Exoplanets – worlds of other suns

[wjfox]

Scientists spot candidate for speediest exoplanet system
https://phys.org/news/2025-02-scientist ... lanet.html
by Ashley Balzer, NASA

Astronomers may have discovered a scrawny star bolting through the middle of our galaxy with a planet in tow. If confirmed, the pair sets a new record for the fastest-moving exoplanet system, nearly double our solar system's speed through the Milky Way.

The planetary system is thought to move at least 1.2 million miles per hour, or 540 kilometers per second.

"We think this is a so-called super-Neptune world orbiting a low-mass star at a distance that would lie between the orbits of Venus and Earth if it were in our solar system," said Sean Terry, a postdoctoral researcher at the University of Maryland, College Park and NASA's Goddard Space Flight Center in Greenbelt, Maryland. Since the star is so feeble, that's well outside its habitable zone. "If so, it will be the first planet ever found orbiting a hypervelocity star."

540 km/s is almost identical to the escape velocity you'd need to leave the Milky Way.

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First 3D observations of an exoplanet's atmosphere reveal a unique climate
https://phys.org/news/2025-02-3d-exopla ... nique.html
by ESO

Astronomers have peered through the atmosphere of a planet beyond the solar system, mapping its 3D structure for the first time. By combining all four telescope units of the European Southern Observatory's Very Large Telescope (ESO's VLT), they found powerful winds carrying chemical elements like iron and titanium, creating intricate weather patterns across the planet's atmosphere.

The discovery opens the door for detailed studies of the chemical makeup and weather of other alien worlds.

"This planet's atmosphere behaves in ways that challenge our understanding of how weather works—not just on Earth, but on all planets. It feels like something out of science fiction," says Julia Victoria Seidel, a researcher at the European Southern Observatory (ESO) in Chile and lead author of the study, published in Nature.

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JWST uncovers rare ultra-hot Neptune LTT 9779 b's exotic atmosphere
https://phys.org/news/2025-02-jwst-unco ... a-hot.html
by University of Oxford

A team of international researchers including Dr. Jake Taylor from the Department of Physics at the University of Oxford, has used the James Webb Space Telescope (JWST) to explore the exotic atmosphere of LTT 9779 b, a rare "ultra-hot Neptune." The results are published on 25 February in Nature Astronomy.

The study offers new insights into the extreme weather patterns and atmospheric properties of this fascinating exoplanet, LTT 9779 b, that resides in the so-called hot Neptune desert, a category of planets where exceptionally few are known to exist. While giant planets orbiting very close to their host stars—often called hot Jupiters—are commonly detected using current exoplanet-finding methods, ultra-hot Neptunes like LTT 9779 b remain remarkably rare.

[caltrek]

Extraterrestrial Life: Astronomers Detect Something Unusual on a Distant Planet
by Gisselle Acevedo
February 27, 2025

Introduction:

(MSN) In a groundbreaking moment for astronomy, scientists have detected a coherent radio signal from a distant planet, reigniting hopes of finding extraterrestrial life. This discovery, made using a radio telescope, suggests that the planet, named 'YZ Ceti b', might have a magnetic field similar to Earth's. The signal, originating from 70.5 trillion miles away, has captured the scientific community's attention, offering potential insights into the universe's mysteries

YZ Ceti b, an Earth-sized planet, orbits a red dwarf star called YZ Ceti. Astronomers speculate that the detected radio waves could result from interactions between the exoplanet's magnetic field and its host star. This phenomenon is akin to what happens on Earth, where the Northern Lights are the result of interactions between the magnetic field and solar weather. Observing this phenomenon on distant planets is an exciting step forward in the quest for life beyond our solar system.

The discovery of YZ Ceti b is a crucial step in identifying planets with magnetic fields, which could be vital for a planet's habitability. Magnetic fields are essential to prevent atmospheric erosion caused by stellar emissions, allowing a planet to retain its atmosphere over time. This finding not only opens new possibilities for space exploration but also offers a future technique for discovering more planets with similar characteristics.

