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I’ve finally left the entrance to Hell, otherwise known as Las Vegas. Thank goodness the conference was there to provide respite from the noisy, jangling streets, filled with tattooed people swilling margaritas. But of course all I know of Vegas is the Strip, and I’m told there are parts of the city that resemble real urbanity.  So be it.

A few photos and a video from my stay:

The Bacchanal Buffet at Caesar’s Palace. For a mere $85 you get 90 minutes to stuff your gut with as much food as you can. And it’s good food, by and large, so I’d say the buffet is worth it. Given how fast i.5 hours pass, I didn’t have the time to photograph much of the food. This is the beginning of the carving station (the buffet is HUGE). The lamb t-bones, at lower right, are small cuts of lamb that were absolutely terrific (Mike Chen recommended them on his Bacchanal Buffet video).

Below: the beginning of the seafood station. My buffet strategy was to first eat crustaceans and oysters (crab claws, snow crab legs, oysters Rockefeller), and then head for the meats (prime rib and lamb), have an elote (Mexican ear of corn), and then fill in the remaining gastric corners with desserts. I believe I got my money’s worth. Here’s a man grabbing crab.

If you go (and you have to go to a buffet in Vegas), I’d recommend this one, but watch a few videos on YouTube about the offerings, which will help you plan your buffet strategy. 90 minutes go by awfully quick!

Caesar’s Palace is the height of kitsch, decorated with Greek and Roman statuses throughout. Here’s one with a statue next to an ATM:

Back the the Horseshoe, feeling like a python that’s ingested a small antelope.  These are scenes from the casino floor at the Horseshoe, where we were staying and the site of CSICon.

Slot machines are everywhere, and they are no longer one-armed bandits, but are designed to appeal to the video-game generation. They are loud and big, liable to set off epileptic fits in those susceptible to their flashing lights. Plus you’re allowed to smoke on the casino floor, so it doesn’t smell all that great.

The lacunae between machines are filled with craps, roulette, or blackjack tables. Here’s a craps table for betting on dice:

Lots of action around the tables:

I found a cat-themed slot machine called “Karma Kat”!

. . . and here is a short video I took of what it’s like on the casino floor. Even when it’s not busy, as below, it’s noisy. Look at all those slots!

My friend Phil Ward, an entomologist at UC Davis, picked me up at noon for the two-hour drive to his shared house in Ivins, Utah, near St. George. We went through a bit of Arizona and then entered Utah, where I’m staying for the next three days, planning trips to the National Parks like Bryce and Zion—places I’ve never been.

First, though, we passed through an Indian reservation (“Native American” reservation?), housing what is formally known as the Shivwits Band of Paiutes, who settled in the area around 1100 B.C. and were hunter-gatherers but also cultivated crops. The only members of the tribe I saw were at the gas station/convenience store, whose sign is below.

It immediately struck me that “Shivwits” sounds like a Jewish name, and it went through my head that this might be one of the lost tribes of Israel that settled in Utah. (Remember, Mormons believed that Jesus came to America.) And then a joke went through my head if that scenario were true: A Shivwitz male could say, “I am a Man of Shivwitz.” Get it? Of course I mean no disrespect to the tribe; it’s just wordplay.

Gas was about as cheap as I’ve ever seen here: about 3 bucks a gallon (I believe things sold on Native American reservations are exempt from tax), so we filled up for the trip to Zion today. Proof:

Ivins is small and inconspiculous, with houses built only one story high and deigned to blend into the mountain scenery. It is beautiful here. Below is the view from my bedroom window (the house belongs to four people: Phil and three of his friends):

Today we head for Zion National Park, a place I’ve always wanted to visit because of its geological beauty. I’m bringing my decent point-and-shoot Panasonic Camera and will post pictures. Here’s one from the Wikipedia site, labeled “Zion Canyon at sunset in Zion National Park as seen from Angels Landing looking south.”

Diliff, CC BY-SA 3.0, via Wikimedia Commons

Recently a reader, having read my post about why the speed of light seems so fast, sent me two questions that highlight important cosmic issues.

1. Is there in fact anything within physics as it’s presently understood that indeed prevents […] there existing something other than atoms as some basic “unit”?
   
2. I’ve long wondered why it is that despite the seeming brilliance of humans at building such complex understanding, we are still pushing at such limits as the time it would take to fly a space ship to another galaxy. Is it really true that nothing could ever exceed ‘c’ and thus we are indeed doomed to take lifetimes to travel beyond our solar system? Or is it because we have not yet discovered something much more fundamental about the universe, such as an ‘alternative to’ the atom?

These deep questions are examples of an even broader pair of questions about reality.

• Which aspects of the cosmos are contingent?—in that one could easily imagine a similar universe in which these details are thoroughly altered.
• Which aspects of the cosmos appear rock solid?—in that they are so deeply integrated into the universe that it is difficult to imagine changing them without ruining everything.

Could something other than atoms serve as a basic material unit?

The answer to this question is “absolutely yes.”

If we look at the composite objects that make up ordinary matter, we are looking at specific particles and specific forces. There are four levels of composite objects:

• protons and neutrons made from quarks and gluons via the strong nuclear force
• atomic nuclei made from protons and neutrons via the residual strong nuclear force
• atoms made from nuclei and electrons via the electromagnetic force
• molecules made from atoms via the (often residual) electromagnetic force

But the details are complex and have to do with the precise natures of the particles and the forces. A universe with different particles and/or different forces might make entirely unfamiliar composite objects—or none at all.

Here’s where the power of theoretical physics shows itself. We can in some cases calculate what would happen in an imaginary universe with its own types of particles and forces, and gain some insights into the composite objects that might result. More challenging is to figure out whether some macroscopic material, analogous to the ordinary large-scale solids and fluids we’re familiar with, could exist in that universe. But it’s easy to show that many types of composite objects could potentially exist in other, imaginary universes, and though different from our familiar atoms, they could nevertheless serve as building blocks for complex materials.

How about in our own, real universe? There’s still a lot we don’t know about it. Experiments leave open the possibility that there are types of particles that we haven’t yet discovered, perhaps entire classes of them. There are two reasons we might not have found them.

• Too Much Mass: If a particle’s mass is very large (roughly a thousand times the mass of a typical atom, or more), then we can’t make it directly in our particle accelerators; and if such particles are also rare in the universe, with very few of them surviving from the Big Bang, then we would neither find them on purpose nor by accident. They might form unknown forms of composite objects, through either known or unknown forces.
• Too Hidden: If a type of particle is insensitive to the known types of forces (excepting gravity), then our experiments would neither detect their presence nor be able to produce them directly. Such particles are referred to as “hidden” or “dark”. They might even make up dark matter, giving us a hint of their existence through their gravity, but no other direct information that would help us learn their details. If they interact with each other via their own set of forces, those forces might allow them to make unknown and hidden composite objects.

For some types of particles, both of these reasons could simultaneously be true.

Composite objects formed by these unknown particles, through known or unknown forces, could potentially be as complex and variegated as atoms. As an example, researchers have taken seriously the possibility that dark matter is made from some sort of exotic atom, formed from dark elementary particles and forces, and asked about the particle physics and astrophysics consequences. (Here’s one paper on the subject; here’s another more recent one.)

And so, both theoretical considerations and existing experiments allow for the possibility of an unknown material made from unknown basic building blocks or units. This is true both in the abstract, where we imagine other possible universes, and in the concrete, in that it may even be true in our own universe. It may be that dark matter, or some other substance as yet unknown, has this property.

Can the speed of light be exceeded?

