Category: 7. Science

In the era of photometry with space-based telescopes, such as CHEOPS (CHaracterizing ExOPlanets Satellite), JWST (James Webb Space Telescope), PLATO (PLAnetary Transits and Oscillations of stars), and ARIEL (Atmospheric Remote-sensing Infrared Exoplanet Large-survey), the road has opened for detecting subtle distortions in exoplanet transit light curves — resulting from their non-spherical shape.

We investigate the prospects of retrieval of rotational flatness (oblateness) of exoplanets at various noise levels. We present a novel method for calculating the transit light curves based on the Gauss-Legendre quadrature. We compare it in the non-rotating limit to the available analytical models.

We conduct injection-and-retrieval tests to assess the precision and accuracy of the retrievable oblateness values. We find that the light curve calculation technique is about 25% faster than a well-known analytical counterpart, while still being precise enough.

We show that a 3σ oblateness detection is possible for a planet orbiting bright enough stars, by exploiting a precise estimate on the stellar density obtained e.g. from asteroseismology. We also show that for noise levels ≥256 ppm (expressed as point-to-point scatter with a 60~s exposure time) detection of planetary oblateness is not reliable.

Sz. Kálmán, Sz. Csizmadia, L. M. Bernabó, R. Szabó, Gy. M. Szabó

Comments: Provisionally accepted for publication in PASP on 18/07/2025. 23 pages, 17 figures
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2507.15359 [astro-ph.EP] (or arXiv:2507.15359v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2507.15359
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Submission history
From: Szilárd Kálmán
[v1] Mon, 21 Jul 2025 08:10:49 UTC (2,197 KB)
https://arxiv.org/abs/2507.15359
Astrobiology, exoplanet,

For hungry Neanderthals, there was more on the menu than wild mammals, roasted pigeon, seafood and plants. Chemical signatures in the ancient bones point to a nutritious and somewhat inevitable side dish: handfuls of fresh maggots.

The theory from US researchers undermines previous thinking that Neanderthals were “hypercarnivores” who stood at the top of the food chain with cave lions, sabre-toothed tigers and other beasts that consumed impressive quantities of meat.

Rather than feasting on endless mammoth steaks, they stored their kills for months, the scientists believe, favouring the fatty parts over lean meat, and the maggots that riddled the putrefying carcasses.

“Neanderthals were not hypercarnivores, their diet was different,” said John Speth, professor emeritus of anthropology at the University of Michigan. “It’s likely maggots were a major food.”

Neanderthals were thought to be top of the food chain because of the high levels of heavy nitrogen in their bones. Nitrogen builds up in living organisms when they metabolise protein in their food. A lighter form of the element, nitrogen-14, is excreted more readily than the heavier form, nitrogen-15. As a result, heavy nitrogen builds up in organisms with each step up the food chain, from plants to herbivores to carnivores.

While the levels of heavy nitrogen in Neanderthal bones place them at the top of the food chain, they would not have been able to handle the amount of meat needed to reach those levels, the researchers say.

“Humans can only tolerate up to about 4 grams of protein per kilogram of body weight, whereas animals like lions can tolerate anywhere from two to four times that much protein safely,” said Speth.

Since many Indigenous groups around the world routinely consume maggots in putrefied meat, the researchers decided to explore their potential role. The experiments were not for the squeamish.

Dr Melanie Beasley, a member of the team at Purdue University in Indiana, was formerly at the Forensic Anthropology Center, or Body Farm, at the University of Tennessee. There, researchers study donated human corpses that are left to decompose. The work helps forensic scientists hone their techniques, for example, to ascertain for how long people have been dead.

Beasley measured heavy nitrogen in putrefying muscle and the maggots that infested the corpses. Heavy nitrogen rose slightly as muscle putrefied, but was far higher in the maggots. The same process would have occurred in carcasses the Neanderthals stored, Beasley said.

The finding, reported in Science Advances, suggests that rather than consuming meat as ravenously as lions and other hypercarnivores, Neanderthals acquired high levels of heavy nitrogen by eating maggots, which themselves were enriched with heavy nitrogen.

“The only reason this is surprising is that it contradicts what we westerners think of as food,” said Karen Hardy, professor of prehistoric archaeology at the University of Glasgow. “Elsewhere in the world, a very wide range of things are eaten, and maggots are a great source of protein, fat and essential amino acids.”

“It is a no brainer for Neanderthals,” she added. “Put out a bit of meat, leave it for a few days then go back and harvest your maggots, its a very easy way to get good nutritious food.”

“How does it shift our thinking? The Neanderthals as top carnivores was nonsense, it was physiologically impossible. So this makes sense, but also explains these high nitrogen signals in a way that nothing else has done so clearly,” Hardy said.

After almost 15 years, the influential scholarly journal Science has retracted a controversial paper about the discovery of a microbe able to use arsenic instead of phosphorous in its biochemical processes (Science 2010, DOI: 10.1126/science.1197258).

In the retraction notice, H. Holden Thorp, Science’s editor in chief since 2019, states that the paper is being retracted on the basis that the “reported experiments do not support its key conclusions” but not because of any deliberate fraud or misconduct.

