

There were many different proposed causes. Some thought that GRBs could be released when comets collided with neutron stars. Others thought they could come from massive stars collapsing to become black holes. In fact, scientists wondered if quasars, supernovae, pulsars, and even globular clusters could be the cause of GRBs or associated with them somehow.

GRBs are confounding because their light curves are so complex. No two are identical. But astrophysicists made progress, and they’ve learned a few things. Short-duration GRBs are caused by the merger of two neutron stars or the merger of a neutron star and a black hole. Longer-duration GRBs are caused by a massive star collapsing and forming a black hole.

This sample of 12 GRB light curves shows how no two are the same. Image Credit: NASA

New research in Nature examined the ultra-energetic GRB 221009A, dubbed the “B.O.A.T: Brightest Of All Time,” and found something surprising. When it was initially discovered, scientists said it was caused by a massive star collapsing into a black hole. The new research doesn’t contradict that. But it presents a new mystery: why are there no heavy elements in the newly uncovered supernova?

The research is “JWST detection of a supernova associated with GRB 221009A without an r-process signature.” The lead author is Peter Blanchard, a Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) postdoctoral fellow.

“The GRB was so bright that it obscured any potential supernova signature in the first weeks and months after the burst,” Blanchard said. “At these times, the so-called afterglow of the GRB was like the headlights of a car coming straight at you, preventing you from seeing the car itself. So, we had to wait for it to fade significantly to give us a chance of seeing the supernova.”

“When we confirmed that the GRB was generated by the collapse of a massive star, that gave us the opportunity to test a hypothesis for how some of the heaviest elements in the universe are formed,” said lead author Blanchard. “We did not see signatures of these heavy elements, suggesting that extremely energetic GRBs like the B.O.A.T. do not produce these elements. That doesn’t mean that all GRBs do not produce them, but it’s a key piece of information as we continue to understand where these heavy elements come from. Future observations with JWST will determine if the B.O.A.T.’s ‘normal’ cousins produce these elements.”

Scientists know that supernova explosions forge heavy elements. They’re an important source of elements from oxygen (atomic number 8) to rubidium (atomic number 37) in the interstellar medium. They also produce heavier elements than that. Heavy elements are necessary to form rocky planets like Earth and for life itself. But it’s important to note that astrophysicists don’t completely understand how heavy elements are produced.

This periodic table from the NASA Scientific Visualization Studio shows where the elements come from, though scientists still have some uncertainty. Image Credit: NASA’s Goddard Space Flight Center

Scientists naturally wondered if an extremely luminous GRB like GRB 221009A would produce even more heavy elements. But that’s not what they found.

“This event is particularly exciting because some had hypothesized that a luminous gamma-ray burst like the B.O.A.T. could make a lot of heavy elements like gold and platinum,” said second author Ashley Villar of Harvard University and the Center for Astrophysics | Harvard & Smithsonian. “If they were correct, the B.O.A.T. should have been a goldmine. It is really striking that we didn’t see any evidence for these heavy elements.”

Stars forge heavy elements by nucleosynthesis. Three processes are responsible for that: the p-process, the s-process and the r-process (proton capture process, slow neutron capture process, and the rapid neutron capture process.) The r-process captures neutrons faster than the s-process and is responsible for about half of the elements heavier than iron. The r-process is also responsible for the most stable isotopes of these heavy elements.

That’s all to illustrate the importance of the r-process in the Universe.

The researchers used the JWST to get to the bottom of GRB 221009A. The GRB was obscured by the Milky Way, but the JWST senses infrared light and saw right through the Milky Way’s gas and dust. The telescope’s NIRSpec (Near Infrared Spectrograph) senses elements like oxygen and calcium, usually found in supernovae. But the signatures weren’t very bright, a surprise considering how bright the supernova was.

“It’s not any brighter than previous supernovae,” lead author Blanchard said. “It looks fairly normal in the context of other supernovae associated with less energetic GRBs. You might expect that the same collapsing star producing a very energetic and bright GRB would also produce a very energetic and bright supernova. But it turns out that’s not the case. We have this extremely luminous GRB, but a normal supernova.”

Confirming the presence of the supernova was a big step to understanding GRB 221009A. But the lack of an r-process signature is still confounding.

Scientists have only confirmed the r-process in the merger of two neutron stars, called a kilonova explosion. But there are too few neutron star mergers to explain the abundance of heavy elements.

This artist’s illustration shows two neutron stars colliding. Known as a “kilonova” event, they’re the only confirmed location of the r-process that forges heavy elements. Credits: Elizabeth Wheatley (STScI)

“There is likely another source,” Blanchard said. “It takes a very long time for binary neutron stars to merge. Two stars in a binary system first have to explode to leave behind neutron stars. Then, it can take billions and billions of years for the two neutron stars to slowly get closer and closer and finally merge. But observations of very old stars indicate that parts of the universe were enriched with heavy metals before most binary neutron stars would have had time to merge. That’s pointing us to an alternative channel.”

Researchers have wondered if luminous supernovae like this can account for the rest. Supernovae have an inner layer where more heavy elements could be synthesized. But that layer is obscured. Only after things calm down is the inner layer visible.

“The exploded material of the star is opaque at early times, so you can only see the outer layers,” Blanchard said. “But once it expands and cools, it becomes transparent. Then you can see the photons coming from the inner layer of the supernova.”

All elements have spectroscopic signatures, and the JWST’s NIRSpec is a very capable instrument. But it couldn’t detect heavier elements, even in the supernova’s inner layer.

“Upon examining the B.O.A.T.’s spectrum, we did not see any signature of heavy elements, suggesting extreme events like GRB 221009A are not primary sources,” lead author Blanshard said. “This is crucial information as we continue to try to pin down where the heaviest elements are formed.”

Scientists are still uncertain about the GRB and its lack of heavy elements. But there’s another feature that might offer a clue: jets.

“A second proposed site of the r-process is in rapidly rotating cores of massive stars that collapse into an accreting black hole, producing similar conditions as the aftermath of a BNS merger,” the authors write in their paper. “Theoretical simulations suggest that accretion disk outflows in these so-called ‘collapsars’ may reach the neutron-rich state required for the r-process to occur.”

The “accretion disk outflows” the researchers refer to are relativistic jets. The narrower the jets are, the brighter and more focused their energy is.