Before answering this, one must state carefully what one means by this question; I have pointed out pitfalls here. The proper form of the question is:

• When two objects pass each other, could an observer traveling with one object find that the speed of the second object is higher than the cosmic speed limit?

(If you ask the question in the wrong way — for instance, if you ask, can I observe two objects whose relative motion is faster than the speed of light from my point of view? — then the answer is “yes, and it happens all the time; just look at two oppositely-directed flashlight beams, or, as viewed from the laboratory, the two proton beams in the Large Hadron Collider.” Clearly that’s not what the reader is asking.)

In any universe in which Einstein’s view of gravity (known as general relativity) is true, for which local processes are described by special relativity, taught in first-year physics classes, the answer would be firmly “no.” In such a universe, there is a unique, unbreakable cosmic speed limit that applies to all objects equally. The very nature of space and time prevent anything from breaking it.

For example, if you tried to overtake a light beam, you’d find that the faster you go, the faster the light would seem to go, too, making it impossible for you to catch up to it. (In my book, I called this the “nightmare property” of the universe, since it sounds uncannily like a certain type of bad dream.) No matter what you do to improve your chances, your experience of time and space will adjust in such a way that your efforts will fail. It’s not a matter of better technology. Even infinitely powerful technology cannot beat the universe’s basic structure.

It is widely believed that, in our universe, Einstein’s general relativity is correct to a very good approximation. It can’t be exactly correct, because it doesn’t meld well with quantum physics, which we know is another feature of our universe. When quantum physics meets space and time, it might not even be meaningful to define “speed”, at least not in a straightforward way. So there might be circumstances in which the cosmic speed limit does not apply in the ways we are used to.

However, it seems to me profoundly unlikely that any violation of the cosmic speed limit, induced perhaps by quantum physics, will permit humans to travel faster than light. We ourselves are creatures of ordinary space and time, and in any situation in which space and time behave in an extraordinary way, or in which we try to move across it an extraordinary way, would probably kill us. (I’ve just finished reminding you how fragile we are and why this means that we must travel slowly relative to our surroundings. As another unrelated but amusing example of this point, see section 3.4 of this paper, a light-hearted yet scientifically rigorous look at just how difficult it would be to make wormholes that humans or spacecraft could safely cross through.)

Even if you just wanted to send a message faster than light, you would presumably still want to be sending it across normally-defined space and time. The structure of the cosmos would likely ensure that you would fail.

This is not to say that we should be closed-minded about this question. Sometimes our understanding of the universe takes a strange twist, and there’s a lot about space and time that we don’t yet understand. But being open-minded is not the same as being empty-headed. Any chance of violating this basic cosmic constraint on space-time, at least in any way that would affect our ability to cross the cosmos, currently seems like a very, very long shot.

One more point: could there be imaginary universes with no cosmic speed limit at all? Maybe. But in such a universe, extremely distant events in the universe could potentially have an instantaneous impact on our lives. Cause and effect might be harder to understand, and it’s not clear (to me, anyway) that such a universe would function well.

Final cosmic thoughts about speed and time

The bottom line:

1. No principle or experiment forbids the existence of unknown materials made from unknown basic objects, much as familiar matter is made from atoms.
2. The existence of a cosmic speed limit seems to be a basic structural element of the universe; this statement is suggested by theoretical principles and has a solid experimental basis (see for instance this recent paper).

So it turns out, though this would hardly have been obvious a century ago, that it’s much easier to imagine replacing atoms with something else than to evade the cosmic speed limit.

As a last thought, let me add something regarding this part of the reader’s second question:

• Is it really true that nothing could ever exceed ‘c’ and thus we are indeed doomed to take lifetimes to travel beyond our solar system?

“Yes” for the first half of the question; but “no” (in a sense) for the second.

Even though nothing can exceed the cosmic limit under any familiar circumstances, it is still true that time can play tricks, as it behaves unexpectedly in our universe. It is possible in principle (though probably impossible practically, due to the difficulty of building suitably safe rockets) for you to travel to many stars, even all across our entire galaxy, in your lifetime. Unfortunately, for those left behind on Earth, your trip will take far longer than their lifetimes.

This is sometimes called the “twin paradox” (and it underlies the emotional plot of the movie Interstellar) but there’s nothing paradoxical about it. It’s just unfamiliar. It rests on a basic fact: the amount of time that you measure between one event and another depends on the nature of the journey that you took to get from the initial event to the final one.

Said another way: time is something experienced by each object separately, as measured by a clock carried along with that object, and it depends on how the object moves around within the universe. There is no universal clock that exists across the universe, and outside individual observers and objects, that can measure some universal notion of time.

Specifically, the amount of time that elapses for someone traveling far from Earth to distant stars and then returning home can be far less than the amount of time that elapses meanwhile on Earth. This is not an illusion or a trick; it’s just a fact about time that’s not at all obvious from daily life. The consequence is that you yourself could visit many stars, but your friends or family (and multiple generations after them) would be long dead when your rocket landed back on Earthly soil.

(Note: In a perfectly smooth and uniform universe, there would be some reasonable notion of “universal time”; and since our universe is approximately uniform on very large distance scales, there is an approximate notion of universal time, which is quite similar to Earth time, that is useful on very large distance scales. That’s why we can talk about “the time since the Big Bang”, using this approximate universal time, and say that the universe is 13.8 billion years old; it’s approximately true for observers and objects that have not moved rapidly relative to the average objects in the universe, such as typical galaxies and our own planet. But this universal time does not apply to, say, individual observers taking extremely rapid, complex round trips around the galaxy. Such observers may live far longer than 100 years of approximate universal time — though for each of them, life will feel just as long as it does for us, because the rate of their thinking, breathing and metabolism relative to the time they experience is the same as it is for any human. Again, see the movie Interstellar for illustrations of this effect.)

Single-celled organisms called archaea can become multicellular when compressed, highlighting the role of physical forces in evolution

This idea really is quite a fascinating one. Currently a trip to Mars would require large amounts of air, water and other resources to sustain human life but would also expose travellers to harmful levels of radiation. A wonderful solution has been proposed in a new paper recently published by researchers from Ukraine. They propose that asteroids which already travel relatively close by Earth, Mars and even Venus already could be used to hop between the planets. They are already making the journey anyway and so perhaps the cosmos already provides the solution to interplanetary travel. 

After a return to the Moon, the red planet Mars is next on the list for human exploration. On average it is 225 million km away so a round trip would require astronauts to be away from home for about 3 years! Spending this length of time in space raises a number of serious health risks many of which are caused by prolonged exposure to radiation and microgravity. Over time, muscles and bone density will decline so that the skeletal part of the body will no longer bear enough weight to sustain a return to Earth’s gravity. The cardiovascular system would adjust to microgravity too making heart issues likely upon return. There would be an increased risk of cancer and damage to the nervous system as a result of the prolonged exposure to radiation. The list goes on! 

Mars, Credit NASA

The paper recently authored by A. S. Kasianchuk and V.M. Reshetnyk from the National University of Kyiv in Ukraine they report upon their analysis of the orbit of more than 35,000 near-Earth asteroids. They have been looking for the possibility of successive approaches to all pairs of planets Earth – Venus and Earth – Mars within a time range of 2020 to 2120. If successive passes exist then why not, the team suggest, use the asteroids as interplanetary busses to provide a fast transfer between the planets, possibly even as fast as 180 days. 120 candidates were discovered for Earth-Mars, Earth-Venus, Mars-Earth, Venus-Earth, and even Mars-Venus and Venus-Mars!

