Tag Archives: orbiting

Exciting Discovery: Earth-Sized Exoplanet Found Orbiting Nearby Star

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Astronomers have recently identified a new exoplanet, HD 137010b, orbiting the nearby K dwarf star HD 137010, following the detection of a single shallow transit in archived data from NASA’s Kepler Expansion K2 mission.

HD 137010b is estimated to be 6% larger than Earth, with surface temperatures akin to those of Mars, possibly dipping below -70 degrees Celsius. Image credit: NASA/JPL-Caltech/Keith Miller, California Institute of Technology and IPAC.

HD 137010 is classified as a K3.5V dwarf star located approximately 146 light-years away in the constellation Libra.

This star’s age ranges between 4.8 billion and 10 billion years, and its low magnetic activity reflects its status as an old, relatively calm star.

Commonly referenced as BD-19 4097, HIC 75398, 2MASS J15242123-1944215, or TYC 6179-1111-1, HD 137010 has an apparent magnitude of 10.1 and is recognized as one of the brightest stars hosting an Earth-sized planet in temperate orbits.

The new exoplanet, designated HD 137010b, was observed during K2 Campaign 15 when NASA’s Kepler Space Telescope monitored its parent star for about three months in 2017.

“Most Earth-sized planets discovered in the habitable zone orbit red dwarfs, which are smaller and dimmer than the Sun,” explains lead author Astronomer Alexander Venner from the University of Southern Queensland.

“Concerns arise regarding these planets losing their atmospheres due to intense radiation from their host stars, rendering them uninhabitable for known life forms.”

“However, HD 137010b’s star shares characteristics more closely aligned with the Sun, increasing the likelihood that a stable atmosphere could be retained, according to current theoretical models.”

In their study, Venner and colleagues analyzed K2 data, light curves from nearby stars, archival images, and radial velocity measurements to clarify the nature of the transit signal, which lasted roughly 10 hours.

These evaluations strongly suggest that the observed transit is astrophysical and not a result of background interference, eclipsing binaries, or solar-system debris.

Astronomers have determined that the planet’s radius is approximately 1.06 times that of Earth based on the transit depth.

Considering the transit’s duration and the star’s properties, the orbital period of HD 137010b is estimated to be around 355 days.

At its distance from the host star, HD 137010b is estimated to receive about 29% of the stellar flux that Earth obtains from the Sun, placing it near the outskirts of the star’s habitable zone.

“If HD 137010b has an atmosphere similar to that of Earth or Mars, it could experience temperatures colder than Antarctica,” noted Dr. Venner.

“However, if the atmosphere thickens, conditions could warm up sufficiently for liquid water to exist, creating a potentially viable environment for life.”

“Current astronomical instruments are unable to fully characterize this newly discovered planet, but it stands out as a primary candidate for future radial velocity tools aimed at detecting Earth-like analogs.”

“Upcoming space missions, like NASA’s Habitable World Observatory, could also provide images of HD 137010b.”

This discovery is detailed in the following article: paper published in Astrophysics Journal Letters.

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Alexander Venner and others. 2026. A cool Earth-sized planet candidate orbiting a K2 magnitude K-dwarf star. APJL 997, L38; doi: 10.3847/2041-8213/adf06f

Source: www.sci.news

Discover How a New Solar Orbiting Spacecraft Connects Magnetic Avalanches to Solar Flares

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Recent high-resolution findings from ESA’s Solar Orbiter mission provide groundbreaking insights into solar flares. These explosive events are triggered by cascading magnetic reconnection processes, releasing immense energy and “raining down” plasma clumps into the Sun’s atmosphere.

Detailed overview of M-class solar flares as observed by ESA’s solar probes. Image credit: ESA / Solar Orbiter / Chitta et al., doi: 10.1051/0004-6361/202557253.

Solar flares are powerful explosions originating from the Sun.

