MSL Curiosity is primarily a rockhound. It’s at Gale Crater, examining the rocks there and on Mt. Sharp, which sits in the middle of the crater and rises 5.5 km above the crater floor. But Curiosity is also a skywatcher, and its primary camera, Mastcam, was built with Martian clouds in mind.
When the sun set on Mars’ Gale Crater on January 17th, MSL Curiosity spent 16 minutes capturing images of the sky with Mastcam, the rover’s primary camera system. The images are part of an effort to understand noctilucent clouds, which are made of CO2 ice and only form over certain regions.
In the animation below, the 16 minutes of images have been sped up by about 480 times. “The white plumes falling out of the clouds are carbon dioxide ice that would evaporate closer to the Martian surface,” NASA says in a press release. “Appearing briefly at the bottom of the images are water-ice clouds travelling in the opposite direction roughly 31 miles (50 kilometres) above the rover.”
Earth has noctilucent clouds, too. They form in the upper atmosphere and are only visible during twilight when the atmosphere’s lower layers are in the shade and the upper atmosphere is sunlit. They form from water ice crystals between 76 to 85 km altitude and are the highest clouds in the atmosphere.
Mars’ noctilucent clouds are similar, but the main difference is that they contain carbon dioxide ice. They form at an altitude of around 60 to 80 km and are also classified as mesospheric clouds. On Mars, they occur in the Fall over the southern hemisphere. Only Mars’ high-altitude clouds containing carbon dioxide ice display iridescent colours.
This is the fourth year in succession that Curiosity has seen these noctilucent clouds. Its Mastcam instrument has different filters that let it see different wavelengths of light, and some of those filters are used to study the composition and particle size in clouds. It also has stereo vision, which helps scientists determine cloud height, shape, and the speed at which they’re moving. It can also observe the Sun through filters and determine how much sunlight the atmosphere is blocking. That tells scientists how much dust and ice is in the atmosphere and how it changes over time.
A November 2024 paper titled “Iridescence Reveals the Formation and Growth of Ice Aerosols in Martian Noctilucent Clouds” summarized Curiosity’s images and findings. The lead author is Mark Lemmon, an atmospheric scientist with the Space Science Institute in Boulder, Colorado.
“I’ll always remember the first time I saw those iridescent clouds and was sure at first it was some color artifact,” he said in a press release. “Now it’s become so predictable that we can plan our shots in advance; the clouds show up at exactly the same time of year.”
These clouds form only in early Martian fall and only in the southern hemisphere. Their iridescence is from uniform particle size, which indicates that the clouds had a brief evolution in a uniform environment. When clouds are both noctilucent and iridescent, they’re called nacreous clouds. It’s interesting to note that these colours would be easily seen by an astronaut on the Martian surface.
This figure from the paper shows iridescent clouds in cylindrical projections. Each image was taken on a separate day. (d) is twice the resolution of the others. (e) shows a corona in the clouds caused by low variance in CO2 ice particle size. Image Credit: Lemmon et al. 2024.One of the mysteries behind these clouds concerns their location. They’re only seen in Mars’ southern hemisphere, and the Perseverance rover, which is in the Jezero Crater in the northern hemisphere, has never seen them. It seems pretty clear that they only form in certain locations, but the reasons why are unknown.
Lemmon says that gravity waves, which are atmospheric phenomena separate from astrophysical gravitational waves, could be responsible. They cool the atmosphere and could give rise to clouds of frozen CO2. “Carbon dioxide was not expected to be condensing into ice here, so something is cooling it to the point that it could happen. But Martian gravity waves are not fully understood, and we’re not entirely sure what is causing twilight clouds to form in one place but not another,” Lemmon said.
Scientists need more data to better understand these clouds. Curiosity wasn’t the only one to see them; the InSight lander did, too. But they could only see for a few hundred kilometres around their landing sites and their data is incomplete. “Orbiters capable of sunset and twilight times could constrain the cloud altitude,” Lemmon and his co-authors write in their paper.