Could they play a role in forging heavy elements?

“It’s like focusing a flashlight’s beam into a narrow column, as opposed to a broad beam that washes across a whole wall,” Laskar said. “In fact, this was one of the narrowest jets seen for a gamma-ray burst so far, which gives us a hint as to why the afterglow appeared as bright as it did. There may be other factors responsible as well, a question that researchers will be studying for years to come.”

The researchers also used NIRSpec to gather a spectrum from the GRB’s host galaxy. It has the lowest metallicity of any galaxy known to host a GRB. Could that be a factor?

“This is one of the lowest metallicity environments of any LGRB, which is a class of objects that prefer low-metallicity galaxies, and it is, to our knowledge, the lowest metallicity environment of a GRB-SN to date,” the authors write in their research. “This may suggest that very low metallicity is required to produce a very energetic GRB.”

The host galaxy is also actively forming stars. Is that another clue?

“The spectrum shows signs of star formation, hinting that the birth environment of the original star may be different than previous events,” Blanshard said.

Yijia Li is a graduate student at Penn State and a co-author of the paper. “This is another unique aspect of the B.O.A.T. that may help explain its properties,” Li said. “The energy released in the B.O.A.T. was completely off the charts, one of the most energetic events humans have ever seen. The fact that it also appears to be born out of near-primordial gas may be an important clue to understanding its superlative properties.”

This is another case where solving one mystery leads to another unanswered one. The JWST was launched to answer some of our foundational questions about the Universe. By confirming that a supernova is behind the most powerful GRB ever detected, it’s done part of its job.

But it also found another mystery and has left us hanging again.

The JWST is working as intended.

The post The Brightest Gamma Ray Burst Ever Seen Came from a Collapsing Star appeared first on Universe Today.

It’s an exciting time for the fields of astronomy, astrophysics, and cosmology. Thanks to cutting-edge observatories, instruments, and new techniques, scientists are getting closer to experimentally verifying theories that remain largely untested. These theories address some of the most pressing questions scientists have about the Universe and the physical laws governing it – like the nature of gravity, Dark Matter, and Dark Energy. For decades, scientists have postulated that either there is additional physics at work or that our predominant cosmological model needs to be revised.

While the investigation into the existence and nature of Dark Matter and Dark Energy is ongoing, there are also attempts to resolve these mysteries with the possible existence of new physics. In a recent paper, a team of NASA researchers proposed how spacecraft could search for evidence of additional physical within our Solar Systems. This search, they argue, would be assisted by the spacecraft flying in a tetrahedral formation and using interferometers. Such a mission could help resolve a cosmological mystery that has eluded scientists for over half a century.

The proposal is the work of Slava G. Turyshev, an adjunct professor of physics and astronomy at the University of California Los Angeles (UCLA) and research scientist with NASA’s Jet Propulsion Laboratory. He was joined by Sheng-wey Chiow, an experimental physicist at NASA JPL, and Nan Yu, an adjunct professor at the University of South Carolina and a senior research scientist at NASA JPL. Their research paper recently appeared online and has been accepted for publication in Physical Review D.

A new study shows how measuring the Sun’s gravitational field could search for additional physics. Credit: NASA/ESA

Turyshev’s experience includes being a Gravity Recovery And Interior Laboratory (GRAIL) mission science team member. In previous work, Turyshev and his colleagues have investigated how a mission to the Sun’s solar gravitational lens (SGL) could revolutionize astronomy. The concept paper was awarded a Phase III grant in 2020 by NASA’s Innovative Advanced Concepts (NIAC) program. In a previous study, he and SETI astronomer Claudio Maccone also considered how advanced civilizations could use SGLs to transmit power from one solar system to the next.

To summarize, gravitational lensing is a phenomenon where gravitational fields alter the curvature of spacetime in their vicinity. This effect was originally predicted by Einstein in 1916 and was used by Arthur Eddington in 1919 to confirm his General Relativity (GR). However, between the 1960s and 1990s, observations of the rotational curves of galaxies and the expansion of the Universe gave rise to new theories regarding the nature of gravity over larger cosmic scales. On the one hand, scientists postulated the existence of Dark Matter and Dark Energy to reconcile their observations with GR.

On the other hand, scientists have advanced alternate theories of gravity (such as Modified Newtonian Dynamics (MOND), Modified Gravity (MOG), etc.). Meanwhile, others have suggested there may be additional physics in the cosmos that we are not yet aware of. As Turyshev told Universe Today via email:

“We are eager to explore questions surrounding the mysteries of dark energy and dark matter. Despite their discovery in the last century, their underlying causes remain elusive. Should these ‘anomalies’ stem from new physics—phenomena yet to be observed in ground-based laboratories or particle accelerators—it’s possible that this novel force could manifest on a solar system scale.”

Artist’s impression of a proposed Solar Gravity Lens telescope. Credit: The Aerospace Corporation

For their latest study, Turyshev and his colleagues investigated how a series of spacecraft flying in a tetrahedral formation could investigate the Sun’s gravitational field. These investigations, said Turyshev, would search for deviations from the predictions of general relativity at the Solar System scale, something that has not been possible to date:

“These deviations are hypothesized to manifest as nonzero elements in the gravity gradient tensor (GGT), fundamentally akin to a solution of the Poisson equation. Due to their minuscule nature, detecting these deviations demands precision far surpassing current capabilities—by at least five orders of magnitude. At such a heightened level of accuracy, numerous well-known effects will introduce significant noise. The strategy involves conducting differential measurements to negate the impact of known forces, thereby revealing the subtle, yet nonzero, contributions to the GGT.”

The mission, said Turyshev, would employ local measurement techniques that rely on a series of interferometers. This includes interferometric laser ranging, a technique demonstrated by the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission, a spacecraft pair that relies on laser range finding to track Earth’s oceans, glaciers, rivers, and surface water. The same technique will also be used to investigate gravitational waves by the proposed space-based Laser Interferometry Space Antenna (LISA).

The spacecraft will also be equipped with atom interferometers, which use the wave character of atoms to measure the difference in phase between atomic matter waves along different paths. This technique will allow the spacecraft to detect the presence of non-gravitational noise (thruster activity, solar radiation pressure, thermal recoil forces, etc.) and negate them to the necessary degree. Meanwhile, flying in a tetrahedral formation will optimize the spacecraft’s ability to compare measurements.