Image of Venus taken by NASA’s Pioneer-Venus Orbiter in 1979. (Credit: NASA)

It is a tantalising prospect that instead of mounting a massive rocket based mission to get to Mars or even Venus, that the use of Near Earth Objects (NEO) might provide a natural solution. They would certainly provide a fast transfer between planets but would still require some form of technological solution to radiation protection. The quicker the journey, the lower the risk from radiation so careful selection is an important part of the process. 

The team have produced quite an extensive list of potentials NEO’s for transfers between the inner planets but as new NEO’s are discovered the list will grow. The work provides a snapshot in time of the possible candidates but it requires on going work to keep the list up to date as more asteroids are discovered and orbital elements are refined. NASA’s NEO Surveyor mission has been set the challenge to find more than 90% of all  NEO’s larger than 140 metres in diameter. This will certainly provide a useful resource to the study.

An artist’s conception of an NEO asteroid orbiting the Sun. Credit: NASA/JPL.

Among the asteroids identified, size and proximity to the target planet needs to be considered. Analysis of the overall mission needs to be carefully worked too. If a spacecraft stays in open space for a longer period of time than inside a NEW for example, the effectiveness of the approach must be carefully weighed up. 

It’s an interesting proposition though. With appropriate technological solutions, a carefully selected asteroid can serve not only as a fuel station but also, if shelter is taken beneath the surface for example in caves, could offer radiation protection too. There are significant challenges ahead before this all becomes a reality but with the ever increasing drive to reduce the cost and ecological impact of space flight it is one that most definitely needs further careful analysis. 

Source : The search for NEOs as potential candidates for use in space missions to Venus and Mars

The post Astronauts Could Take an Asteroid Ferry from Earth to Mars appeared first on Universe Today.

Ancient stone goods found across France may have been made by skilled craftspeople in what is now Paris, who traded along vast networks

Meanwhile, in Dobrzyn, Hili notices the changing seasons, but Andrzej is not optimistic:

Hili: We have autumn again. A: This time it’s the autumn of Enlightenment.

Hili: Znowu mamy jesień.
Ja: Tym razem to jest jesień Oświecenia.

 

 

In a post on X/Twitter, antivaxxer turned Trump supporter Robert F. Kennedy, Jr. declared MAHA war on the FDA, should Trump be elected. What would this actually mean in practice?

The post RFK Jr. declares MAHA war against the FDA first appeared on Science-Based Medicine.

Some wires must have gotten crossed, as Matthew hasn’t put up today’s Hili dialogue. But no worries–I called Malgorzata and got it. A day without Hili is like a day without sunshine! So here you go:

Hili: What do you think will happen now? A: Predicting the future is not my business. In Polish: Hili: Jak sądzisz, co teraz będzie.
Ja: Przewidywanie przyszłości to nie mój biznes.

I was up at 5 a.m. as I went to bed early with an incipient cold (or some other virus), and the insomnia is still with me. This morning I leave for Utah, but will put up here two articles I read yesterday as well as a clip from Bill Maher’s “Real Time”. I am still baffled that so many science-oriented skeptics think that one’s biological sex is what one thinks it is, regardless of other traits and despite the truth that what one “thinks” is based on biology (neurons and the like). Onwards and upwards.

Niall Ferguson, who happens to be married to Ayaan Hirsi Ali, and is also seen as a conservative, has what I thought was a good article in The Free Press, which you can access below or find archived here.  It’s about Israel’s continuous refusal to follow America’s marching orders in the Middle East. I’ll give a few quotes (indented):

First, of course, I have to give the usual disclaimer that I’m not a huge fan of Netanyahu, but I do give him credit for prosecuting the war successfully despite repeated American objections. An excerpt (the essay Ferguson refers to is Jake Sullivan’s “7,000-word essay published in Foreign Affairs one year ago”).

Since then, the region has been in a state of upheaval not seen in half a century—since the last surprise attack on Israel almost exactly 50 years previously, on Yom Kippur 1973. And at every single major hinge point of Israel’s war with Iran’s proxies, the U.S. has been as wrong as Sullivan was in that essay.

The White House said don’t go into Gaza. Israel did, and in a sustained campaign killed a high proportion of Hamas fighters. Team Biden-Harris said don’t go into Rafah. Israel ignored those warnings, too, and in February liberated two hostages there. Ten days ago, a routine Israeli patrol in Rafah spotted the mastermind of the massacre, Yahya Sinwar, who was killed soon after. Washington said don’t send troops into Lebanon. Israel sent them anyway and in a matter of weeks has inflicted severe damage on Hezbollah’s positions there.

Biden and Harris said “Ceasefire now!” but Israel had no interest in a ceasefire that gave Hamas breathing space to regroup. Finally, the U.S. warned against Israel directly attacking Iran. An as yet unidentified U.S. government official even appears to have leaked Israel’s plans to Tehran—a scandal that ought to be front-page news. You know what happened next.

The past year has revealed many things—not least the moral confusion of many young Americans—but two major points stand out. First, Israel has pursued a strategy of targeted retaliation of impressive precision and effectiveness. Second, the United States has lost all but a shred of the influence it once had over Israeli policy. Fact: As a share of Israeli national income, U.S. aid peaked at 22 percent in 1979. It’s now down to 0.6 percent.

The political consequences are twofold. First, Prime Minister Benjamin Netanyahu has successfully outmaneuvered his critics at home and abroad, who wrongly assumed that, by relentlessly exaggerating the collateral damage of Israel’s campaign against Hamas, they would prevent Israel from exacting vengeance—and from reestablishing deterrence.

Second, the Biden-Harris administration has been left looking even more hapless in its national security strategy than Jimmy Carter’s did in 1980, when Ronald Reagan swept to victory with a promise to achieve “peace through strength.” The Iranian revolution and the subsequent hostage crisis, combined with the Soviet invasion of Afghanistan, had made 1979 an annus horribilis for Carter.

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Andrew Sullivan despises Trump, and has declared that he’ll vote for Harris, but that doesn’t stop him from calling her out. I’d say that such criticism is fair, since it’s designed not to defeat the Democrats but to correct them. Read by clicking below, or see the piece archived here . “Project Fear” refers to what appears to be Harris’s main campaign strategy: to continuously diss Trump (fair enough, and her criticisms are correct) but not to advance her own policies (not a good tactic). Read the transcript of Harris’s town-hall interview with CNN’s Anderson Cooper, who also dislikes Trump.

An excerpt .from Sullivan:

And so the few undecideds are looking for a positive reason to vote for Harris. And this is the best she could do in her truly pitiable CNN town hall:

I think that the American people deserve to have a president who is grounded in what is common sense, what is practical, and what is in the best interest of the people, not themselves.

Weak. Lame. This is the first presidential candidate who doesn’t seem to want you to know what she’ll actually do, or what she really thinks about anything much, and who responds to every direct question with a meandering digression. Blathering about an “opportunity economy” and a “middle-class background” doesn’t cut it. With Anderson Cooper — who was superb — she memorably crashed and burned.

She had taken a day off to prep and yet still could not tell us what her first Congressional priority would be, what policies of the last four years she would change, how she would prevent illegal immigration, why Biden had not issued this year’s executive orders three years ago, and why she was now in favor of building a wall she once called “stupid, useless, and a medieval vanity project.” When asked to name just one mistake she’s made over the past four years, in life or in office, she said:

I mean I’ve made many mistakes, um, and they range from, you know — if you’ve ever parented a child, you know you make lots of mistakes. Um, in my role as vice president, I mean I’ve probably worked very hard at making sure that, um, I am well versed on issues, and, um, I think that is very important. It’s a mistake not to be well versed on an issue and feel compelled to answer a question.