These dramatic events occur when energy stored in entangled magnetic fields is suddenly unleashed through a process known as “magnetic reconnection.”

In mere minutes, intersecting magnetic field lines disconnect and reconnect, leading to a rapid rise in temperature and accelerating millions of degrees of plasma and high-energy particles, potentially resulting in solar flares.

The most intense flares can initiate a cascade of reactions, causing magnetic storms on Earth and potentially disrupting radio communications. Hence, monitoring and understanding these flares is crucial.

However, the mechanisms behind such swift energy release remain largely enigmatic.

An exceptional series of observations from the Solar Orbiter’s four instruments has finally provided clarity. This mission, with its comprehensive approach, offers the most detailed perspective on solar flares to date.

The Solar Orbiter’s Extreme Ultraviolet Imager (EUI) captured high-resolution images of features just hundreds of kilometers across in the Sun’s outer atmosphere (corona), recording changes every two seconds.

Three other instruments—SPICE, STIX, and PHI—examined various depth and temperature regions, from the corona to the Sun’s visible surface, or photosphere.

“We were fortunate to witness this massive flare precursor in such exquisite detail,” said Dr. Pradeep Chitta, an astronomer at the Max Planck Institute for Solar System Research.

“Such detailed and frequent observations of flares are rarely possible due to the limited observation window and the significant data storage required.”

“We were in the right place at the right time to capture these intricate details of the flare.”

Solar Orbiter observations have revealed an intricate view of the central engine during the preflare and shock stages of a solar flare as a magnetic avalanche.

“Even prior to the major flare event, ribbon-like features rapidly traversed the Sun’s atmosphere,” Dr. Chitta noted.

“The flow of these ‘rainy plasma blobs’ indicates increasing energy buildup, intensifying as the flare progresses.”

“This rain of plasma will continue for a while even after the flare diminishes.”

“This marks the first time we’ve observed such a level of spatial and temporal detail in the solar corona.”

“We did not anticipate such high-energy particles emerging from the avalanche process.”

“There is still much to explore regarding this phenomenon, but future missions equipped with high-resolution X-ray imaging will further our understanding.”

“This is one of Solar Orbiter’s most thrilling achievements thus far,” stated Dr. Miho Jamby, ESA’s Solar Orbiter Collaborative Project Scientist.

“The Solar Orbiter’s observations unveil the flare’s central engine and underscore the significant role of an avalanche-like magnetic energy release mechanism.”

There is a compelling prospect of whether this mechanism is universal across all flares and in other flaring stars.

Results can be found in the journal Astronomy and Astrophysics.

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LP Citta et al. 2026. Magnetic avalanches as the central engine driving solar flares. A&A 705, A113; doi: 10.1051/0004-6361/202557253

Source: www.sci.news

Webb Discovers Unique Helium and Carbon-Rich Atmosphere on Exoplanet Orbiting Pulsar

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PSR J2322-2650b, an enigmatic Jupiter-mass exoplanet orbiting the millisecond pulsar PSR J2322-2650, exhibits an unusual atmosphere primarily composed of helium and carbon, presenting a new phenomenon never observed before.

Artist’s concept of PSR J2322-2650b. Image credit: NASA/ESA/CSA/Ralf Crawford, STScI.

“This discovery was completely unexpected,” stated Dr. Peter Gao, an astronomer at the Carnegie Earth and Planetary Institute.

“After analyzing the data, our immediate reaction was, ‘What on Earth is this?’ It contradicted all our expectations.”

“This system is fascinating because we can see the planet lit by its star, yet the star itself is invisible,” explained Dr. Maya Bereznay, a candidate at Stanford University.

“This allows us to capture exceptionally clear spectra, enabling us to study the system in a much more detailed way than we typically do with other exoplanets.”

“This planet orbits a truly unique star—it’s as massive as the sun but as compact as a city,” remarked Dr. Michael Chan from the University of Chicago.

