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Ultra-Short-Period Sub-Neptune Found Orbiting TOI-1634 | Astronomy – Sci-News.com

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Using data from NASA’s Transiting Exoplanet Survey Satellite (TESS) and the HARPS-N spectrograph at the 3.6-m Telescopio Nazionale Galileo, astronomers have discovered and confirmed an ultra-short period keystone planet orbiting an M2 dwarf (red dwarf star) called TOI-1634.

An artist’s impression of the ultra-short-period sub-Neptune exoplanet TOI-1634b. Image credit: Sci-News.com.

An artist’s impression of the ultra-short-period sub-Neptune exoplanet TOI-1634b. Image credit: Sci-News.com.

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“Since its science operations began in July 2018, TESS has uncovered a wealth of transiting planet candidates whose orbital periods and radii lie within the radius valley, including three planets transiting early M-dwarfs: TOI-1235b, TOI-776b, and TOI-1685b,” said Dr. Ryan Cloutier from the Harvard & Smithsonian Center for Astrophysics and his colleagues.

“Radius valley planets, which we refer to as keystone planets, are valuable targets to conduct tests of the competing radius valley emergence models across a range of stellar masses.”

“Doing so requires that we characterize the bulk compositions of a sample of keystone planets using precise radial velocity measurements.”

“We present the confirmation and characterization of one such keystone planet from TESS: TOI-1634b,” they said.

TOI-1634b is a sub-Neptune planet with a radius of 1.8 times that of Earth and a mass of 4.8 Earth masses.

“The mass and radius of TOI-1634b are inconsistent with an Earth-like composition,” the astronomers noted.

The alien world has an orbital period of 1 day and lies 0.015 AU (astronomical units) from its host star, the M2 dwarf TOI-1634.

Also known as TIC 201186294 or 2MASS J03453363+3706438, the system is located 115 light-years away in the constellation of Perseus.

“The bulk composition of TOI-1634b is inconsistent with models of thermally-driven mass loss (i.e. photoevaporation and core-powered mass loss) and with gas-poor formation,” the researchers said.

“Instead, TOI-1634b favors the gas-depleted formation model and suggests that this formation mechanism may start to dominate the close-in planet population around M dwarfs with masses equal or less than 0.5 solar masses.”

“Emission spectroscopy observations will help to establish the chemical and physical properties that make the atmosphere of TOI-1634b resistant to hydrodynamic escape,” they added.

“Atmospheric models of solar composition, water-dominated, and carbon dioxide-dominated may be distinguished with 2-5 eclipse observations with instruments on the upcoming James Webb Space Telescope.”

A paper on the findings will be published in one of the AAS journals.

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R. Cloutier et al. 2021. TOI-1634b: an Ultra-Short Period Keystone Planet Sitting Inside the M Dwarf Radius Valley. AAS journals, submitted for publication; arXiv: 2103.12790

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Scientists claim evidence of 'Planet 9' in our solar system – Supercar Blondie

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A team of scientists claims to have evidence that there is another hidden planet – nicknamed ‘Planet 9’ – lurking in our solar system.

Of course, there have been changes to the number of planets in our solar system over recent – in space terms, anyway – years, as Pluto is no longer considered a proper planet.

Seems a bit harsh, doesn’t it?

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However, a team of astronomers now believe that they have the strongest evidence yet that there is another mysterious planet hovering around our sun.

READ MORE! James Webb Telescope observes light on Earth-like planet for the first time in history

The theory that there could be other planets orbiting our star has been around for years, as scientists have noticed some unusual phenomena on the edge of the solar system that suggest the existence of another celestial body.

The theory that another planet is responsible would also explain the orbit of other objects that are outliers in our system, sitting more than 250 times Earth’s distance from the sun.

Scientist Konstantin Bogytin and his team have long been proponents of this ‘Planet 9’ theory, and now they believe they have ‘the strongest statistical evidence yet that Planet 9 is really out there’.

As we know, it wouldn’t be the only strange thing in our solar system.

Or outside, for that matter.

Perhaps they just need to point a massive space telescope at it and they’ll find evidence of alien life out there.

This new study by Bogytin and his team focused on a number of Trans-Neptunian Objects (TNOs) that lie outside the orbit of Neptune towards the outer reaches of our solar system.

In analyzing the movements of these objects – which can be affected by the orbit of Neptune, as well as passing stars and the ‘galactic tide’ – the scientists concluded that there could be another unseen planet out there.

Dr Bogytin pointed out that there are other potential explanations for the behavior of these objects, but – he believes – Planet 9 is the best bet.

Once the Vera C. Rubin Observatory in Chile becomes active, we might get the best look we’ve had yet.

In a paper, the team wrote: “This upcoming phase of exploration promises to provide critical insights into the mysteries of our solar system’s outer reaches.”

That paper, entitled ‘Generation of Low-Inclination, Neptune-Crossing TNOs by Planet Nine’ is available to read here.

Images in this article were generated using AI

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Marine plankton could act as alert in mass extinction event: UVic researcher – Saanich News

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A University of Victoria micropaleontologist found that marine plankton may act as an early alert system before a mass extinction occurs.

With help from collaborators at the University of Bristol and Harvard, Andy Fraass’ newest paper in the Nature journal shows that after an analysis of fossil records showed that plankton community structures change before a mass extinction event.