“Laser ranging will offer us highly accurate data on the distances and relative velocities between spacecraft,” said Turyshev. “Furthermore, its exceptional precision will allow us to measure the rotation of a tetrahedron formation relative to an inertial reference frame (via Sagnac observables), a task unachievable by any other means. Consequently, this will establish a tetrahedral formation leveraging a suite of local measurements.”

Artist’s impression of the path of the star S2 as it passes very close to the supermassive black hole at the center of the Milky Way. Credit: ESO/M. Kornmesser

Ultimately, this mission will test GR on the smallest of scales, which has been sorely lacking to date. While scientists continue to probe the effect of gravitational fields on spacetime, these have been largely confined to using galaxies and galaxy clusters as lenses. Other instances include observations of compact objects (like white dwarf stars) and supermassive black holes (SMBH) like Sagittarius A* – which resides at the center of the Milky Way.

“We aim to enhance the precision of testing GR and alternative gravitational theories by more than five orders of magnitude. Beyond this primary objective, our mission has additional scientific goals, which we will detail in our subsequent paper. These include testing GR and other gravitational theories, detecting gravitational waves in the micro-Hertz range—a spectrum not reachable by existing or envisioned instruments— and exploring aspects of the solar system, such as the hypothetical Planet 9, among other endeavors.”

Further Reading: Physical Review D

The post Formation-Flying Spacecraft Could Probe the Solar System for New Physics appeared first on Universe Today.

The hatching of the 250th California condor chick at the San Diego Zoo marks a notable milestone for a species that narrowly evaded extinction

Everybody in the Biden administration is all juiced up to reward Hamas for attacking Israel by giving the Palestinians a state, one presumably run by the Palestinian Authority (PA).  People who make this suggestion, who include Biden and his running dog Anthony Blinken, seen to be ignorant of the fact that the PA is a terror-promoting organization that in some ways is even worse than Hamas, for it produces schoolbooks that have brought up generations of Palestinians to hate and want to kill Jews.

If you want to know why neither Hamas nor the PA (nor even a revised version of the PA) should be running Gaza and the West Bank after the war, read the Tablet piece below, which is reasonably short and full of facts. The author, Gaudi Taub, is also a broadcaster, a screenwritere, and a historian.  Click the headline; it’s a free read:

The title of the article is startling, but it is accurate. For the PA has placed a value on the stipend a terrorist will get depending on how many Jews he’s planned to hurt, actually hurt, or killed. And the more Jews you kill, the more money a jailed Palestinian gets, all through the “Martyr’s Fund” described in Wikipedia.  (It’s often called “pay-for-slay”.) I and others have talked about it before, yet many people still seem surprised that it exists. Not only that, but it’s funded in part by American taxpayers (via fungible money we give to NGOs, which becomes extra money for the PA), and, if the terrorist is killed (and becomes a martyr, or shahid), the terrorist’s family gets a stipend for life.

Now if anything is genocide, a program whereby Palestinians are financially rewarded for killing Jews is that.  Imagine if Jews got paid for each Palestinian they killed! The world would be outraged, and it would properly be called “genocide” (which Israel is not committing now).

The Martyr’s Fund takes up a huge portion of the PA;’s budget: about 7%, and according to Tablet ,the PA considers it the most important item in its budget, one that cannot ever be dispensed with. Below is a table of what dead Jews are worth to a jailed Palestinian; monthly stipends to prisoners (or their families) are calculated based on the time a terrorist is sentenced to jail.  (A New Israeli Shekel is worth 27¢ U.S, so divide by about four to get the monthly salary in dollars.

The PA, as I said, also creates and promotes terrorism through its schools, producing materials that are also used in UN (UNRWA) schools:.

Schools are a critical part of the socialization of Palestinian children into this culture. Not only do Palestinian school books contain direct incitement in the form of explicit murderous antisemitic ideology, but also every subject, including grammar and math, drills the same message into children’s brains. Take the following exam questions that Shemesh cites (p. 20):

“Hamas shoots a rocket which weighs 50 kilos in the direction of occupied Tel Rabia [Tel Aviv], which is 90.25 kilometers away. What speed does it need to fly, what would be the maximum height, and how long will it take it get there?”

Or:

“Two people are carrying on their shoulders a coffin weighing 200 Newton in the funeral of a martyr weighing 800 Newton.” The students are asked to calculate the strength the two men would need.

. . . . In other words, the cult of death reigns everywhere you turn. Regardless of how much well-meaning Israelis tried desperately to imagine otherwise over the years, the Palestinian national ethos is built around a genocidal war to ethnically cleanse Palestine, from the river to the sea, of Jewish presence.

Finally, the PA itself not only encourages terrorism, but also practices terrorism:

By now, moreover, we know that PA security forces personnel are directly involved in terror attacks. In fact, even as the press in Israel and in the West tries to ignore it, PA officials brag about their complicity in terrorism in Arabic to their own people. They cannot stand to lose their competition with Hamas in the national Jew-killing contest.

A Palestinian Media Watch report published in February, titled “Terrorists in Uniform,” quoted a PA spokesperson bragging that “roughly 63-65% of the number of Martyrs in the West Bank … are members of the Fatah Movement. And most of them are members of the [PA] Security Forces or their sons.” The police forces Israel armed and the U.S. military trains are active participants in the terror they were supposed to stop. Using the guns we gave them to stop terror, they instead kill Jews—in the process securing the livelihoods of their families.

There’s more, but just these three aspects of PA-induced terrorism should make Americans very wary of trying to have the organization help run a postwar government in Gaza—or any government ruling entities created in the now-impossible “two state solution. One of the morons who’s been roped into PA corral is Thomas Friedman of the NYT, who seems to have ignored this:

Regardless of this bloody track record, the White House and the State Department, along with pro-Democratic Party Israeli think tanks, former IDF generals nurtured on a woke ideological diet in American universities, and the Israeli press, are careful to maintain a conceptual barrier between Hamas as a terror organization, and the PA. The latter, they maintain, is a crucial partner in the fight against terrorism—the same PA that, in reality, glorifies and incentivizes terrorism.