There are unanswered questions about these clouds. Scientists would like to understand how quickly particles in these clouds evolve. They’d also like to know what the nature of the corona-forming layer is. A larger data sample could help answer these questions, as could more time-lapse imagery.
The post Curiosity’s Other Important Job: Studying Martian Clouds appeared first on Universe Today.
Perhaps I’m into sappy music today, but let’s end the day, as we started it, with romantic music, and one of my favorite pop songs. This one is “I’ll never love this way again,“, and no, even though it’s sung by Dionne Warwick, it wasn’t written by Burt Bachrach but by Richard Kerr and Will Jennings. And it was produced by Barry Manilow, whom you can see below.
This live version below has both Warwick on vocals and Manilow on the keyboard (and some vocal harmony). It counts as one of my “lost love” songs (I have a list) because she realizes that her great romance is doomed to disappear (“before the good is gone”, “I won’t turn my head in sorrow if you should go away”).
Warwick was a great vocalist, and had a lot of good songs, but now she’s forgotten. Would anybody now in college have even heard her name?
Here’s what the Guardian considers her best song, though I don’t agree, though it’s very good. It was written by Burt Bachrach and Hal David, and performed here by Warwick the year after it was written (1964, when Warwick was 24).
I have a friend with Alzheimer’s so I was especially depressed to read Jesse Singal’s discussion of a new book, Doctored, claiming that research on both Alzheimer’s disease and drugs that purport to ameliorate is all badly flawed, even fraudulent. You can read Singal’s discussion below (free access by clicking on the headline), and access the book on Amazon by clicking on the cover below.
An excerpt from Singal:
In his book, Piller, an investigative reporter at Science magazine, presents copious evidence of severe fraud, negligence, and buck-passing in Alzheimer’s research. From fabricated images published in major research journals (many of them still unretracted) to data manipulation conducted by pharmaceutical companies to the complete negligence of federal watchdogs, Piller’s reporting demonstrates indisputably that the field of Alzheimer’s research is in sorry shape.
Things are so bad, in fact, that the dominant theory that has guided researchers’ efforts this century — that Alzheimer’s symptoms are caused by the buildup of proteins called “amyloid plaques” in the brain — is now in serious question. That might explain why, as Piller notes, a recent meta-analysis of the available research found no evidence that any of the available Alzheimer’s drugs cause noticeable improvements in the cognition or daily functioning of patients. We’re two decades and many billions of dollars into the modern era of Alzheimer’s research, and we have precious little to show for it — a particularly dire state of affairs given that this dread condition is only going to hit us harder as America’s population continues to age. Piller’s book, which was released February 4, tells the story of a wild and heartbreaking goose-chase.
While Doctored is gripping in its own right, it also serves as a warning about the collapse of trust in expert authority. Thanks to the capacious new markets for crankery carved out by social and “alternative” media — not to mention a worldwide populist revolt against “the establishment” in general — there’s more grifting and science-denial than ever before, and the worst purveyors of pseudoscientific sludge rake in millions precisely by positioning themselves in opposition to mainstream science.
The lesson for scientists is to clean up their act and to stop misleading people about their work. I mean, I never had any doubt whatever that Alzheimer’s was caused by plaques in the brain. Now that is not at all certain; the plaques could be a byproduct or a correlate and not a cause. If there’s that much uncertainty about it, why haven’t I heard about it. Of course, journalists are responsible for this, too, but good scientific journalism is a species going extinct.