“One of the major findings of the paper was how communities respond to climate events in the past depends on the previous climate,” Fraass said in a news release. “That means that we need to spend a lot more effort understanding recent communities, prior to industrialization. We need to work out what community structure looked like before human-caused climate change, and what has happened since, to do a better job at predicting what will happen in the future.”

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According to the release, the fossil record is the most complete and extensive archive of biological changes available to science and by applying advanced computational analyses to the archive, researchers were able to detail the global community structure of the oceans dating back millions of years.

A key finding of the study was that during the “early eocene climatic optimum,” a geological era with sustained high global temperatures equivalent to today’s worst case global warming scenarios, marine plankton communities moved to higher latitudes and only the most specialized plankton remained near the equator, suggesting that the tropical temperatures prevented higher amounts of biodiversity.

“Considering that three billion people live in the tropics, the lack of biodiversity at higher temperatures is not great news,” paper co-leader Adam Woodhouse said in the release.

Next, the team plans to apply similar research methods to other marine plankton groups.

Read More: Global study, UVic researcher analyze how mammals responded during pandemic

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The largest marine reptile ever could match blue whales in size – Ars Technica

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Blue whales have been considered the largest creatures to ever live on Earth. With a maximum length of nearly 30 meters and weighing nearly 200 tons, they are the all-time undisputed heavyweight champions of the animal kingdom.

Now, digging on a beach in Somerset, UK, a team of British paleontologists found the remains of an ichthyosaur, a marine reptile that could give the whales some competition. “It is quite remarkable to think that gigantic, blue-whale-sized ichthyosaurs were swimming in the oceans around what was the UK during the Triassic Period,” said Dean Lomax, a paleontologist at the University of Manchester who led the study.

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Giant jawbones

Ichthyosaurs were found in the seas through much of the Mesozoic era, appearing as early as 250 million years ago. They had four limbs that looked like paddles, vertical tail fins that extended downward in most species, and generally looked like large, reptilian dolphins with elongated narrow jaws lined with teeth. And some of them were really huge. The largest ichthyosaur skeleton so far was found in British Columbia, Canada, measured 21 meters, and belonged to a particularly massive ichthyosaur called Shonisaurus sikanniensis. But it seems they could get even larger than that.

What Lomax’s team found in Somerset was a surangular, a long, curved bone that all reptiles have at the top of the lower jaw, behind the teeth. The bone measured 2.3 meters—compared to the surangular found in the Shonisaurus sikanniensis skeleton, it was 25 percent larger. Using simple scaling and assuming the same body proportions, Lomax’s team estimated the size of this newly found ichthyosaur at somewhere between 22 and 26 meters, which would make it the largest marine reptile ever. But there was one more thing.

Examining the surangular, the team did not find signs of the external fundamental system (EFS), which is a band of tissue present in the outermost cortex of the bone. Its formation marks a slowdown in bone growth, indicating skeletal maturity. In other words, the giant ichthyosaur was most likely young and still growing when it died.

Correcting the past

In 1846, five large bones were found at the Aust Cliff near Bristol in southwestern England. Dug out from the upper Triassic rock formation, they were dubbed “dinosaurian limb bone shafts” and were exhibited in the Bristol Museum, where one of them was destroyed by bombing during World War II.

But in 2005, Peter M. Galton, a British paleontologist then working at the University of Bridgeport, noticed something strange in one of the remaining Aust Cliff bones. He described it as an “unusual foramen” and suggested it was a nutrient passage. Later studies generally kept attributing those bones to dinosaurs but pointed out things like an unusual microstructure that was difficult to explain.

According to Lomax, all this confusion was because the Aust Cliff bones did not belong to dinosaurs and were not parts of limbs. He pointed out that the nutrient foramen morphology, shape, and microstructure matched with the ichthyosaur’s bone found in Somerset. The difference was that the EFS—the mark of mature bones—was present on the Aust Cliff bones. If Lomax is correct and they really were parts of ichthyosaurs’ surangular, they belonged to a grown individual.

And using the same scaling technique applied to the Somerset surangular, Lomax estimated this grown individual to be over 30 meters long—slightly larger than the biggest confirmed blue whale.

Looming extinction

“Late Triassic ichthyosaurs likely reached the known biological limits of vertebrates in terms of size. So much about these giants is still shrouded by mystery, but one fossil at a time, we will be able to unravel their secrets,” said Marcello Perillo, a member of the Lomax team responsible for examining the internal structure of the bones.

This mystery beast didn’t last long, though. The surangular bone found in Somerset was buried just beneath a layer full of seismite and tsunamite rocks that indicate the onset of the end-Triassic mass extinction event, one of the five mass extinctions in Earth’s history. The Ichthyotian severnensis, as Lomax and his team named the species, probably managed to reach an unbelievable size but was wiped out soon after.

The end-Triassic mass extinction was not the end of all ichthyosaurs, though. They survived but never reached similar sizes again. They faced competition from plesiosaurs and sharks that were more agile and swam much faster, and they likely competed for the same habitats and food sources. The last known ichthyosaurs went extinct roughly 90 million years ago.

PLOS ONE, 2024.  DOI: 10.1371/journal.pone.0300289

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