“This represents a new kind of planetary atmosphere never before observed. Instead of the typical molecules like water, methane, and carbon dioxide, we detected carbon molecules, particularly C.3 and C2.”

Molecular carbon is exceedingly rare; at temperatures exceeding 2,000 degrees Celsius, carbon typically bonds with other atoms in the atmosphere.

Out of around 150 planets studied both within and beyond our solar system, none have showcased detectable molecular carbon.

“Did this form as a typical planet? Certainly not, due to its starkly different composition,” Dr. Zhang stated.

“Could it have been created by stripping the outer layers of a star, like what happens in a conventional black widow system? Likely not, as nuclear processes do not yield pure carbon.”

“Envisioning how this drastically carbon-rich composition came to be is quite challenging. All known formation theories seem to be excluded.”

The authors suggest an intriguing phenomenon that might occur in such a unique atmosphere.

“As the companion star cools, the carbon and oxygen mixture within begins to crystallize,” explained Roger Romani, an astronomer at Stanford University and the Kavli Institute for Particle Astrophysics and Cosmology.

“What we observed was pure carbon crystals rising to the surface and blending with the helium.”

“Yet, there must be a mechanism to prevent the oxygen and nitrogen from mixing in. This is where the mystery deepens.”

“However, it’s intriguing not to have all the answers. I’m eager to uncover more about the peculiarities of this atmosphere. Solving these enigmas will be remarkable.”

For more information, refer to the paper published in Astrophysics Journal Letter.

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michael chan et al. 2025. The carbon-rich atmosphere of a windy pulsar planet. APJL 995, L64; doi: 10.3847/2041-8213/ae157c

Source: www.sci.news

Study Reveals Two Moons Orbiting the Trans-Neptunian Object Quaar.

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The recently identified moon has an approximate diameter of 38 kilometers (23.6 miles) and a V magnitude of 28, making it the faintest moon ever found orbiting a trans-Neptunian object.

This image of Quaor and its satellite Waywot was captured by the NASA/ESA Hubble Space Telescope on February 14, 2006. Image credit: NASA / ESA / Hubble / Michael E. Brown.

Discovered on June 4, 2002, Quaor is a trans-Neptunian body approximately 1,100 km (690 miles) in diameter.

Similar to the dwarf planet Pluto, Quaor is located within the Kuiper Belt, a frigid region populated with comet-like objects.

The satellite, also referred to as 2002 LM60, orbits between 45.1 and 45.6 astronomical units (AU) from the Sun, completing an orbit every 284.5 years.

In 2006, astronomers confirmed Quaor’s moon Waywot, measuring 80 km (50 miles) in diameter and orbiting at a radius of 24 around Quaor.

Recently, two rings, designated Q1R and Q2R, were identified surrounding Quaor.

“Stellar occultations over the last decade have indicated the presence of rings around small celestial bodies,” remarked Benjamin Proudfoot, an astronomer at the Florida Space Institute, alongside his colleagues.

“Among these small ring systems, the ring around Quaor is notably enigmatic.”

“The two rings discovered thus far lie well beyond Roche’s limits and exhibit heterogeneity.”

“Quaor’s outer ring, dubbed Q1R, seems to be at least partially confined by mean-motion resonance with Quaor’s moon Waywot, as well as by spin-orbit resonance linked to Quaor’s triaxial structure.”

“The inner ring, Q2R, appears less dense, and its confinement remains more indefinite.”

“Recently, simultaneous dropouts from two telescopes during a stellar occultation indicated the existence of a previously unidentified dense ring around a moon, or Quaor.”

“The length of the dropout suggests a minimum diameter/width of 30 km.”

Artist’s depiction of Quaor and its two rings, with Quaor’s satellite Waywot on the left. Image credit: ESA/Sci.News.

In a recent study, astronomers sought to further characterize the orbit of this new satellite candidate.

They determined that the object is likely on a 3.6-day orbit, close to a 5:3 mean-motion resonance with Quaor’s outermost known ring.