The retraction is accompanied by a letter from the authors disagreeing with the decision, stating, “While our work could have been written and discussed more carefully, we stand by the data as reported.”

In the original paper, the authors describe an extremophile microbe called GFAJ-1 that they believe has the ability to weave arsenic into its proteins and nucleic acids to compensate for a lack of phosphorus. Confirming that arsenic can be incorporated into DNA has the potential to expand the chemical understanding of life on Earth—and beyond, an aspect that NASA and the journal initially played up.

The paper immediately garnered harsh criticism from the scientific community over the researchers’ methods and conclusions. In 2012, Science published two papers from independent teams who were unable to replicate the original paper’s results.

The current consensus is that although GFAJ-1 is unusually good at growing in high concentrations of toxic arsenic, sufficient evidence hasn’t been found that it actually incorporates arsenic into its DNA, and the bacterium likely survives by scavenging trace phosphorus from its surroundings. The authors say in their letter that these follow-ups didn’t adequately reproduce their original growth conditions for GFAJ-1.

Back in 2012, Science’s policy was to retract papers only in cases of misconduct, which this is not. But, Thorp says, “The expectations for straightening out the literature have risen significantly,” and calls for the paper to be retracted have simmered throughout his tenure at the journal.

The tipping point was a New York Times profile of Felisa Wolfe-Simon, the paper’s outspoken first author, that was published in February 2025. Thorp went on the record in that article saying he thought the paper should be retracted.

According to guidelines from the Committee on Publication Ethics (COPE), “Retraction is a mechanism for correcting the literature and alerting readers to articles that contain such seriously flawed or erroneous content or data that their findings and conclusions cannot be relied upon. Unreliable content or data may result from honest error, naïve mistakes, or research misconduct.”

Science’s current retraction policy states, “An accumulation of errors identified in a paper may cause the editors to lose confidence in the integrity of the data presentation, and the paper may be retracted.”

Ariel Anbar of Arizona State University, one of the original paper’s authors, says the uncertainty in the data is “larger than one would like,” but “we don’t think there was a major error” that warrants retraction.

Anbar says Thorp asked Wolfe-Simon to voluntarily retract the paper last fall, after he was contacted by the New York Times. She refused. After months of negotiations, the researchers and journal editors reached a compromise: The paper would be retracted with language that both parties agreed on. The researchers could voice their dissent in a letter.

In addition to posting the retraction notice, Thorp and Science’s executive editor, Valda Vinson, published a blog post in which they expand on their reasons for retracting the paper. In the post, they reiterate that the decision is rooted in experimental error and “at no point has there been any discussion or suggestion at Science of research misconduct or fraud by any of the authors.”

Thorp says he hopes that retracting the paper will put a period on the whole affair. “I hope this is the end of it,” he says.

Anbar says he and his coauthors asked to see the blog post ahead of time, and the journal didn’t respond; they received a copy from a reporter. The post brings up critiques beyond what went into the notice, which Anbar says undermines the good-faith commitment to transparency that the authors and editors made when negotiating the retraction.

One thing both Anbar and Thorp appear to agree on—although for different reasons—is wishing that arsenic life hadn’t whipped up such a firestorm in the first place.

Astronomers have discovered key components to life’s building blocks swirling around a remote baby star, hinting that the stuff of life is far more prevalent throughout the universe than once thought.

The material, discovered circling the protostar V883 Orionis 1,300 light-years from Earth in the constellation Orion, consists of 17 complex organic molecules that include ethylene glycol and glycolonitrile — precursors to components found in DNA and RNA.

On July 02, 2025, astronomers confirmed the discovery of Comet 3I/ATLAS, marking only the third time in recorded history that an interstellar object (ISO) has been identified passing through our Solar System. This follows the landmark discoveries of 1I/‘Oumuamua in 2017 and 2I/Borisov in 2019.

The confirmation was discussed during a SETI Live broadcast hosted by Dr. Simon Steel, Deputy Director of the Carl Sagan Center at the SETI Institute, and featured expert commentary from University of Washington astronomer Dr. James Davenport, SETI Institute postdoctoral fellow and comet researcher Dr. Ariel Graykowski, and SETI Chair and Allen Telescope Array Project Scientist Dr. Wael Farah.

Discovery by the ATLAS Survey

Comet 3I/ATLAS was first identified by the Asteroid Terrestrial-impact Last Alert System (ATLAS), a global network of four robotic telescopes located in Hawaii, Chile, and South Africa. ATLAS systematically surveys nearly the entire night sky every 24 hours, primarily searching for near-Earth objects that could pose a risk of impact.

Initially, 3I/ATLAS appeared as a faint, fast-moving point of light. However, follow-up observations revealed the object was traveling at a hyperbolic velocity, meaning its speed and trajectory exceeded the Sun’s gravitational binding energy. This is characteristic of interstellar objects on open-ended orbits, distinguishing them from the typical elliptical orbits of bodies in the Solar System.