I believe that Singal has already been demonized on BlueHairSky, though he hasn’t been banned. The reason: the place is full of immigrants from Twitter who are “progressive” liberals and couldn’t stand the free speech on X. Singal described his apostasy:
The background here is that a subset of users on Bluesky disagree with my reporting on youth gender medicine—a subject I’ve been investigating for almost a decade, and have written about frequently, including in The Atlantic and TheEconomist. (I’m currently working on a book about it, commissioned by an imprint of Penguin Random House.) I’m not going to go deep here, but I’d argue that my reporting is in line with what is now the mainstream liberal position: See this Washington Post editorial highlighting “scientists’ failure to study these treatments slowly and systematically as they developed them.”
But perhaps because I wrote about this controversy earlier than most journalists, and have done so in major outlets, I’ve become a symbol of bigotry and hatred to a group of activists and online trolls as well as advocacy orgs like GLAAD that push misinformation about the purported safety and efficacy of these treatments, and attempt to punish journalists like Abigail Shrier for covering the controversy at all.
Bluesky appears to have attracted a particularly high number of these trolls, and even before I arrived on the platform, some of them were making sure I wouldn’t feel welcome there. Nora Reed, an online influencer and cultural critic, wrote in November that “I think we need a plan for if Jesse Singal shows up here in advance.”
Back to his own Substack, though; Singal won’t win many friends by arguing that both scientists and liberals have exacerbated the problem, the former by acting precipitously or even duplicitously (the attempt to dismiss a lab-leak theory for the covid virus by scientific officials in the Biden ambit is a good example), while the left-wing public by always saying “trust the science” without realizing that a. scientists are human, with all the good and bad behavior that implies and b. science like investigating covid moves quickly, and what is true today could be false tomorrow.
But I shouldn’t exculpate the Right as well. After all, that’s the side of the political spectrum that still pushes creationism as well as quacks like RFK Jr. And Trump and his cronies are busy slashing scientific research almost willy-nilly. Singal, though, concentrates on the Left, perhaps because that’s where he resides:
At a time of such uncertainty and such dangerous overcorrection, it can feel awkward or difficult to point out, as Piller does in Doctored, just how broken some of our cherished mainstream scientific institutions are. Isn’t that playing right into Trump’s hands?
I don’t think so. The strategy adopted by many mainstream liberals in response to the populist surge — effectively, plugging our ears and chanting “trust the science” over and over — might be comforting, in that it offers a Manichaean worldview in which improving the world is a relatively straightforward matter of convincing people of their own ignorance so that they will board the science train with the rest of us.
But this effort has clearly failed. Some populist distrust of mainstream science is unwarranted and harmful, such as most strains of vaccine skepticism, but in plenty of instances, they are more or less correct not to automatically trust mainstream scientists, even if they arrive at that conclusion for reasons some of us might find uncouth. (Update: I added ‘automatically’ post-publication because I think it’s an important modifier here.)
In other words, while it’s easy to accuse those red-staters out there of exhibiting an alarming lack of faith in science, especially now that their wrecking-ball avatar is in power, it’s harder — and arguably just as important — to ask whether perhaps we have too much faith in it. The scientific establishment hasn’t exactly covered itself in glory in recent decades, given the replication crises that have roiled multiple fields, the data-fraud scandals popping up everywhere from cancer research to business-school psychology, and the frequently overconfident proclamations experts made about thorny Covid-era issues like mask mandates and school closures. And yet liberals tend to continue to reflexively trust many institutions that haven’t earned it, to the point where some of us have turned this sentiment into a mantra: “Science is real,” you will see on signs planted in front of many liberal homes.
I will read this book, as I’m particularly interested in how “fraud” was involved in Alzheimer’s research. Here’s one bit from Singal:
Piller’s book provides numerous damning examples of the difference between science as we idealize it and science as it is practiced by real-life human beings. For example, much of the data fraud in Alzheimer’s research, alleged and proven, involves doctored images. This fraud was uncovered not by journal editors or peer-reviewers — the individuals supposedly responsible for such quality-control — but by unpaid sleuths “who use pseudonyms to post comments” online, as he writes, in the hopes of someone who matters noticing and acting. (One notable exception is Elizabeth Bik, a Dutch microbiologist and legendary image sleuth who has taken on Alzheimer’s fraud.)