The last sentence—the “solution” that Thomas Friedman, Biden, and Blinken love so much—is risible. No, the PA will never be “a crucial partner in the fight against terrorism”, for it is an explicit promoter of terrorism.  If you hear somebody touting the PA as a “nicer” version of Hamas, one that can work with America, remember the things above, especially the pay-for-slay program.

 

The Tablet article ends eloquently:

Less than two weeks after the Oct. 7 attack, the PA’s Ministry of Endowments and Religious Affairs included an infamous Hadith—a saying attributed in the tradition to the messenger of Islam—in its official guidelines that provided imams with talking points to use in their Oct. 20 Friday sermon in Palestinian mosques. The Hadith says that judgment day will only come after the believers have exterminated the Jews. On that day, it says, even rocks and trees will help in the cause of jihad. They will say, “Oh servant of Allah, there is a Jew hiding behind me; come and kill him.”

This horrific image, nature itself partaking in ridding the world of the unnatural Jewish scourge, is even more jarring against the backdrop of the Oct. 7 attack on the Nova nature festival, where partygoers attempted to hide behind rocks and bushes in the Negev desert to escape the slaughter.

The PA, the U.S. partner that Washington wants to put in charge of Gaza, has since added the families of the “martyrs,” the terrorists who were killed while committing the horrors of that terrible Shabbat morning, to the list of pay-for-slay beneficiaries.

Yes, the trees all say to come and kill the hiding Jews.

Most satellites share the same fate at the end of their lives. Their orbits decay, and eventually, they plunge through the atmosphere toward Earth. Most satellites are destroyed during their rapid descent, but not always

Heavy pieces of the satellite, like reaction wheels, can survive and strike the Earth. Engineers are trying to change that.

Satellite debris can strike Earth and is a potential hazard, though the chances of debris striking anything other than ocean or barren land are low. Expired satellites usually just re-enter the atmosphere and burn up. But there are a lot of satellites, and their number keeps growing.

In February 2024, the ESA’s European Remote Sensing 2 (ERS2) satellite fell to Earth. The ESA tracked the satellite and concluded that it posed no problem. “The odds of a piece of satellite falling on someone’s head is estimated at one in a billion,” ESA space debris system engineer Benjamin Bastida Virgili said.

That would be fine if ERS 2 was an isolated incident. But, according to the ESA, an object about as massive as ERS 2 reenters Earth’s atmosphere every one to two weeks. The statistics may show there’s no threat to people, but statistics are great until you’re one of them.

The ESA’s ERS-2 Earth observation satellite was destroyed when it re-entered Earth’s atmosphere on February 21st, 2004. Heavy parts of satellites, like reaction wheels, don’t always burn up in the atmosphere and can pose a hazard. ESA engineers are working on reaction wheels that will break into pieces to reduce the hazard. Image Credit: Fraunhofer FHR

The risk of being struck by chunks of a satellite isn’t zero. In 1997, a piece of mesh from a Delta II rocket struck someone’s shoulder in Oklahoma. It was a light piece of debris, so the person was okay. But it was an instructive event.

The heaviest parts of satellites, like reaction wheels, can be hazardous because they may not be destroyed during re-entry. Reaction wheels provide three-axis control for satellites without the need for rockets. They give satellites fine pointing accuracy and are useful for rotating satellites in very small amounts.

Reaction wheels can be quite massive. The Hubble Space Telescope has four reaction wheels weighing 45 kg (100 lbs) each. Other satellites don’t have such massive wheels, but the Hubble’s hefty wheels indicate the extent of the hazard. ESA engineers are designing reaction wheels that will break up during re-entry to reduce the hazard of one striking Earth.

“… the need is becoming urgent as more and more satellites are placed in space.”

Kobyé Bodjona, Mechanisms Engineer at the ESA

As part of the design process, they’re testing their wheels in a plasma wind tunnel at the University of Stuttgart Institute of Space Systems. The heated plasma in the tunnel moves at several km/sec, mimicking the friction a satellite is exposed to when it plunges through Earth’s atmosphere. The wheel is rotated inside the tunnel as if tumbling through the atmosphere.

At a recent Space Mechanisms Workshop at ESA’s ESTEC technical center in the Netherlands, engineers showed a clip of the blow-torch effect that the atmosphere has on falling debris.

“Space mechanisms cover everything that enables movement aboard a satellite, from deployment devices to reaction wheels,” explains workshop co-organizer Geert Smet.

“But these mechanisms often use materials such as steel or titanium that are more likely to survive reentry into the atmosphere. This is a problem because our current regulations say reentering satellites should present less than one in 10,000 risks of harming people or property on the ground or even one in 100 000 for large satellite constellations. ESA’s Clean Space group is reacting by D4D—devising methods to make total disintegration of a mission more likely, including mechanisms.”

The effort to make satellites disintegrate completely goes back a few years. The ESA program Design for Demise (D4D) is helping satellite manufacturers comply with the Space Debris Mitigation (SDM) requirements. It’s aimed at eliminating debris falling to Earth, removing debris already in orbit, and designing satellites that don’t linger in orbit after their missions have ended.

At the recent workshop, the ESA revealed more of its plans for active debris removal. There’s a push to develop dedicated spacecraft that can attach themselves to derelict satellites and force them into reentry. This will help remove dead satellites from the congested Low Earth Orbit.

“The idea behind this event is to present the mechanisms community with the latest research on space debris to see how they might contribute to the work going on,” said Kobyé Bodjona, Mechanisms Engineer at the ESA. “It’s important because large system integrators—the big companies that lead satellite projects—are going to need systems that are fully compliant with debris mitigation regulations. And the need is becoming urgent as more and more satellites are placed in space.”

The post Watch a Satellite Reaction Wheel Melt in a Simulated Orbital Re-Entry appeared first on Universe Today.

Bonobos have long been regarded as the peaceful ape, in sharp contrast with violent chimpanzees, but a study based on thousands of hours of observations suggests the real story is more nuanced

In 2022, astronomers discovered the brightest gamma-ray burst (GRB) of all time. Now, astronomers confirm that a 'normal' supernova, the telltale sign of a stellar collapse, accompanied the GRB. The team also looked for signatures of heavy elements like gold and platinum in the supernova. They found no evidence of such elements, deepening the mystery of their origins.