Additionally, they explored the potential for observing satellites through further stellar occultations.

“Quaor will be well-positioned within the Scute nebula for the next 10 years, providing the best opportunity for occultation throughout its 286-year orbit,” the researchers stated.

“Current ground-based and space-based telescopes will struggle to detect the newly discovered moon, given its brightness (9 to 10 magnitude fainter than Quaor) and its angular distance from Quaor.”

“Our analysis of Webb/NIRCam images from the Quaor system did not reveal any convincing evidence of the satellite,” they added.

“Direct imaging with existing equipment would necessitate considerable telescope time to blindly reacquire the satellite’s phase, even if the satellite were detectable.”

“However, future generations of telescopes will likely have the capability to easily observe it.”
The discovery of this new moon suggests that the ring around Quaor may have originally formed from a broad impact disk and may have undergone significant evolution since its creation, according to the researchers.

“Studying the formation and evolution of the lunar disk system will yield valuable insights into the development of trans-Neptunian objects,” they remarked.

“We advocate for advanced tidal mechanics, hydrodynamics, and collisional modeling of the Quaor system.”

The team’s paper has been submitted for publication in Astrophysical Journal Letters.

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Benjamin Proudfoot et al. 2025. Orbital characteristics of a newly discovered small satellite around Quaor. APJL in press. arXiv: 2511.07370

Source: www.sci.news

Astronomers Capture Direct Images of Brown Dwarfs Orbiting Nearby Red Dwarfs

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Astronomers utilized the Subaru Telescope, W.M. Keck Observatory, and ESA’s Gaia mission to capture images of the brown dwarf companion orbiting the M dwarf star LSPM J1446+4633.

NIRC2 image of J1446 taken in August 2023. The white arrow indicates the location of the new companion J1446B. Image provided by: Uyama et al., doi: 10.3847/1538-3881/ae08b6.

LSPM J1446+4633 (J1446) is a nearby mid-M dwarf, situated 17 parsecs (55 light-years) away.

The newly identified brown dwarf orbits its parent star at a distance approximately 4.3 times that of the Earth from the sun, completing an orbit every 20 years.

This object, designated J1446B, has a mass ranging from 20 to 60 times that of Jupiter.

“The success of this discovery was due to the combination of three complementary observational methods: (i) radial velocity (RV) measurements via long-term infrared spectroscopic monitoring by Subaru’s IRD instrument, (ii) high-resolution near-infrared imaging with advanced adaptive optics at the W.M. Keck Observatory, and (iii) precise astronomical acceleration measurements from ESA’s Gaia mission,” stated California State University astronomer Taichi Uyama and his team.

“By integrating these datasets and applying Kepler’s laws, we were able to determine the dynamic mass and orbital parameters of J1446B with unprecedented precision.”

“Radial velocity data by itself cannot differentiate between mass and orbital inclination, but the addition of direct imaging and Gaia data resolves this ambiguity.”

“The Subaru IRD-SSP program provided crucial RV data, while Keck’s cutting-edge adaptive optics allowed for the direct detection of the companion star at very close distances from the host star.”

“Previous studies have shown that astronomical acceleration from Hipparcos and Gaia can be combined with direct imaging to detect and analyze companion objects.”

“However, Hipparcos was unable to measure faint red dwarf stars like J1446.”

“Our study is the first to apply Gaia-only acceleration data to such a system, successfully constraining the orbit and dynamical mass of a brown dwarf companion.”

Near-infrared observations of J1446B indicated a brightness variation of about 30%, hinting at dynamic atmospheric phenomena such as clouds or storms.

“This finding serves as a significant benchmark for testing brown dwarf formation theories and atmospheric models,” the astronomers noted.

“Future spectroscopic studies may enable researchers to map the weather patterns on this intriguing object.”

“This achievement highlights the efficacy of combining ground-based and space-based observatories in discovering hidden worlds beyond our solar system.”