Dr. Sebastián Pineda and Jackie Villadsen, who led the study, used the Karl G. Jansky Very Large Array to detect the radio signal. This radio telescope, managed by the National Radio Astronomy Observatory of the National Science Foundation in the United States, has been crucial in gaining deeper insights into the magnetic dynamics between distant stars and their planets. The research, published in Nature Astronomy, has been hailed as a significant advancement in the study of exoplanets.

Read more here: https://www.msn.com/en-us/news/technol ... 625&ei=39

[firestar464]

Apparently this is old news

https://telescope.live/blog/powerful-ra ... etic-field

[caltrek]

Beyond Our Solar System: Scientists Identify a New Exoplanet Candidate
March 4, 2025

Introduction:

(Eurekalert) Scientists from UNSW Sydney have located a potential new exoplanet – a planet that orbits a star outside of our solar system – using a technique known as ‘transit timing variation’.

In research highlighted in a new paper, published today in The Astrophysical Journal, Scientia Senior Lecturer Ben Montet and PhD candidate Brendan McKee analysed changes in the timing of a known planet’s transit across its star, to infer the presence of a second exoplanet.

After identifying an unusual trend in the movement of the hot Jupiter planet TOI-2818b, the team, from the UNSW School of Physics, ran a series of model simulations that pointed to the presence of a small planetary companion to the known hot Jupiter.

The new exoplanet is estimated to be 10-16 times the size of Earth, with a predicted orbital period less than 16 days.

"It’s rare for hot Jupiters to have other planets near them,” says Dr Montet. “So this new planet could have implications about how hot Jupiters form and in turn, help us to understand other solar systems.”

Read more here: https://www.eurekalert.org/news-releases/1075784

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The Magnetically Induced Radial Velocity Variation of Gliese 341 and an Upper Limit to the Mass of Its Transiting Earth-sized Planet

https://arxiv.org/abs/2502.07867

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TOI-6324b: An Earth-Mass Ultra-Short-Period Planet Transiting a Nearby M Dwarf

https://arxiv.org/abs/2502.16087

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HADES RV Programme with HARPS-N at TNG
XVI. A super-Earth in the habitable zone of the GJ 3998 multi-planet system

https://doi.org/10.1051/0004-6361/202452630

[wjfox]

4 Rocky Worlds Found Orbiting Our Sun's Closest Single Star, And They're Tiny

13 March 2025

Astronomers have been looking for exoplanets orbiting Barnard's Star – the nearest solitary star to our Solar System, at just 5.96 light-years away – since its discovery in 1916.

Unconvincing signs of planets in the lonely star's orbit have been reported previously, but the search efforts have now finally paid off.

Following the announced discovery of a single candidate world in October of last year, a team led by Ritvik Basant of the University of Chicago has confirmed its presence along with another three – bringing the total number of known worlds around Barnard's star to four.

What makes the achievement even more spectacular is that all four exoplanets in the system are smaller than Earth, the hardest exoplanets to find amongst the wild variety identified in the Milky Way.

"It's a really exciting find – Barnard's Star is our cosmic neighbor, and yet we know so little about it," Basant says. "It's signaling a breakthrough with the precision of these new instruments from previous generations."

https://www.sciencealert.com/4-rocky-wo ... heyre-tiny

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Webb telescope directly observes exoplanet CO₂ for first time
https://phys.org/news/2025-03-webb-tele ... lanet.html
by Daniel Lawler
The Webb telescope as it left Earth in 2021.

The James Webb Space Telescope has directly observed the key chemical of carbon dioxide in planets outside of our solar system for the first time, scientists announced Monday.

The gas giants are not capable of hosting extraterrestrial life, but do offer clues in a lingering mystery about how distant planets form, according to a study in The Astrophysical Journal.

The HR 8799 system, 130 light years from Earth, is only 30 million years old—just a baby compared to our solar system's 4.6 billion years.