An international research team has for the first time directly detected stellar winds from three Sun-like stars by recording the X-ray emission from their astrospheres, and placed constraints on the mass loss rate of the stars via their stellar winds.

The rise of RNA viruses like SARS-CoV-2 highlights the need for new ways to fight them. RNA-targeting tools like CRISPR/Cas13 are powerful but inefficient in the cytoplasm of cells, where many RNA viruses replicate. Scientists have devised a solution: Cas13d-NCS. This new molecular tool allows CRISPR RNA molecules that are located within the nucleus of a cell to move to the cytoplasm, making it highly effective at neutralizing RNA viruses. This advancement opens doors for precision medicine and proactive viral defense strategies.

A star's magnetic field must be considered in order to correctly determine the characteristics of exoplanets from observations by space telescopes such as Kepler, James Webb, or PLATO. Researchers show that the distribution of the star's brightness over its disk depends on the star's level of magnetic activity. This, in turn, affects the signature of an exoplanet in observational data. The new model must be used in order to properly interpret the data from the latest generation of space telescopes pointed at distant worlds outside our Solar System.

There’s a good article in Quillette showing how one person, the notorious but (to me) highly admirable J. K. Rowling singlehandedly undercut Scotland’s new Hate Crime and Public Order Act that came into effect on April 1. I explained this law on March 27, also showing how the Scottish Police published as an example a woman named “Jo” (Rowling’s nickname) who said that people who didn’t identify as one of the two genders “should be put in the gas chambers.”  That is, of course, an oblique swipe at Rowling by the government, and I suspect she could have sued for defamation. But she got her revenge in another way.

Rowling has been attacked by gender activists for two of her stands: that trans women remain (biological) men (and vice versa), and that certain positions should be reserved for natal women, including participation in women’s sports, incarceration in women’s prisons, and rape and sexual-violence counseling.  I agree with both of these positions, and also with Rowling’s insistence that with these exceptions trans people should be treated with respect and dignity, and afforded all other rights.

That, of course, is not enough for gender activists, who have demonized Rowling as a transphobe. But she refuses to be demonized, and has fought back against her detractors as well as against the new law, which basically equates trans women with biological women in all respects, and also penalizes those who oppose this view.

Click below to read, and I’ll show how Rowling took down the law. She did it with tweets.

You can see the new law, which I’ll call the HCPOA, at the first link above. It’s basically a blasphemy law that wouldn’t stand in America since it violates the First Amendment guaranteeing free speech. Here’s how I described it before:

Note that it is a crime to make statements about age, disability, religious affiliation, sexual orientation, transgender identity, or “variation in sex characteristics”, stuff that a “reasonable person” would find “threatening”, “abusive”, and even “insulting”.  You don’t even have to have the intent of stirring up hatred.

Further, look at (2)aii above. You are committing a crime even if you “communicate to another person material that a reasonable person would consider to be threatening or abusive”.  So, for example, if you email a friend that a guy you don’t like “must have a small dick” (a common insult for males, but also abusive because it makes fun of “variation in a sex characteristic”), or say to someone “Jack is a dotty old codger”, which insults someone on the grounds of age, then those might be offenses.

Also, as one reader said, “Part of the reason why people are so worried is that the guidance that Police Scotland have issued seems to be somewhat different from what the law itself says. It’s a download document 29 pages long.”  Looking at it briefly, I find two things extra worrying.

First, even if what you do doesn’t amount to a “crime,” it’s supposed to be reported and the coppers will investigate it, probably putting your name on the record,

Indeed, they DO put your name on the record, even if you haven’t violated the law. And employers and others can get access to your record. Note too that women are not included in the protected class, so you can spew all the misogyny you want. Here’s one example from the article:

Most of us wouldn’t regard mocking someone’s “non-binary” identity as deserving of a “hate incident” marker, but that’s what happened to a Conservative MSP, Murdo Fraser, after he shared a post on X ridiculing the Scottish government’s “non-binary action plan.” Every “community” has to have its own action plan these days, leading to a proliferation of oppressed groups with confusingly similar titles. “Choosing to identify as ‘non-binary’ is as valid as choosing to identify as a cat,” Fraser wrote. “I’m not sure Governments should be spending time on action plans for either.”

He was aghast when he discovered that Police Scotland had logged an NCHI on his record for this joke, but hadn’t done the same in relation to the complaints against Rowling and Yousaf. He accused the force of “double standards” while SNP MP Joanna Cherry, a rare sensible voice within the party, suggested that senior officers were revising policy “on the hoof” to avoid the embarrassment of recording an NCHI against an internationally famous author. (This sequence of events became even more absurd when the force suddenly changed its tune, telling Fraser his personal details hadn’t been logged in relation to an NCHI after all.)

Further, application of this law is subjective, particularly because the determination of “hate” depends not at all on the violator’s intention, but on the subject’s interpretation of the violator’s motivation. It is, in other words, an “I’m offended” law.

That’s insane. As you might expect, the Scottish coppers are being flooded with complaints, many of them probably designed to undercut the law. They’re coming in at the rate of one per minute, and the cops are complaining that investigating every report (which they must do) distracts them from investigating more serious crimes. Finally, if you don’t want to deal directly with the cops when reporting an offense, the government has designated some weird “third party reporting centres” where you can register your offense. These include a sex shop (!) and a salmon and trout farm, presumably where you can buy some lox without being doxed.

Enter Rowling, my hero. She simply issued a series of tweets, the last one of which completely undermined the law by demanding that if anybody is arrested for misgendering (e.g., “going after a woman for calling a man a man”) she would simply repeat what got the person arrested so Rowling could be charged, too. And of course the Scottish police are not going to charge J. K. Rowling!

To show her devastating attack, delivered with with and humor, I’ll show all of Rowling’s tweets, as some will make sane people laugh.

First, her pinned tweet laying out her views. It’s long and you can click on it to read the whole thing, but note that she starts with the biological definition of the (two) sexes:

I believe a woman is a human being who belongs to the sex class that produces large gametes. It’s irrelevant whether or not her gametes have ever been fertilised, whether or not she’s carried a baby to term, irrelevant if she was born with a rare difference of sexual development that makes neither of the above possible, or if she’s aged beyond being able to produce viable eggs. She is a woman and just as much a woman as the others.