Who would have thought that we’d be catching so much fraudulent work by analysis of published images. One might conclude that reviewers of manuscripts aren’t doing their work, but I suspect that a lot of the fraud involves the same images repeated in different papers, and no reviewer has time to compare images in a submitted manuscript to other images by the same authors, but in different journals.
Doctored was released February 4 of this year.
To avoid making this post too long, I’ve put the book-publisher’s (Simon and Schuster’s) description below the fold. Click “read more” to see it:
Simon and Schuster description here
Nearly seven million Americans live with Alzheimer’s disease, a tragedy that is already projected to grow into a $1 trillion crisis by 2050. While families suffer and promises of pharmaceutical breakthroughs keep coming up short, investigative journalist Charles Piller’s Doctored shows that we’ve quite likely been walking the wrong path to finding a cure all along—led astray by a cabal of self-interested researchers, government accomplices, and corporate greed.
Piller begins with a whistleblower—Vanderbilt professor Matthew Schrag—whose work exposed a massive scandal. Schrag found that a University of Minnesota lab led by a precocious young scientist and a Nobel Prize–rumored director delivered apparently falsified data at the heart of the leading hypothesis about the disease. Piller’s revelations of Schrag’s findings stunned the field and the public.
From there, based on years of investigative reporting, this “seminal account of deceit that will long be remembered” (Katherine Eban, author of Bottle of Lies and Vanity Fair special correspondent) exposes a vast network of deceit and its players, all the way up to the FDA. Piller uncovers evidence that hundreds of important Alzheimer’s research papers are based on false data. In the process, he reveals how even against a flood of money and influence, a determined cadre of scientific renegades have fought back to challenge the field’s institutional powers in service to science and the tens of thousands of patients who have been drawn into trials to test dubious drugs. It is a shocking tale with huge ramifications not only for Alzheimer’s disease, but for scientific research, funding, and oversight at large.
Venus is very variable. Its surface constantly changes from volcanic activity, and the difference between its lower and upper atmosphere is night and day, with a dramatic change in sulfuric acid concentration. So, designing a system that works for all parts of Venus is particularly challenging. NASA thinks they might be on to a new idea of how to do so and has funded Ben Hockman, a roboticist at the Jet Propulsion Laboratory, to work on a tethered atmospheric sensor attached to a balloon as part of the NASA Institute of Advanced Concepts Phase I program.
The project, known as the Tethered Observatory for Balloon-based Imaging and Atmospheric Sampling (TOBIAS—assumedly not after the Arrested Development character), is based on a simple principle. On Venus, a very distinct cloud layer, between 47 and 52 km in altitude, separates the relatively stable upper atmosphere similar to Earth’s, with a hellish surface that no probes have yet lasted longer than a few minutes on.
TOBIAS would float a helium-filled balloon in the upper atmosphere, where conditions are Earth-like. Then it would release a “towbody” – a stand-alone sensing platform connected to the balloon by a tether. That tether is intended to be several kilometers long, allowing the towbody to pass through the hazardous cloud layer and, hopefully, take accurate, high-resolution images of Venus’ surface.
Fraser interviews Ben Hockman, the PI for the TOBIAS project.Several design decisions will be the focus of the Phase I NIAC grant. According to Dr. Hockman’s interview with Fraser, one of the most important aspects will be the tether design. The most significant force on the tether wouldn’t be from the towbody itself but from the wind shear. The wind conditions are different enough from where the balloon is located (50-60km altitude) to where the towbody is intended to reside (45km altitude) that the forces on the tether would be strong enough to rip it apart if it’s not designed correctly.
Also, the tether’s material is essential. Standard copper wire could potentially power the towbody, but it would be too heavy to survive the mission’s expected wind shear conditions. Optical fiber could prove a viable alternative, but there are some concerns about the amount of power that could be transmitted that way. According to Dr. Hockman, “People have put power over fiber before.”