A U.S.-led team of researchers used Webb to directly detect carbon dioxide in the atmosphere of all four of the system's known planets, according to the study.

They used Webb's coronagraph instruments, which block the light from bright stars to get a better view of the planets revolving around them.

[wjfox]

This newly found super-Earth might have blown off its own atmosphere

March 31, 2025

A super-Earth that could explain the universe's mysterious lack of certain exoplanets has been found by NASA's Transiting Exoplanet Survey Satellite (TESS) and the planet-measuring ESPRESSO instrument on the Very Large Telescope in Chile.

"It's a small addition to the already long list of known planets, but such discoveries are essential to improve our understanding of the mechanisms of planet formation and evolution," said José Rodrigues of the Porto Institute of Astrophysics, who led the study, in a statement. "Many more [planets] will be needed to transform our hypotheses into scientific certainties."

The exoplanet, named TOI-512b, is located 218 light-years away. It was first identified by TESS in 2020, which saw the planet transit, or regularly move in front of, its star, blocking some of the star’s light from reaching our vantage point in the cosmos. Based on the amount of light blocked, astronomers measured TOI-512b's radius to be 1.54 times the size of Earth's.

[...]

TOI-512b orbits its star every 7.1 days at a distance of just 9,863,797 kilometers (6,129,079 miles). This means that it gets rather hot — it's too close to its star to be in the habitable zone, receiving 112 times as much heat from its star as Earth does. Its size also places it just below what researchers call the "hot Neptune desert."

Astronomers are finding exoplanets of myriad sizes and masses, but there seems to be a dramatic dearth of worlds between about 1.8 and 2.4 times the radius of Earth. This is the aforementioned desert, and one theory is that as Neptune-size worlds rich in gas and ice migrate inwards towards their star, stellar radiation blows their atmosphere away, removing much of the gas and leaving a smaller world at the end of the process.

https://www.yahoo.com/news/newly-found- ... 00061.html

[caltrek]

How Many Rogue Planets Roam the Milky Way?
by Phil Plait
April 4, 2025

Introduction:

(Scientific America) As J.R.R. Tolkien wrote in The Fellowship of the Ring, “Not all those who wander are lost.” But in the case of planets, it’s possible that most of them are.

Rogue planets—planets that are adrift in space, unmoored from any star—have been a topic of science fiction for a long time; both Star Trek and Space:1999 featured them in episodes. But they actually do exist in real life. Astronomers, who sometimes like to kill fun, call these worlds free-floating planets, which is not nearly as cool a term.

Still, these interstellar drifters are pretty interesting. Most have been found via microlensing: their gravity acts as a lens that boosts the light of a background star in a measurable way. These worlds tend to be so small, dark and far away that they’re otherwise invisible to us. Some, similar to Jupiter in mass, have been glimpsed in images; these likely formed directly from the gas and dust in a nebula, much as a star does, and may have thus always lacked a home star. But others, much lower in mass, are expected to have formed around a star only to subsequently be ejected from their planetary system. Now these outcasts slip silent and cold through the sunless spaces between the stars.

How are they ejected? While there are a handful of possible methods, the most common is likely via interactions with another planet around its host star. We know that planets don’t just orbit their star in the same place forever. Over time, planetary orbits can shift because of the combined gravitational influences of other planets in a system. If two planets get too close to each other, the interaction can cause one (usually the less massive of the two) to gain a lot of orbital energy, causing it to be flung out of the system.

Still, these interstellar drifters are pretty interesting. Most have been found via microlensing: their gravity acts as a lens that boosts the light of a background star in a measurable way. These worlds tend to be so small, dark and far away that they’re otherwise invisible to us.