Calling Michael Scott. Her entire performance was a near parody of why normal people hate the way politicians talk. Every answer seemed to be a form of damage control, not conviction. And her body language … well, a near-literal defensive crouch isn’t confidence-inducing. Nor is it reassuring to think someone who cannot crisply answer a straight question will have to make split-second, life-and-death decisions as president. She seems like a party functionary who has never known real political combat — maybe a decent low-level cabinet member. But president? C’mon. Even the Dem strategists after the town hall were bewildered by her “word salad city” — to quote David Axelrod. Substacker Adam Coleman wrote:

There are moments when she physically squirms as she searches for a canned response to give Anderson Cooper. She’s in a friendly environment on CNN, and Anderson Cooper absolutely hates her opponent, but even his basic questions made her squirm.

No one wants a president who squirms, laughs, and prevaricates on her meandering way to a calculated, canned response. The undecideds don’t. And the base is given nothing really to speak of, apart from abortion and the filibuster. She’s neither persuading the center nor rallying the faithful. Her final trump card is celebrity concerts and endorsements. Have the Dems learned nothing? And no serious presidential candidate should have a closing message like this one:

Let me, if I can, just speak to what people are feeling. We cannot despair, we cannot despair … Let’s not let the overwhelming nature of all this make us feel powerless, because then we have been defeated, and that’s not our character as the American people. We are not ones to be defeated.

Not exactly “Fired up! Ready to go!” is it?

Sullivan speaks the truth here, and I am truly baffled at those who think that Harris is a great candidate and will likely be a good President. Yes, she’s miles better than Trump, but that is still a long distance from “excellent”. I will be glad it she beats Trump, but I will still worry how Harris, who was roundly beaten the last time around, will handle the world’s most important job.  No, I feel no “joy”, just disappointment about how the whole thing was handled, from Biden refusing to bow out early enough to allow a proper selection of a Democratic candidate to Harris pretending that she has “earned” the nomination when in fact she inherited it.

******************

Finally, here’s Bill Maher’s latest news-and-humor clip saying that what Harris needs is a “Sister Souljah moment“. You remember that moment, right? The Wikipedia link just above describes it, as does Maher in the video below. Maher even provides several SS moments that Harris could use.

(I do think that Maher’s comment about Monica Lewinsky was out of line.)

To northern sky watchers, Vega is a familiar sight in the summer sky. It’s one of the brightest stars in the sky and in 2013, astronomers detected a large ring of rocky debris surrounding the planet. The prospect of planets suddenly became a real possibility so astronomers turned the James Webb Space Telescope (JWST) on the star. The hunt achieved 10 times the sensitivity of previous ground based searches but alas no planets were discovered. 

Vega lies in the constellation Lyra and is one of the prominent stars that makes up the Summer Triangle along with Aquila in Altair and Deneb in Cygnus. Vega itself likes 25 light years away from Earth so it is, in astronomical terms, relatively close. It’s a hot blue/white star which has a visible surface temperature of around 9,600 degrees. At this temperature it is hotter than the Sun and in size it is about 2.1 times larger in diameter. 

The track of the ISS near Vega in Lyra. From right to left, the station is passing from sunlight into Earth’s shadow. Its color transitions from white to red. Credit: Bob King

Data captured by JWST has recently been used to study Vega. The space telescope is perhaps the most advanced telescope to be placed into orbit. It was launched in December 2021 as part of a partnership between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA.) It orbits the Sun at the second Lagrange point which is about 1.5 million km away from Earth. As telescopes go it’s not the largest (main mirror is 6.5m across) but by being in space it can out perform many ground-based instruments. 

Among the many instruments on board JWST, NIRCam (Near Infrared Camera) and MIRI (Mid Infrared Camera) have been used to probe the secrets of Vega. Interest was piqued when the Infrared Astronomical Satellite (IRAS) detected an excess of long wavelengths which were attributed to a cold dust ring emitting radiation at 25-100 ?m. Further studies revealed the signal was very similar to the signal from the Kuiper Belt. The discovery led astronomers to the conclusion that it must be the remains of planetary formation. 

MIRI, ( Mid InfraRed Instrument ), flight instrument for the James Webb Space Telescope, JWST, during ambient temperature alignment testing in RAL Space’s clean rooms at STFC’s Rutherford Appleton Laboratory, 8th November 2010.

In a paper written by a team of astronomers led by Charles Beichman from NASA’s Exoplanet Science Institute they describe their attempts to hunt down planets in the ring of debris. They were able to utilise data from NIRCam’s coronographic observations of Vega. Within this data, there were 3 sources identified and analysed using supporting data from MIRI. The sources were assessed to see if astrometric data confirmed an association with Vega. If it were part of the Vega system the data would indicate a mass of these sources between 1 and 3 times mass of Jupiter and a temperature in the region of 250K.

Such an object is likely to have disrupted the smooth disk structure but the MIRI data reveals no such effects. It seems then for now at least, that the debris field around Vega is devoid of evidence of planetary formation. Further studies using the instrumentation on board JWST and other new observatories coming on line may change this view but for now it seems, Vega may just be alone without any planetary system. 

Source : Searching for Planets Orbiting Vega with the James Webb Space Telescope

The post Webb Scans Vega for Planets appeared first on Universe Today.

I’ve been busy at the CSICon conference, which included giving my own 30-minute presentation this morning. I had to modify it to take into account the misguided views of Steve Novella, who gave a talk yesterday about “When Skeptics Disagree.” It turned out to be largely a diatribe about how sex in humans is not binary, and in fact isn’t even to be defined by morphology or physiology. As far as I can see, Novella’s view of sex is that one is born with a “brain module” (which of course is biological) that determines which sex you are. No, not gender, but actual biological sex. You can have a “female” module or a “male module”, and regardless of gametes, hormones, genitalia, and so on, you are whatever sex your module dictates to your self-identification.

That makes no sense, because of course there are plenty of people that have ideas, right or wrong, about what they are, but in the end merely feeling something about your self doesn’t make it objectively true.  Does a full biological man, with the right genitalia, hormones and chromosomes, but who feels that he’s a woman, actually become a woman (or vice versa for women)? Of course not, unless you think that words mean whatever you want them to. This is why I believe that people can claim to be of any gender, but they can’t actually change their biological sex. (Clownfish can, but they are still only male or female.)

And what about those people—yes, they exist—who think they really are in the wrong body, and should be a member of another species, like a horse or a cat? Does that actually make them a cat or horse? Of course not.

One more example. There are people who are nonbinary, but are that way on a temporal basis: they change from feeling male to feeling female on a daily or even hourly basis. (Neil deGrasse Tyson defends this view here.) Does this mean that at one moment they are a male, and at other moments female, or some other unnamed sex in between?  I don’t think so.

Novella, of course, has been banging this drum for a long time (see here and especially the post here). His Science-Based Medicine (SBM) site even removed a favorable review of Abigail Shrier’s book Irreversible Damage because the reviewer, SBM founding editor Harriet Hall, gave it a favorable review (see also here for Novella and Gorski’s pathetic defense of their unethical action). You can read about this fracas on Wikipedia, and find a copy elsewhere of Hall’s “problematic” review.

I was, frankly, appalled at Novella’s position, especially the revision that involved defining one’s sex as the part of the brain that makes you feel what sex you are, irrespective of gonads, gametes, chromosomes, or anything else that people use to define sex. (I use gamete type.). Novella got quite exercised towards the end of his talk, calling those of us who use other traits to define sex as “delusional”, and adding that other definitions of sex ignore or erase transgender folks or those who identify as members of their non-natal sex. This is when I realized that he’s gone full-out progressive woke, to the extent of ignoring scientific fact in favor of a sex definition that comports with his ideology.