Much of that power would go to a cooling system that would make the temperature in that part of the Venusian atmosphere manageable. Dr. Hockman suggests alternative power sources, like solar panels (which would be affected by the same cloud layer that obscures the surface) to wind turbines, which would do well because of the high energy available from the wind but might lead to stability issues with the towbody.
Fraser explains why Venus is a critical step in our space exploration program.Ultimately, if they can get the cable, power, and communication systems on the towbody to work, it could provide atmospheric sensing, and more importantly, direct imaging of the surface of Venus, in a variety of wavelengths. Near-infrared images, which TOBIAS could supply, could help answer outstanding questions about the history of Venusian volcanism.
Dr. Hockman even speculates about the potential for a tethered impactor to land on the surface, grab a sample, and reel itself back up to the balloon. That concept was the subject of a previous year’s NIAC grant, though it’s unclear whether further progress has been made.
TOBIAS would benefit from additional information about the Venusian atmosphere from DaVinci and Veritas, which will also contain instruments to peer through to the surface, just not in the wavelengths that the towbody would enable. Data from those missions could inform the design of TOBIAS’s balloon and tether system, hopefully making it more likely to survive Venus’ extreme conditions.
Venus presents a ton of engineering challenges, as Fraser discusses here.The project still has a long way to go before it has to survive anything, though. NIAC grants, especially Phase I, are meant to encourage very early design studies, many of which are unlikely to receive further funding. But, if Dr. Hockman proves the idea more and receives a Phase II grant sometime in the next few years, a balloon tugging along some sensors might one day reach Venusian skies.
Learn More:
NASA / Ben Hockman – TOBIAS: Tethered Observatory for Balloon-based Imaging and Atmospheric Sampling
UT – A Balloon Mission That Could Explore Venus Indefinitely
UT – The Best Way to Learn About Venus Could Be With a Fleet of Balloons
UT – Is There Seismic Activity on Venus? Here’s How We Could Find Out
Lead Image:
Artist’s concept of TOBIAS
Credit – Ben Hockman / NASA
The post A Balloon With a Tether Could Explore Venus’ Surface appeared first on Universe Today.
As I reported recently, the Presidents of three organismal-biology societies, the Society for the Study of Evolution (SSE), the American Society of Naturalists (ASN) and the Society of Systematic Biologists (SSB) sent a declaration addressed to President Trump and all the members of Congress. Implicitly claiming that its sentiments were endorsed by the 3500 members of the societies, the declaration also claimed that there is a scientific consensus on the definition of sex, and that is that sex is NOT binary but rather some unspecified but multivariate combination of different traits, a definition that makes sex a continuum or spectrum—and in all species! The bolding below is mine:
Scientific consensus defines sex in humans as a biological construct that relies on a combination of chromosomes, hormonal balances, and the resulting expression of gonads, external genitalia and secondary sex characteristics. There is variation in all these biological attributes that make up sex. Accordingly, sex (and gendered expression) is not a binary trait. While some aspects of sex are bimodal, variation along the continuum of male to female is well documented in humans through hundreds of scientific articles. Such variation is observed at both the genetic level and at the individual level (including hormone levels, secondary sexual characteristics, as well as genital morphology). Beyond the incorrect claim that science backs up a simple binary definition of sex, the lived experience of people clearly demonstrates that the genetic composition at conception does not define one’s identity. Rather, sex and gender result from the interplay of genetics and environment. Such diversity is a hallmark of biological species, including humans.
A number of biologists I talked to had strong objections to both this wonky declaration, which of course is based not on biology but on ideology (see my posts here and here), as well as to its implication that biologists, including members of the three societies, generally agreed with it. But the societies did not poll their members before issuing a general statement in their name!