Cometary Activity Detected: A Distinctive Feature

Unlike 1I/‘Oumuamua, which lacked any visible comet-like features, 3I/ATLAS has displayed clear cometary activity, even while still four astronomical units (AU) from the Sun (one AU is the average distance between Earth and the Sun), making 3I/ATLAS more similar to 2I/Borisov in that regard.

According to Dr. Graykowski, this activity manifests as a coma: a diffuse envelope of gas and dust created by the sublimation (transition from solid to gas) of volatile compounds. The early onset of sublimation indicates the presence of highly volatile ices, potentially providing a pristine record of the object’s origin outside the Solar System.

Dr. Davenport emphasized that 3I/ATLAS is moving faster than either of the previous interstellar visitors at roughly 60 m/s, suggesting it was ejected from its parent stellar system with substantial kinetic energy, possibly due to gravitational interactions with massive planetary bodies or close stellar encounters.

Multi-Wavelength Observations in Progress

Optical Monitoring Through Citizen Science

Dr. Graykowski leads optical monitoring efforts using the UNISTELLAR Network, a decentralized array of small, smart telescopes operated by citizen scientists worldwide. Despite the object’s faintness, UNISTELLAR telescopes (with apertures of just 3-4.5 inches) have successfully detected it using image stacking techniques to compensate for the comet’s rapid motion.

Early brightness measurements reveal a steep increase in luminosity, which is consistent with dynamic new comets making their first close approach to a star. This rapid brightening reflects the sublimation of volatile compounds that have remained unaltered since their formation, offering a unique opportunity to probe primordial interstellar materials.

Radio Observations at the Allen Telescope Array

Radio observations began promptly at the SETI Institute’s Allen Telescope Array (ATA), led by Dr. Wael Farah. The ATA team initiated monitoring on the night of July 2, targeting both narrowband emissions (a potential indicator of artificial (technological) signals) and natural emissions such as continuum radiation from dust and specific spectral lines associated with common molecules like hydroxyl (OH).

Within just a week, the ATA had amassed over 21 terabytes of data, equivalent to thousands of hours of high-resolution video. This dataset is under active analysis, with researchers scouring the data for both natural radio signatures and hypothetical technosignatures.

Prospects for Spectroscopic Analysis

Future observations from large facilities, including the Vera C. Rubin Observatory, will enable detailed spectroscopic studies, which are a technique used to decipher the chemical composition of astronomical objects. Spectroscopy will allow scientists to determine whether 3I/ATLAS harbors exotic compounds not commonly found in Solar System comets.

Media accreditation is open for the next launch to deliver NASA science investigations, supplies, and equipment to the International Space Station. This launch is the 33rd SpaceX commercial resupply services mission to the orbital laboratory for NASA and will liftoff on the company’s Falcon 9 rocket.

NASA and SpaceX are targeting no earlier than Thursday, Aug. 21, to launch the SpaceX Dragon spacecraft from Space Launch Complex-40 at Cape Canaveral Space Force Station in Florida.

Credentialing to cover prelaunch and launch activities is open to U.S. media. The application deadline for U.S. citizens is 11:59 p.m. EDT, Sunday, Aug. 3. All accreditation requests must be submitted online at:

https://media.ksc.nasa.gov

Credentialed media will receive a confirmation email upon approval. NASA’s media accreditation policy is available online. For questions about accreditation, or to request special logistical support, email: ksc-media-accreditat@mail.nasa.gov. For other questions, please contact NASA’s Kennedy Space Center newsroom at: 321-867-2468.

Para obtener información sobre cobertura en español en el Centro Espacial Kennedy o si desea solicitor entrevistas en español, comuníquese con Antonia Jaramillo o Messod Bendayan a: antonia.jaramillobotero@nasa.gov o messod.c.bendayan@nasa.gov.

Each resupply mission to the station delivers scientific investigations in the areas of biology and biotechnology, Earth and space science, physical sciences, and technology development and demonstrations. Cargo resupply from U.S. companies ensures a national capability to deliver scientific research to the space station, significantly increasing NASA’s ability to conduct new investigations aboard humanity’s laboratory in space.

In addition to food, supplies, and equipment for the crew, Dragon will deliver several new experiments, including bone-forming stem cells for studying bone loss prevention and materials to 3D print medical implants that could advance treatments for nerve damage on Earth. Dragon also delivers bioprinted liver tissue to study blood vessel development in microgravity and supplies to 3D print metal cubes in space.

For almost 25 years, humans have continuously lived and worked aboard the International Space Station, advancing scientific knowledge and demonstrating new technologies that enable us to prepare for human exploration of the Moon as we prepare for Mars.

Learn more about NASA’s commercial resupply missions at:

https://www.nasa.gov/station

-end-

Claire O’Shea
Headquarters, Washington
202-358-1100
claire.a.o’shea@nasa.gov

Stephanie Plucinsky / Steven Siceloff / Danielle Sempsrott
Kennedy Space Center, Fla.
321-876-2468
stephanie.n.plucinsky@nasa.gov / steven.p.siceloff@nasa.gov / danielle.c.sempsrott@nasa.gov

Sandra Jones
Johnson Space Center, Houston
281-483-5111
sandra.p.jones@nasa.gov