You’ve asked me several questions on this thread and accused me of avoiding answering, so here goes.

I believe a woman is a human being who belongs to the sex class that produces large gametes. It’s irrelevant whether or not her gametes have ever been fertilised, whether or not… pic.twitter.com/X6mbdJ0YVm

— J.K. Rowling (@jk_rowling) April 6, 2024

And then the devastating series of ten tweets followed by her admission that she was “just kidding”, and then her big challenge to the legal system..

Lovely Scottish lass and convicted double rapist Isla Bryson found her true authentic female self shortly before she was due to be sentenced. Misgendering is hate, so respect Isla’s pronouns, please. Love the leggings! 2/11 pic.twitter.com/aKgOWRdb4K

— J.K. Rowling (@jk_rowling) April 1, 2024

“Love the leggings!” LOL.

Samantha Norris was cleared of exposing her penis to two 11-year-old girls. Hooray! Unfortunately she was then convicted for possession of 16,000 images of children being raped and sexually assaulted. Be that as it may, Sam’s still a lady to me! 4/11 pic.twitter.com/GG2kLql3Ea

— J.K. Rowling (@jk_rowling) April 1, 2024

But most women aren’t axe-toters or sex offenders, so let’s talk role models! Guilia Valentino (in red) wanted to play on the women's team 'because of sisterhood, validation and political visibility'. Naturally, she was given some boring cis girl’s place. Yay for inclusion! 6/11 pic.twitter.com/zl5i41RqBG

— J.K. Rowling (@jk_rowling) April 1, 2024

Munroe Bergdorf isn’t just a pretty face! Public campaigner for a children’s charity until safeguarding concerns were raised, she was appointed UN Women’s first ever UK champion. ‘What makes a woman “a woman” has no definitive answer,’ says Munroe. Great choice, UN Women! 8/11 pic.twitter.com/za6GG5q2Oo

— J.K. Rowling (@jk_rowling) April 1, 2024

Last, but least, TV’s India Willoughby proves we women can call a black broadcaster a ‘nasty bitch’ who ‘wouldn’t be anywhere without woke’, dub lesbians men, insult the looks of a female Olympic swimmer, ‘joke’ about kidnapping feminists, and STILL get airtime! What a gal! 10/11 pic.twitter.com/gShqbEvO5s

— J.K. Rowling (@jk_rowling) April 1, 2024

The last tweet is her admission that she’s violated the HCPOA. Click screenshot to read the whole thing.

And, at the end:

It is impossible to accurately describe or tackle the reality of violence and sexual violence committed against women and girls, or address the current assault on women’s and girls’ rights, unless we are allowed to call a man a man. Freedom of speech and belief are at an end in Scotland if the accurate description of biological sex is deemed criminal. I’m currently out of the country, but if what I’ve written here qualifies as an offence under the terms of the new act, I look forward to being arrested when I return to the birthplace of the Scottish Enlightenment. If you agree with the views set out in this tweet, please retweet it.

Yes, ma’am:

Retweeted per JKR's request: "if what I've written here qualifies as an offence under the terms of the new act, I look forward to being arrested when I return to the birthplace of the Scottish Enlightenment. If you agree with the views set out in this tweet, please retweet it." https://t.co/kY4dmB8XXT

— Jerry Coyne (@Evolutionistrue) April 12, 2024

The ten tweets above, with the eleventh as a finale, is one of the great takedowns of virtue-signaling activism of our era, featuring transwomen who, says Rowling, are “men, every last one of them.” Clearly an offense!

But the cherry atop this Cake of Snark is this:

If they go after any woman for simply calling a man a man, I'll repeat that woman's words and they can charge us both at once. pic.twitter.com/s9OcsgHr5j

— J.K. Rowling (@jk_rowling) April 2, 2024

As Quillette noted, “Feminists hailed the novelist as a heroine, understanding that she had thrown the protection provided by her wealth and status over thousands of other women.”  And don’t you doubt that if anybody is charged for a hate crime by calling a transgender woman a “man”, Rowling will simply repeat it. The cops would have to charge Rowling, too, and what are they chances they’d do that?

The new law, as an “I’m offended” blasphemy law, is unnecessary, unworkable, and impossible to apply.  It is not needed and should be repealed.  I have no idea what brought this dumb law onto the books, but Quillette hazards a guess, involving the Scottish drive for independence from Britain:

The ruling Scottish Nationalist Party (SNP) lost a crucial referendum in 2014, failing to persuade enough Scots to vote in favour of independence, and it has seemed rudderless ever since. Much of what has happened in Scotland in the last decade can be traced back to that crushing disappointment, as the SNP struggled to establish its purpose and identity. In an irony that’s hard to miss, a party built on the supposedly indelible differences between the English and Scottish has sought to solve its problem by embracing a faddish ideology, transgenderism, which proposes that anyone can be whatever they like. And that includes an apparently unshakable conviction that men can become women and vice versa.

Indeed identity politics has become as central to the SNP’s creed, if not more so, than taking Scotland out of the UK. In a reversal of Whisky Galore-type stereotypes, in fact, the Scots have now taken on the role of witch-finders, sniffing out heretical thoughts under the cover of a supposedly liberal ideology. A vast amount of parliamentary time has been wasted on bad and unnecessary legislation advocated by trans activists, including a bill to remove all safeguards from the process that allows people to change their legal gender. The UK government salvaged the day by blocking the reckless Gender Recognition Reform Act last year, but the SNP had another trick up its sleeve.

The Hate Crime and Public Order (Scotland) Act came into effect on April 1—April Fools’ day, as critics were quick to point out. It’s been on the statute books since 2021, but implementation was delayed because no one could say with any certainty what it actually criminalised.

Well, who knows? But I do know that J. K. Rowling, despite her fame and wealth, has risked something more valuable—her reputation—by standing up for her principles.

An Arctic-wide survey has found that the permafrost region is emitting more carbon into the atmosphere than it absorbs, causing the planet to heat even further

Although the elimination of SATs or other standardized tests during the Pandemic Era (or giving students the option of submitting them) was justified by various excuses about viruses and so on, in most cases the real reason was to create equity.  Especially when it became clear that the Supreme Court would declare race-based admission illegal, colleges eliminated standardized tests as a way to achieve racial equity, assuming that the lower average scores of minorities would translate into lower admissions.  And yet several studies have shown that standardized tests are the best predictor of college grades (“success”).