Read more here: https://www.scientificamerican.com/art ... lky-way/

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Hidden Transits: TOI-2285 b is a Warmer Sub-Neptune Likely with a Super-Earth Companion

https://iopscience.iop.org/article/10.3 ... 172/adc7fb

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The CARMENES search for exoplanets around M dwarfs. Occurrence rates of Earth-like planets around very low-mass stars

https://arxiv.org/abs/2504.03364

4 new planets GJ 1028b, GJ 1238b and GJ 3380b and c

[wjfox]

New sub-Neptune exoplanet orbiting nearby star detected

April 14, 2025

Using the radial velocity method, an international team of astronomers has discovered a new extrasolar planet orbiting a nearby star known as GI 410. The newfound alien world was classified as a sub-Neptune exoplanet with a mass of at least 8.4 Earth masses. The discovery was reported April 4 on the pre-print server arXiv.

The radial velocity (RV) method of detecting an exoplanet is based on the detection of variations in the velocity of the central star, due to the changing direction of the gravitational pull from an unseen exoplanet as it orbits the star. Thanks to this technique, more than 600 exoplanets have been detected so far.

[...]

The newly detected planet, which received designation GI 410 b, has a minimum mass of 8.4 Earth masses and orbits its host every 6.02 days, at a distance of some 0.053 AU from it. However, given that GI 410 b does not transit its parent star, its radius still remains unknown.

The host star GI 410, which is located about 39 light years away, is about half the size and mass of the sun. The star has an effective temperature at a level of 3,842 K and its age was estimated to be 480 million years, therefore it is one of the youngest stars nearby.

[...]

Besides the detection of Gl 410 b, tentative evidence for two additional planetary signals was found at 2.99 and 18.7 days. However, further observations are required in order to confirm the planetary nature of these signals.

https://phys.org/news/2025-04-neptune-e ... -star.html

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Rare exoplanet orbits twin stars in 'Star Wars'-like twist
https://phys.org/news/2025-04-astronome ... -star.html
by University of Birmingham

Astronomers have discovered a planet that orbits at a 90-degree angle around a rare pair of strange stars—a real-life 'twist' on the fictional twin suns of Star Wars hero Luke Skywalker's home planet of Tatooine.

The exoplanet, named 2M1510 (AB) b, orbits a pair of young brown dwarfs—objects bigger than gas-giant planets but too small to be proper stars. Only the second pair of eclipsing brown dwarfs known—this is the first exoplanet found on a right-angled path to the orbit of its two host stars.

An international team of researchers led by the University of Birmingham made the surprise discovery using the European Southern Observatory's Very Large Telescope (VLT). The brown dwarfs produce eclipses of one another, as seen from Earth, making them part of an "eclipsing binary."

[caltrek]

Rare exoplanet orbits twin stars in 'Star Wars'-like twist
https://phys.org/news/2025-04-astronome ... -star.html
by University of Birmingham

[caltrek]

Astronomers Discover a Planet That’s Rapidly Disintegrating, Producing a Comet-like Tail
April 22, 2025

Introduction:

(Eurekalert) MIT astronomers have discovered a planet some 140 light-years from Earth that is rapidly crumbling to pieces.

The disintegrating world is about the mass of Mercury, although it circles about 20 times closer to its star than Mercury does to the sun, completing an orbit every 30.5 hours. At such close proximity to its star, the planet is likely covered in magma that is boiling off into space. As the roasting planet whizzes around its star, it is shedding an enormous amount of surface minerals and effectively evaporating away.

The astronomers spotted the planet using NASA’s Transiting Exoplanet Survey Satellite (TESS), an MIT-led mission that monitors the nearest stars for transits, or periodic dips in starlight that could be signs of orbiting exoplanets. The signal that tipped the astronomers off was a peculiar transit, with a dip that fluctuated in depth every orbit.

The scientists confirmed that the signal is of a tightly orbiting rocky planet that is trailing a long, comet-like tail of debris.

“The extent of the tail is gargantuan, stretching up to 9 million kilometers long, or roughly half of the planet’s entire orbit,” says Marc Hon, a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research.

Read more here: https://www.eurekalert.org/news-releases/1081038

Edit: Here is a Futuretimeline blog on this topic: https://www.futuretimeline.net/blog/202 ... years.htm