Novella instantiated exactly what I was talking about in my own talk two hours ago: the distortion of biological reality in favor of ideology. It’s telling that Novella’s definition of sex was limited exclusively to humans (are foxes or parrots nonbinary?), which tells you immediately that it’s based on ideology. It’s what I call an example of the “reverse naturalistic fallacy”, deciding that what is good for society is what you must see in nature. I can express it more succinctly this way:

OUGHT —> IS 

You see that this is the inverse of the famous naturalistic fallacy, which reverses the position of the two words. But both are fallacies.

It’s sad that first, so many skeptics at the meeting bought into the notion that sex is not just a spectrum, but a spectrum based on brain modules (many people gave Novella a standing ovation). It’s doubly sad that this kind of misguided take on reality comes almost exclusively from the Left. And it’s the reverse naturalistic fallacy that, I think, has helped erode trust in scientists substantially in the last ten years, as well as public confidence in universities. People simply know that sex is not a spectrum, and when a fancy-pants doctor or scientist tells them otherwise, the savvy reaction is to distrust that “authority”

I talked about some of this material, but my one slide critiquing Novella’s views was made hurriedly in my room last night, and I could only put it up for a minute and tell people to take photos of it. But here it is (click to enlarge it):

But enough. Our talks will eventually appear on YouTube when the Center for Inquiry puts them up, and you can judge for yourself.

As for other talks, they’ve been of a high standard; you can see the schedule here.  Last night Neil deGrasse Tyson gave one of his patented science and humor talks based on an upcoming book. It involved things that people argue about at the Thanksgiving dinner table, including vegetarianism, space aliens, Civil War statues, race, and so on. Here’s a photo of the cover of that upcoming book:

And Tyson in mid-lecture.  He is a mesmerizing speaker, though of course I sometimes disagree with him! But I wish I had his eloquence, poise, and humor.

And since today is Caturday, I have one felid-related item. I met a couple, Michelle and Justin, at a cocktail event, and Michelle, who is a professional baker, had made three special cookies just for me. I was really touched, and you can see why:

. . . and a book-related one:

Fancy, no?  They are almost too pretty to eat, but I figure that after I photographed them, I can eat them. But not today, as I’m going to the Bacchanal Buffet at Caesar’s palace for a late lunch, and haven’t eating anything since lunchtime yesterday.

Da Nooz. 

Only one item today as I must rest (I’m coming down with a cold or something grotty):

*Israel, obeying orders of the Biden Administration, struck back at Iran yesterday, scrupulously avoiding Iran’s nukes and oilfields. An excerpt:

The Israeli military said Saturday that it had struck Iran in response to several Iranian attacks on Israel, raising fears that a long-brewing confrontation between two of the most powerful militaries in the Middle East could escalate into an all-out war.

The military said in a statement at 2:30 a.m. that it was “conducting precise strikes on military targets in Iran” in response to more than a year of attacks on Israel by Iran and its allies across the Middle East. Just after 6 a.m., the military said the strikes had concluded.

Iranian officials appeared to downplay the impact. Iran’s national air defense force said that Israel had attacked military bases in three provinces — Tehran and two near the Iraqi border, Ilam and Khuzestan. Iranian air defenses were able limit the damage, the statement said, but it was continuing to assess.

Three news agencies run by different branches of the Iranian authorities said that the city of Tehran itself had not been hit and that civilian airports were operating normally. The blasts were close enough to the Iranian capital for them to be seen and heard by residents, bringing close to home a war that had felt remote for many.

On Saturday, Israeli officials said that more than 100 combat aircraft, including fighter jets and unmanned drones, hit roughly 20 sites in Iran, Syria and Iraq. The officials, who spoke on the condition of anonymity to discuss the military operation, said that Israel targeted air defense systems and long-range missile production sites in Iran.

The Israeli strikes came 25 days after Iran fired waves of ballistic missiles at Israel in response to the assassinations of several officials of Iran and its allies. While Israeli air defenses intercepted many of the Iranian missiles, the attack forced millions of Israelis to take cover in bomb shelters, damaged several homes and air bases and killed a Palestinian in the Israeli-occupied West Bank.

For years, Israel and Iran have fought a clandestine war in which both sides targeted each other’s interests and allies, while rarely taking responsibility for their attacks. That turned into open confrontation, as the war between Israel and Hamas, Iran’s ally in Gaza, pulled the two countries toward a direct clash.

I still would have preferred Israel to go after Iran’s nukes, but of course that could have touched off a big conflagration in the Middle East. Instead, Israel obeyed the marching orders of the Biden Administration, which will, in the end, allow Iran to have nuclear weapons, and after that all hell will break loose.

Stay tuned for more news: tomorrow I head to Utah and the Zion area for a few days with an old friend, and I suspect I’ll have photos.

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All across America, a storm is gathering: from book bans in school libraries to anti-trans laws in state legislatures; fire-bombings of abortion clinics and protests against gay rights. The Christian Right, a cunning political force in America for more than half a century, has never been more powerful than it is right now—it propelled Donald Trump to power, and it won’t stop until it’s refashioned America in its own image.

In Wild Faith, critically acclaimed author Talia Lavin goes deep into what motivates the Christian Right, from its segregationist past to a future riddled with apocalyptic ideology. Using primary sources and firsthand accounts, Lavin introduces you to “deliverance ministers” who carry out exorcisms by the hundreds; modern-day, self-proclaimed prophets and apostles; Christian militias, cults, zealots, and showmen; and the people in power who are aiding them to achieve their goals. Along the way, she explores anti-abortion terrorists, the Christian Patriarchy movement, with its desire to place all women under absolute male control; the twisted theology that leads to rampant child abuse; and the ways conspiracy theorists and extremist Christians influence each other to mutual political benefit.

From school boards to the Supreme Court, Christian theocracy is ascendant in America—and only through exploring its motivations and impacts can we understand the crisis we face. In Wild Faith, Lavin fearlessly confronts whether our democracy can survive an organized, fervent theocratic movement, one that seeks to impose its religious beliefs on American citizens.

Talia Lavin is the author of the critically acclaimed book Culture Warlords. She is a journalist who has had bylines in the New Yorker, the New Republic, the New York Times Review of Books, the Washington Post, and more. She writes a newsletter, The Sword and the Sandwich, which is featured in Best American Food and Travel Writing 2024. She is a graduate of Harvard University with a degree in comparative literature, and was a Fulbright scholar who spent a year in Ukraine. Her first book was Culture Warlords: My Journey Into the Dark Web of White Supremacy. Her new book is Wild Faith: How the Christian Right is Taking Over America.