But it didn’t quite work that way. At least under the “test optional” criterion, a study by Dartmouth College showed that the “optional” criterion used by many schools had the effect of harming admissions prospects of lower-income students, since they often thought, mistakenly, that their test scores would hurt them. Here’s a bit from a NYT article by David Leonhardt that I wrote about in February:

Last summer, Sian Beilock — a cognitive scientist who had previously run Barnard College in New York — became the president of Dartmouth. After arriving, she asked a few Dartmouth professors to do an internal study on standardized tests. Like many other colleges during the Covid pandemic, Dartmouth dropped its requirement that applicants submit an SAT or ACT score. [JAC: Four-part ACTs are alternatives to SATs.] With the pandemic over and students again able to take the tests, Dartmouth’s admissions team was thinking about reinstating the requirement. Beilock wanted to know what the evidence showed.

“Our business is looking at data and research and understanding the implications it has,” she told me.

Three Dartmouth economists and a sociologist then dug into the numbers. One of their main findings did not surprise them: Test scores were a better predictor than high school grades — or student essays and teacher recommendations — of how well students would fare at Dartmouth. The evidence of this relationship is large and growing, as I explained in a recent Times article.

A second finding was more surprising. During the pandemic, Dartmouth switched to a test-optional policy, in which applicants could choose whether to submit their SAT and ACT scores. And this policy was harming lower-income applicants in a specific way.

The researchers were able to analyze the test scores even of students who had not submitted them to Dartmouth. (Colleges can see the scores after the admissions process is finished.) Many lower-income students, it turned out, had made a strategic mistake.

They withheld test scores that would have helped them get into Dartmouth. They wrongly believed that their scores were too low, when in truth the admissions office would have judged the scores to be a sign that students had overcome a difficult environment and could thrive at Dartmouth.

After this study, Dartmouth reinstated the SAT test as a mandatory requirement for applicants,

Now Harvard University (which as students we called “Schmarvard”), has also reinstated mandatory standardized tests as part of the admissions process.  Click to read:

This is from the April 11 Harvard Magazine:

Harvard announced today that the College will reinstitute mandatory submission of standardized test scores for applicants, beginning with students applying for fall 2025 admission (the class of 2029). Until today’s decision, the College had a test-optional policy in place for applicants through the class of 2030. The announcement follows similar decisions by Dartmouth, Yale, and Brown to require standardized testing beginning with the class of 2029.

Test-optional policies were widely adopted during the pandemic, when it was difficult to sit for standardized tests, and many remained in place even as the threat of illness faded. The tests were thought to disadvantage lower-income students and those from under-resourced high schools. But a working paper coauthored in 2023 by Ackman professor of public economics Raj Chetty, Black professor of political economy and professor of education and economics David Deming, and John Friedman, a professor of economics at Brown, found standardized tests are a useful means of identifying promising students at less well-resourced high schools. In a statement, Chetty said “Critics correctly note that standardized tests are not an unbiased measure of students’ qualifications, as students from higher-income families often have greater access to test prep and other resources. But the data reveal that other measures—recommendation letters, extracurriculars, essays—are even more prone to such biases. Considering standardized test scores is likely to make the admissions process at Harvard more meritocratic while increasing socioeconomic diversity.”

As previously reported, MIT, which reinstituted a testing requirement last year—citing SAT math scores as measures of an applicant’s ability to handle a highly quantitative curriculum—recently reported enrolling its most diverse class. (In late March, Emi Nietfeld’15 hadargued in favor of mandatory standardized testing from the perspective of a disadvantaged applicant in this New York Times essay, “How the SAT Changed My Life.”)

In today’s announcement, Harvard said it will require submission of SAT or ACT scores, but that other eligible tests, such as AP exams and International Baccalaureate scores, will be accepted in exceptional cases.

The Dean of the Faculty of Arts and Science parroted the Dartmouth finding:

“Standardized tests are a means for all students, regardless of their background and life experience, to provide information that is predictive of success in college and beyond” said Faculty of Arts and Sciences Dean Hopi Hoekstra in an email to students and colleagues. “Indeed, when students have the option of not submitting their test scores, they may choose to withhold information that, when interpreted by the admissions committee in the context of the local norms of their school, could have potentially helped their application. In short,” she continued, “more information, especially such strongly predictive information, is valuable for identifying talent from across the socioeconomic range.”

It’s about time. And notice that what’s mentioned is “across the socioeconomic range” rather than “across the ethnic range.”  I don’t know if “socioeconomic” is the new code word for “race,” but the mandatory submission of test scores can only be a good thing. How can it hurt? It’s a way of identifying talent that isn’t revealed by high-school grades or where someone went to high school, and if a college wants to admit students on the basis of either merit or likelihood of success (they’re correlated), the make the tests obligatory.

Well, I have about three batches of photos left, so by Monday we’ll be kaput. I’m very sad that readers aren’t stepping up, but this seems to be part of the senescence of this website.

Here’s a third batch (of three) by reader Ephraim Heller taken in the Galápagos (#1 is here and #2 is here).  More birds today, and you can enlarge the photos by clicking on them. Captions and IDs by Ephraim. and I request readers’ help with those species that aren’t identified.

One of the 18 species of Galápagos finches studied by Darwin [JAC: readers’ IDs welcome]

Galápagos flycatcher (Myiarchus magnirostris) . Another common endemic species.

American flamingo (Phoenicopterus ruber):

Unidentified bird collecting nesting material:

Great blue heron (Ardea herodias) consenting to a close up shot.

Self-explanatory photos of swallow-tailed gulls (Creagrus furcatus):

Nazca booby (Sula granti). Per Wikipedia: Siblicide has been well studied in this species; the first chick is born around five days before the second and is larger and stronger by the time the second is born. It drags its younger sibling out of the nest. Field experiments in the Galapagos demonstrated that the boobies can manage to feed two chicks without too much difficulty. This raises questions as to the origin of the phenomenon. Nazca booby regurgitating food for its chick (who has presumably murdered its sibling):

The particle physics community is mourning the passing of Peter Higgs, the influential theoretical physicist and 2013 Nobel Prize laureate. Higgs actually wrote very few papers in his career, but he made them count.