The statement is in fact is a prime but embarrassing example of societies being ideologically captured to the extent that they misrepresent science to cater to “progressive” liberalism. The object of course is not foxes, horses, or oak trees, but humans; this is meant to reassure people who feel that they are “nonbinary” in gender that nature is just like them. (For an excellent analysis of the issue, and a defense of the binary nature of sex, see Richard Dawkins’s article here.)
Luana Maroja of Williams College, my frequent partner in crime, was even more concerned, and so she penned a letter which she sent last night to the Presidents of the three societies. With a little help from me, she managed to get 23 biologists to sign the letter (as expected, many demurred and wouldn’t sign). I reproduce Luana’s letter below with permission; Except for Luana and me, I have left off the signers’ names because I didn’t ask them if they wanted to go public about such a touchy subject.
To wit:
Dear presidents of the Tri-societies: ASN, SSB and SSE,
We, Tri-society members and/or biologists, are deeply disappointed by your recent letter “Letter to the US President and Congress on the Scientific Understanding of Sex and Gender” issued last Wednesday, Feb 5, 2025, in response to Trump’s executive order “Defending Women From Gender Ideology Extremism And Restoring Biological Truth To The Federal Government”.
While we agree that Trump’s executive orders are misleading, we disagree with your statements about the sex binary and its definition. In animals and plants, binary sex is universally defined by gamete type, even though sexes vary in how they are developmentally determined and phenotypically identified across taxa. Thus, your letter misrepresents the scientific understanding of many members of the Tri-societies.
You state that: “Scientific consensus defines sex in humans as a biological construct that relies on a combination of chromosomes, hormonal balances, and the resulting expression of gonads, external genitalia, and secondary sex characteristics.”
However, we do not see sex as a “construct” and we do not see other mentioned human-specific characteristics, such as “lived experiences” or “[phenotypic] variation along the continuum of male to female”, as having anything to do with the biological definition of sex. While we humans might be unique in having gender identities and certain types of sexual dimorphism, sex applies to us just as it applies to dragonflies, butterflies, or fish – there is no human exceptionalism. Yes, there are developmental pathologies that cause sterility and there are variations in phenotypic traits related to sexual dimorphism. However, the existence of this variation does not make sex any less binary or more complex, because what defines sex is not a combination of chromosomes or hormonal balances or external genitalia and secondary sex characteristics. The universal biological definition of sex is gamete size.
If you and the signers of this letter do not agree on these points, then the Tri-societies were wrong to speak in our names and claim that there is a scientific consensus without even conducting a survey of society members to see if such a consensus exists. Distorting reality to comply with ideology and using a misleading claim of consensus to give a veneer of scientific authority to your statement does more harm than just misrepresenting our views: it also weakens public trust in science, which has declined rapidly in the last few years. Because of this, scientific societies should stay away from politics as much as possible, except for political issues that directly affect the mission of the society.
Respectfully,
Jerry Coyne, Professor Emeritus, Ecology and Evolution, University of Chicago
Luana S. Maroja, Professor of Biology, Williams College
THE NAMES OF 21 OTHER SIGNERS ARE REDACTED
I doubt the Societies will pay this letter any attention, as they seem to be doubling down on the sex-is-a-spectrum-in-all-species view. This is performative flaunting of virtue that will accomplish nothing. But we and the other signers want the public to know that this view of biological sex is not held by all biologists, and hardly represents a scientific consensus. (If there is a consensus, it is most likely the gametic definition described by Dawkins.) If you want to write your own letter rather than sign a group effort, the email addressed of two Presidents are given in their letter, and it’s easy to google that of the ASN President. And if you did sign the letter and want that to be public, simply say it in the comments below.
As a former President of the SSE, I am ashamed of what that society has done, and they should be ashamed of themselves for truckling to the latest ideology. They can of course issue statements bearing on issues of evolution, but this one simply distorts the facts. And, as I reported yesterday, the SSE has seen fit to make more general declarations about politics.