Shermer and Lavin discuss:

• The Satanic Panic and the McMartin preschool case
• The Recovered Memory Movement
• Multiple Personality Disorder
• Demon possession and exorcisms
• Moral panics
• The Evangelical right is working hard to dominate what it refers to as the Seven Mountains of Societal Influence: Arts and entertainment, business, education, family, government, media, and religion
• How Christian dominance has waxed and waned over the past 50 years
• Opposing abortion by all possible means
• Opposing marriage equality
• Opposing no-fault divorce in favor of hard-to-sever “covenant marriages”
• Opposing out-of-wedlock heterosexual sex
• Christian Zionism: “Christian Zionists have spent more than $65 million in support of ongoing Israeli settlements within the disputed territories of the West Bank,” “Before the Messiah can return, the nation of Israel must be restored; Jerusalem must be a Jewish city; and the Temple, the center of worship and sacrifice in the ancient Jewish world, which was last destroyed by the Romans in 70 AD, must be rebuilt,” writes Lavin. But here’s the rub: For the temple to be rebuilt, the Jewish people have to be “purified with the ashes of a red heifer.” (young, female cow)
• In a poll conducted in 2018 by Christian research organization LifeWay Research, a staggering 80 percent of evangelicals agreed with the statement that the creation of the modern state of Israel was a “fulfillment of Bible prophecy that shows we are getting closer to the return of Jesus Christ.” Some may see this as imminent, others as eventual, though a 2010 Pew poll showed nearly 60 percent of white evangelical Christians in the U.S. expect Jesus Christ to return by 2050.
• Premillenarian dispensationalism, which was developed in the late nineteenth century and holds that the world is divided into eras, or dispensations, which will culminate in Christ’s triumphant return.
• Hal Lindsey’s The Late Great Planet Earth
• Why do Christians want to control female sexuality and reproductive freedom?
• Prostitution and pornography
• Children and families.

If you enjoy the podcast, please show your support by making a $5 or $10 monthly donation.

The TRAPPIST-1 system is a science-fiction writer’s dream. Seven Earth-sized worlds orbit a red dwarf star just 40 light-years away. Three of those worlds are within the habitable zone of the star. The system spans a distance less than 25 times that of the distance from the Earth to the Moon. Oh, what epic tales a TRAPPIST civilization would have! That is, if life in such a system is even possible…

Therein lies the problem. Although the vast majority of potentially habitable worlds orbit red dwarf stars, that doesn’t mean most inhabited worlds have a red dwarf sun. Red dwarfs are known to be violently active in their youth. They emit powerful flares that might strip nearby planets of their atmospheres, and even if a planet can hold on to its sky, it would still be bathed in powerful radiation. Only when a red dwarf matures is it calm and stable. This is very different from larger stars such as our Sun, which are reasonably calm throughout their lives. Since potentially habitable red dwarf planets must orbit very close to their stars, there is a worry that even in the best conditions, life on such a world could never get a foothold. The environment is just too harsh. But a new study gives exobiologists some surprising hope.

The study focuses on red dwarf superflares and the radiation they emit. These flares emit a great amount of x-rays and ultraviolet radiation. For a young red dwarf planet with an atmosphere, most of the x-rays would never reach the surface, but the young world would still be bathed in UV radiation. The team wanted to know how hostile that UV would be to early life, so they bathed microbes in UV.

The study looked at two types of bacteria. Deinococcus radiodurans is a variety known to be UV tolerant, while Escherichia coli is known to be susceptible to radiation. They bathed each variety in ultraviolet radiation levels that would be typical at the distances of the TRAPPIST worlds e, f, and g, which are the most potentially habitable. The results weren’t good for the E. coli variant, as a simulated flare sterilized them below the limit of detection for the innermost world and some survival for the most distant one. But the D. radiodurans did fairly well. Only about 1 in 600 million survived a simulated flare for the closest world, but given the typical time span between flares, the bacteria would maintain a foothold. And, of course, with regular flares, there would be an evolutionary pressure to become more UV resistant.

So it seems that while early life in the TRAPPIST system might have a tough evolutionary road, the superflares wouldn’t sterilize the planets. Life might be common for red dwarf worlds after all.

Reference: Abrevaya, X C, et al. “An experimental study of the biological impact of a superflare on the TRAPPIST-1 planets.” Monthly Notices of the Royal Astronomical Society (2024): stae2433.

The post Could Life at TRAPPIST-1 Survive the Star's Superflares? appeared first on Universe Today.

What's the Word: Annular; News Items: Europa Clipper, Illusion of Information Adequacy, Seeding the Atmosphere, Exomoon, Psychology of Scare; Who's That Noisy; Your Questions and E-mails: Replaceable Batteries; Science or Fiction

Meanwhile, in Dobrzyn, Hili is thinking about religion:

Hili: Lack of God causes complications. A: What kind of complications? Hili: It disperses responsibility.

Hili: Brak Boga powoduje komplikacje.
Ja: Jakiego rodzaju?
Hili: Rozprasza odpowiedzialność.

Exoplanets are a fascinating aspect of the study of the Universe. TRAPPIST-1 is perhaps one of the most intriguing exoplanet systems discovered to date with no less than 7 Earth-sized worlds. They orbit a red dwarf star which can unfortunately be a little feisty, hurling catastrophic flares out into space. These flares could easily strip atmospheres away from the alien worlds rendering them uninhabitable. A new piece of research suggests this may not be true and that the rocky planets may be able to maintain a stable atmosphere after all. 

Exoplanets are alien worlds outside of our solar system orbiting other stars. Their discovery in the 1990’s was just the beginning and to date over 5,000 have been identified. They vary massively in composition from small, rocky Earth-sized planets to gas giants like Jupiter. A few of them orbit in the host star’s habitable zone raising the tantalising possibility that life may exist out there in the universe. 

All manner of techniques and telescopes have been used to hunt for exoplanets and to explore their nature. More recently the James Webb Space Telescope (JWST) which was launched in late 2021 has been engaged to that end. The design of the JWST is such that it is capable of observing nearby exoplanets in greater detail than before. 

Artist impression of the James Webb Space Telescope

TRAPPIST-1 is 40 light years away in the constellation Aquarius. It is one of the most fascinating exoplanetary systems discovered to date with 7 Earth-sized planets in orbit around a cool dwarf star. Like all stars, TRAPPIST-1 has a habitable zone, a region around the star within which, the conditions are likely to be conducive to life for any planet that happens to be orbiting at that distance. TRAPPIST-1 has 3 of the 7 planets orbiting in this zone offering a tantalising possibility of extra-terrestrial life. 

The planets of TRAPPIST-1 are classic rocky objects in orbit around an M-dwarf star. These stars are the most common in the universe but previous studies suggest the intense UV radiation from TRAPPIST-1 would fry any atmosphere or surface water. It has been thought that the hydrogen molecules would escape, leaving behind significant quantities of reactive oxygen which would likely inhibit the development of organic chemistry. 

Illustration of the tidally locked world TRAPPIST-1f. Credit: NASA/JPL-Caltech

A recent study led by the University of Washington has been published in the journal Nature Communications which suggests an alternative theory. The team led by Joshua Krissansen-Totton suggest that instead, a stable atmosphere can be created and sustained following an alternative sequence of events. 

During the evolution of the planet, and following its molten state, millions of years of cooling lead to the solid rocky planets we see today. They report that their data shows hydrogen and other light gasses escaped out into space for planets near to the star. For those that are further away where things are a little cooler, the hydrogen reacted with oxygen and iron deep inside the planet producing water and other heavier gasses. These processes may have created a stable atmosphere after all. 

Observations from the JWST can detect higher levels of thermal infrared energy from the inner planets and they reveal the absence of a thick atmosphere. The team suggest more distant planets may have a more stable environment that might even produce a habitable environment. JWST has to date, been unable to detect atmospheres but with new ground based telescopes coming online and with new imaging techniques, the TRAPPIST-1  planets in the habitable zone may soon reveal their mysteries. 

Source : Rocky planets orbiting small stars could have stable atmospheres needed to support life

The post Red Dwarf Stars Might Be Able to Hold Onto Their Atmospheres After All appeared first on Universe Today.

Researchers have created a graphene-enhanced, 3D-printable concrete that improves strength and reduces carbon emissions by 31%, advancing sustainable construction.

A new technique for growing quantum dots has not only found a new, more efficient way to build a useful type of quantum dot, but also opened up a whole group of novel chemical materials for future researchers' exploration. Replacing organic solvents with molten salt lets researchers grow 'previously unimaginable nanocrystals.'