It’s widely known that Higgs deeply disapproved of the term “God Particle”. That’s the nickname that has been given to the type of particle (the “Higgs boson”) whose existence he proposed. But what’s not as widely appreciated is why he disliked it, as do most other scientists I know.

It’s true that Higgs himself was an atheist. Still, no matter what your views on such subjects, it might bother you that the notion of a “God Particle” emerged neither from science nor from religion, and could easily be viewed as disrespectful to both of them. Instead, it arose out of marketing and advertising in the publishing industry, and it survives due to another industry: the news media.

But there’s something else more profound — something quite sad, really. The nickname puts the emphasis entirely in the wrong place. It largely obscures what Higgs (and his colleagues/competitors) actually accomplished, and why they are famous among scientists.

Let me ask you this. Imagine a type of particle that

• once created, vanishes in a billionth of a trillionth of a second,
• is not found naturally on Earth, nor anywhere in the universe for billions of years,
• has no influence on daily life — in fact it has never had any direct impact on the human species — and
• only was discovered when humans started making examples artificially.

This doesn’t seem very God-like to me. What do you think?

Perhaps this does seem spiritual or divine to you, and in that case, by all means call the “Higgs boson” the “God Particle”. But otherwise, you might want to consider alternatives.

For most humans, and even for most professional physicists, the only importance of the Higgs boson is this: it gives us insight into the Higgs field. This field

• exists everywhere, including within the Earth and within every human body,
• has existed throughout the history of the known universe,
• has been reliably constant and steady since the earliest moments of the Big Bang, and
• is crucial for the existence of atoms, and therefore for the existence of Earth and all its life;

It may even be capable of bringing about the universe’s destruction, someday in the distant future. So if you’re going to assign some divinity to Higgs’ insights, this is really where it belongs.

In short, what’s truly consequential in Higgs’ work (and that of others who had the same basic idea: Robert Brout and Francois Englert, and Gerald Guralnik, C. Richard Hagen and Tom Kibble) is the Higgs field. Your life depends upon the existence and stability of this field. The discovery in 2012 of the Higgs boson was important because it proved that the Higgs field really exists in nature. Study of this type of particle continues at the Large Hadron Collider, not because we are fascinated by the particle per se, but because measuring its properties is the most effective way for us to learn more about the all-important Higgs field.

Professor Higgs helped reveal one of the universe’s great secrets, and we owe him a great deal. I personally feel that we would honor his legacy, in a way that would have pleased him, through better explanations of what he achieved — ones that clarify how he earned a place in scientists’ Hall of Fame for eternity.

Live from Dallas with special guest Dustin Bates of Starset; Eclipse Science; News Items: AI Designed Drugs, AI Music, Music Getting Simpler, Aphantasia Spectrum, Nova and Comet Compete with Eclipse; Science or Fiction

After a short conversation with an artificial intelligence, people’s belief in a conspiracy theory dropped by about 20 per cent

Five years ago, a fossil found in the Philippines was determined to be from a new species of hominin called Homo luzonensis. Since then, we’ve learned a bit more about the newest member of the human family

A new study designed to better account for hidden confounding factors has found no link between acetaminophen use during pregnancy and the risk of neurodevelopmental conditions in childhood.

The post New Study Finds No Link Between Autism and Acetaminophen Use During Pregnancy first appeared on Science-Based Medicine.

Exploration of the Moon or other dusty environments comes with challenges. The lunar surface is covered in material known as regolith and its a jaggy, glassy material. It can cause wear and tear on equipment and can pose a health risk to astronauts too. Astronauts travelling to Mars would experience dust saucing to everything, including solar panels leading to decrease in power. To combat the problems created by dust, NASA is working on an innovative electrodynamic dust shield to remove dust and protect surfaces from solar panels to space suits. 

Dust is common on Earth as much as it is on other worlds although of course the source can be very different. It plagues are homes and leads to the constant battle to remove it from our homes in the almost ritualistic activity of dusting. Even here there are a multitude of sprays, brushes and rags that claim to help. Some even employ the electrostatic force to help repel dust from surfaces. It is a mere annoyance to us, perhaps causing the odd electrical device to over heat but largely its a small part of our lives. On alien worlds, it can lead to serious equipment malfunction and serious health hazards. 

Researchers at NASAs Kennedy Space Centre in Florida are now turning to electrostatic forces for help to keep astronauts and equipment dust free. Technology is being developed that has been called the Electrodynamic Dust Shield (EDS) –  I rather wish they dropped the word dust from the title to make it sound a little more StarTrek! The shield uses transparent electrodes and electric fields to electrically remove dust from surfaces.The idea was inspired by the electric curtain concept that was developed by NASA in 1967 but this new EDS has been in development since 2004. 

A close-up view of astronaut Buzz Aldrin’s bootprint in the lunar soil, photographed with the 70mm lunar surface camera during Apollo 11’s sojourn on the moon. Image by NASA

Dust exposure is a real concern for Commercial Lunar Payload Services and Artemis missions as the material can get into gaskets and seals, hatches and even potentially lunar habitats compromising their integrity. Dr Charles Buhler, lead scientist said “For these CPLS and Artemis missions, dust exposure is a concern because the lunar surface is far different than what we’re used to here.”

It’s the nature of the stuff to, not just that it gets everywhere like sand after a day at the beach. It is really abrasive like tiny pieces of glass because, unlike Earth where weathering tends to dull sharp edges, no such process occurs on the Moon. Even brushing the stuff off surfaces can lead to problems. 

The technology has been tested in vacuum chambers to simulate the space environment and results looked very promising. The Apollo missions collected samples of lunar regolith and some of this was used in the testing. The material was ejected from the surface within seconds. Following the successful tests, EDS materials were embedded on glass panels and test spacesuit fabrics on board the International Space Station and more recently Intuitive Machines first lunar lander too. EDS technology was used in lenses in the EagleCam CubeSat camera. Data is now being collected and future missions will carry the EDS concept to further test its capability to keep machines and humans safe on dusty worlds. 

Source : NASA Technology Helps Guard Against Lunar Dust

The post NASA is Building an Electrodynamic Shield to Deal with all that Dust on the Moon and Mars appeared first on Universe Today.