Infrared astronomy has revealed so much about the Universe, ranging from protoplanetary disks and nebulae to brown dwarfs, aurorae, and volcanoes on together celestial bodies. Looking to the future, astronomers hope to conduct infrared studies of supernova remnants (SNRs), which will provide vital information about the physics of these explosions. While studies in the near-to-mid infrared (NIR-MIR) spectrum are expected to provide data on the atomic makeup of SNRs, mid-to-far IR (MIR-FIR) studies should provide a detailed look at heated dust grains they eject into the interstellar medium (ISM).

Unfortunately, these studies have been largely restricted to the Milky Way and the Magellanic Clouds due to the limits of previous IR observatories. However, these observational regimes are now accessible thanks to next-generation instruments like the James Webb Space Telescope (JWST). In a recent study, a team led by researchers from Ohio State University presented the first spatially resolved infrared images of supernova remnants (SNRs) in the Triangulum Galaxy (a.k.a. Messier 33). Their observations allowed them to acquire images of 43 SNRs, thanks to the unprecedented sensitivity and resolution of Webb’s IR instruments.

The team was led by Dr. Sumit K. Sarbadhicary, a former Postdoctoral Fellow with OSU’s Center for Cosmology & Astro-Particle Physics (CCAP) and current Assistant Research Scientist at Johns Hopkins University (JHU). He was joined by multiple astronomers and physicists from OSU, the Harvard & Smithsonian Center for Astrophysics, the Flatiron Institute’s Center for Computational Astrophysics, the University of Heidelberg’s Institute for Theoretical Astrophysics, the National Radio Astronomy Observatory (NRAO), and the Space Telescope Science Institute (STScI). The paper that describes their findings is being reviewed for publication in The Astrophysical Journal.

The Crab Nebula, a supernova remnant, observed by the JWST. Credit: NASA/ESA/JWST

As they explain in their study, SNRs in the Milky Way and Magellanic clouds are the best studied in the Universe because they are the closest. This has allowed astronomers to conduct detailed studies that revealed their structures at most wavelengths, including infrared. As Dr. Sarbadhicary told Universe Today via email, studies of these SNRs have taught astronomers a great deal. This includes dust production, the composition of supernova explosions, and the physics of astrophysical shock waves – particularly those that travel through dense gas clouds where new stars could be forming. 

However, as Sarbadhicary explained, these studies have still been confined to our galaxy and its satellites, which has limited what astronomers can learn about these major astronomical events:

“[The] only thing is, we haven’t quite been able to step outside the Magellanic Clouds and explore SNRs in more distant galaxies in the infrared. We know that other Local Group galaxies such as Andromeda (M31), and Triangulum (M33) have several hundreds of SNRs, so there is a tremendous potential for building statistics. Additionally, infrared-emitting SNRs are a somewhat rare breed, found mostly in explosions that happened close to dense molecular gas that is either part of the interstellar medium, or material lost by the progenitor star before explosion. So having more objects would be really helpful.”

The first generation of SNR studies at infrared wavelengths were conducted with NASA’s Infrared Astronomical Satellite (IRAS) and the ESA’s Infrared Space Observatory (ISO). Despite their limited spatial resolution and the confusion of peering through the Galactic plane, these observatories managed to identify about 30% of SNRs in the Milky Way between 10 and 100 micrometers (?m), which corresponds to parts of the Medium and Far-Infrared (MIR, NIR) spectrum.

Artist’s impression of the Herschel Space Telescope. Credit: ESA/AOES Medialab/NASA/ESA/STScI

In recent decades, IR astronomy has benefitted immensely from missions like NASA’s Spitzer Space Telescope and the ESA’s Herschel Space Observatory. These observatories boast higher angular resolutions and can conduct surveys in broader parts of the IR spectrum – 3 to 160 ?m for Spitzer and 70 to 500 ?m for Herschel. Their observations led to wide-field Galactic surveys – the Galactic Legacy Infrared Midplane Survey Extraordinaire (GLIMPSE), the MIPS Galactic Plane Survey (MIPSGAL), and the Herschel infrared Galactic Plane Survey (Hi-GAL) – and the first high-quality extragalactic IR surveys of SNRs.

“Unfortunately, the angular resolution of the Spitzer telescope (JWST’s predecessor) was just not good enough to recover the same spatial detail in more distant galaxies,” added Sarbadhicary. “While you might see a faint blip with Spitzer, it would be hard to tell (at these distances) if it’s from the SNR or some blend of stars and diffuse emission.” Fortunately, the situation has improved even more with the deployment of the James Webb Space Telescope (JWST). According to Sarbadhicary, Webb’s increased resolution and advanced IR instruments are providing deeper and sharper views of SNRs in the near- and mid-infrared wavelengths:

“We had already seen JWST’s potential for revolutionizing studies of SNRs from crisp new images of known SNRs such as Cassiopeia A in our Galaxy and 1987A in the Large Magellanic Cloud, published in recent papers. The images revealed an unprecedented amount of detail about the explosion debris, material lost by the star prior to the explosion, and much more.

“This superior combination of sensitivity and angular resolution also now enables JWST to recover images of SNRs in galaxies nearly 20 times farther than the Magellanic Clouds (e.g., M33 in our paper), with the same level of detail found by Spitzer in SNRs in the Magellanic Clouds. What is particularly helpful because of JWST’s high angular resolution is that we are less likely to confuse SNRs with overlapping structures such as HII regions (gas photoionized by massive stars).” 

JWST’s near-infrared view of the star-forming region NGC 604 in the Triangulum galaxy. Credit: NASA, ESA, CSA, STScI

For their study, Sarbadhicary and his team leveraged archival JWST observations of the Trangulum Galaxy (M33) in four JWST fields. Two of these covered central and southern regions of M33 with separate observations using Webb’s Near-Infrared Camera (NIRCam) and its Mid-Infrared Imager (MIRI). The third involved MIRI observations of a long radial strip measuring about 5 kiloparsecs (~16,300 light-years), one covering the giant emission nebula in M33 (NGC 604) with multiple NIRCam and MIRI observations. They then overlapped these observations with previously identified SNRs from multi-wavelength surveys.

They also considered the volumes of multi-wavelength data previous missions have obtained of this galaxy. This includes images of stars acquired by the venerable Hubble and cold neutral gas observations conducted by the Atacama Large Millimeter-submillimeter Array (ALMA) and the Very Large Array (VLA). As Sarbadhicary indicated, the results revealed some very interesting things about SNRs in the Triangulum Galaxy. However, since their survey covered only 20% of the SNRs in M33, he also noted that these results are just the tip of the iceberg:

“The most surprising finding was the presence of molecular hydrogen emission in two out of the three SNRs where we had F470N observations (a narrowband filter centered on the 4.7-micron rotational line of the hydrogen molecule). Molecular hydrogen is by far the most abundant molecule in interstellar gas, but because of the symmetry of the molecule, it cannot produce visible radiation at the typical cold temperatures of interstellar gas. Only when heated by shocks or ultraviolet emission does H2 emit radiation (such as at 4.7 microns), so it is a very useful tracer of shocks hitting dense molecular gas, where star formation occurs.”

While astronomers have seen this emission in several SNRs within the Milky Way, this was the first time such observations have been made of an extragalactic source. “The JWST data also revealed that between 14-43% of the SNRs show visible infrared emission,” added Sarbadhicary. “The brightest infrared SNRs in our sample are also some of the smallest in M33 and the brightest at other wavelengths, especially X-ray, radio, and optical. This means that the shocks in these SNRs are still traveling relatively fast and hitting high-density material in the environment, leading to a substantial amount of the shock energy being radiated into infrared lines and dust that are illuminating the emission seen in our broadband images.”

JWST observations of 80 objects (circled in green) that changed in brightness over time, most of which are supernovae. Credit: NASA/ESA/CSA/STScI/JADES Collaboration

The results show how Webb’s high angular resolution will allow astronomers to conduct highly accurate infrared observations of large populations of SNRs in galaxies beyond the Magellanic Clouds. This includes M33, the Andromeda Galaxy (M31), and neighboring Local Group galaxies like the Southern Pinwheel Galaxy (M83), the Fireworks Galaxy (NGC 6946), the Whirlpool Galaxy (M51), multiple dwarf galaxies in the Local Group, and many more! Said Sarbadhicary:

“Personally, I am quite excited about being able to study the population of SNRs impacting dense gas with JWST since the physics of how shocks impact dense gas and regulate star formation in galaxies is a major topic in astronomy. The infrared wavelengths have a treasure trove of ionic and molecular lines (like H2 we found) that are excited in warm, high-density gas clouds by shocks, so these observations can be really useful.

“There are also some rare Cassiopeia A-like SNRs in these galaxies that are very young and rich in ejecta material from the explosion, and JWST can provide a lot of new information from emission lines in the infrared. Another big area of study is dust and how they are produced and destroyed in shocks.”

Further Reading: arXiv

The post Webb Finds Dozens of Supernovae Remnants in the Triangulum Galaxy appeared first on Universe Today.

Moons are the norm in our Solar System. The International Astronomical Union recognizes 288 planetary moons, and more keep being discovered. Saturn has a whopping 146 moons. Every planet except Mercury and Venus has moons, and their lack of moons is attributed to their small size and proximity to the Sun.

It seems reasonable that there are moons around exoplanets in other Solar Systems, and now we’re going to start looking for them with the James Webb Space Telescope.

The Cool Worlds Lab is part of the Columbia University Astronomy Department and is led by assistant professor David Kipping, a well-known British/American astronomer. The Lab focuses on cool exoplanets with wide orbits around stars. “In this regime, orbital dynamics and atmospheric chemistry diverge from their hot counterparts, and the potential for satellites, rings, and habitability become enhanced,” the Lab’s website says. Exomoons around these planets are part of the Lab’s focus, and Kipping is an author and co-author of several papers about exomoons.

There’s a lot of active discussion in the astronomy world about exomoons, how to find them, and how to confirm them. Currently, there are no confirmed exomoons, only a list of candidates, some of which should be in habitable zones if they’re real.

Kipping and his team have succeeded in getting some JWST observation time to look for an exomoon. Back in February, his proposal was selected. “We have been hoping to find exomoons for a very long time,” Kipping says in a YouTube video announcing the beginning of their JWST observations, adding that exomoons have been “a continuous thread in my career.”

Now, Kipping and the Cool Worlds Lab is being given a chance to use the world’s most powerful space telescope to observe an exoplanet named Kepler-167e. Kipping himself found this planet about 10 years ago, and there’s something special about it. It’s a Jupiter analogue and a very rare example of a long-period transiting gas giant. Because Jupiter has so many moons, Kipping and others argue that Kepler-167e is a strong candidate to also have moons.

An artist’s illustration of Kepler-167e, a Jupiter analogue in a distant solar system. At the time of writing, the JWST is observing this planet and looking for signs of an exomoon. Image Credit: NASA Eyes On Planets

The planet only transits its star once every three years, and the next transit is happening right now. In fact, it started yesterday morning, and the JWST was watching on behalf of the Cool Worlds Lab. The JWST has given the Lab 60 hours—2 and a half days— of observing time. Those observations are happening right now, and if all goes well, we may have our first strong detection of an exomoon.

The data from these observations is exclusive to the Cool Worlds Lab for one year. “We have a year before the data goes public, and that’s fairly normal with JWST data,” Kipping said.

Kipping says they have to be cautious when they get their initial results. “I’ve been in this situation many times. You get the data on the first day. You see a dip and you’re like ‘That’s it. We’re there. We’ve got a moon.’ ” But a few weeks or months later, it could turn out to not be real. “So we don’t want to get people’s excitement up prematurely,” he said.

Looking for exomoons is extremely challenging and Kipping led an effort to find some in Kepler’s data. “We surveyed probably on the order of 300 or 350 exoplanets during our time, and only two real candidates popped up over this entire analysis,” Kipping said in an interview with Fraser Cain earlier this year. One of the candidates was Kepler-1625 b, and even then, they only had the “smallest of hints from the Kepler data that there was something there,” he said.

In 2018, researchers presented evidence in support of an exomoon orbiting Kepler-1625b, a super Jupiter 8,200 light-years away. Subsequent research poured cold water on the moon’s existence. Image Credit: By ESA/Hubble, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=73369715

Kipping told Universe Today that “we’re really pushing these data sets to their limits to even get these signals.”

But the JWST’s data should be more robust than Kepler’s. Kepler was an automated survey, while the JWST is a different beast. Kepler had a fixed field of view and a primary mirror only 0.95 meters in diameter. Its sole job was to detect exoplanets that transited in front of their stars. The JWST has a 6.5-meter mirror, multiple instruments, including cameras and spectrographs, and a system of filters. It’s far more capable than Kepler, as almost everyone knows.

Kipping is hopeful that the JWST will be able to detect moons as small as Ganymede and Callisto. There’s a chance that the JWST will detect a slam-dunk exomoon and that it’ll be clear to everyone. “That’s the dream scenario,” Kipping says. However, this set of observations will be scientifically rich whether they detect an exomoon or not because the JWST will be able to measure other things about the planet.

“But there’s also a scenario where we don’t see anything,” Kipping said. If that happens, it would also be a significant finding. “We would essentially have to rip up the textbook,” Kipping said. “If we don’t see a Titan, if we don’t see a Ganymede, we don’t see a Callisto, that is telling us something quite profound about Moon formation, maybe that our Solar System’s kind of special.”

Enhanced image of Ganymede taken by the JunoCam during the mission’s flyby on June 7th, 2021. Ganymede is our Solar System’s largest moon and potentially holds a subsurface ocean. Ganymede and other moons in our Solar System are suspected of having warm, potentially life-supporting oceans under layers of ice. It seems highly likely that some exomoons will also have oceans and be potentially habitable. Image Credit: NASA/JPL-Caltech/SwRI/MSSS/Kalleheikki Kannisto

This mirrors what we used to say about exoplanets. Prior to the Kepler mission, which found over 2,500 exoplanets, we weren’t certain if our Solar System’s planet population was normal or extraordinary. Now we know that exoplanets are likely orbiting every star. (Though our Solar System is still special.)

We may be on the verge of an age of exomoon discovery, just as we were prior to Kepler’s launch. The Cool Worlds Lab exomoon observations are just one of five exomoon observing efforts the JWST has approved, and the JWST isn’t the only telescope that will be searching for them. The ESA’s upcoming PLATO (PLAnetary Transits and Oscillations of stars) mission will study exoplanets in habitable zones around Sun-like stars, and it will also discover exomoons.

Kipping is boiling over with enthusiasm about the JWST’s observations of Kepler-167e. He discovered the planet, and if he and his team were able to find the first confirmed exomoon around it, it would be quite an achievement.

“It’s an amazing opportunity that we have to potentially test some long-standing theories,” Kipping said, adding that it’s also a “dream I’ve had for my entire career.”

For updates on the observations, follow Cool Worlds on YouTube.

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