The team’s paper was published in Astronomy Magazine.

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Taichi Uyama et al. 2025. Direct Image Exploration for Companions with Subaru/IRD Strategic Program II. A brown dwarf companion star was discovered around the nearby medium-M dwarf LSPM J1446+4633. A.J. 170, 272; doi: 10.3847/1538-3881/ae08b6

Source: www.sci.news

RadioAstron Reveals Stunning Images of Two Orbiting Supermassive Black Holes

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Astronomers leveraged data from the Radio Astron satellite to generate radio images of two supermassive black holes located at the core of a distant quasar, OJ287. The secondary black hole follows a 12-year orbit around the primary black hole.

The RadioAstron will map two supermassive black holes at the center of galaxy OJ 287, located about 5 billion light-years away in the constellation Cancer. The middle component corresponds to a primary black hole, while the next higher component indicates a secondary black hole, and the highest component represents the knot of its jet. The apparent elongation of the individual components is not real but rather reflects the beam’s shape. Image credit: Valtonen et al., doi: 10.3847/1538-4357/ae057e.

Quasars are exceptionally luminous galactic nuclei whose brightness arises when a supermassive black hole at the galaxy’s center consumes surrounding cosmic gas and dust.

Previously, astronomers have successfully captured images of a black hole at the center of the Milky Way and another in the nearby galaxy known as Messier 87.

“Quasar OJ 287 is so luminous that even amateur astronomers using commercial telescopes can observe it,” remarked Dr. Mauri Valtonen, an astronomer from the University of Turku.

“What sets OJ 287 apart is that it is believed to have two black holes that orbit each other every 12 years, creating a distinct pattern of light fluctuations over the same interval.”

“The earliest observations of OJ 287 date back to the 19th century, captured through old photographs.”

“At that time, the concept of black holes, not to mention quasars, was unimaginable.”

“OJ 287 was inadvertently captured in photographs while astronomers were focused on other celestial objects.”

In 1982, Dr. Valtonen observed that the brightness of the object varied regularly over a 12-year cycle.

He continued his research as a university scholar and proposed that these brightness variations could be due to two black holes orbiting one another.

Numerous astronomers have been closely monitoring quasars to validate this theory and to gain a comprehensive understanding of the orbital motion of the black holes.

The mystery regarding this orbit was finally clarified four years ago by astronomer Lankeswar Dey from the University of Turku.

The only remaining question was whether both black holes could be detected simultaneously.

The solution came from NASA’s TESS satellite, which identified light emission from both black holes.

However, the images captured under normal light lacked the resolution to distinguish the black holes as separate entities, so they were still represented merely as single points.

What was necessary were images with a resolution 100,000 times greater than that attainable by standard radio telescopes.

In this research, Valtonen and his collaborators compared initial theoretical models with radio images.

The two black holes were precisely positioned in the images where they were anticipated to be.

This finding successfully addressed a question that had lingered for four decades: the existence of black hole pairs.

“For the first time, we were able to create images revealing two black holes in orbit around each other,” noted Dr. Valtonen.

“In the image, the black hole is marked by the powerful jets of particles it emits.”

“While the black hole itself is entirely black, it can be identified by the jets of particles and the luminous gas surrounding it.”

Researchers also discovered a completely new type of jet emanating from black holes.

The jet from the secondary black hole of OJ 287 is twisted, resembling the jet from a spinning garden hose.

“This is due to the smaller black hole moving more swiftly around the primary black hole, causing its jet to be deflected according to its current trajectory,” the authors explained.

Their paper was published in the Astrophysical Journal.

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Mauri J. Valtonen et al. 2025. Secondary jet identified in RadioAstron images of OJ 287. APJ 992, 110; doi: 10.3847/1538-4357/ae057e

Source: www.sci.news

Webb Uncovers a New Moon Orbiting Uranus

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Astronomers utilizing the NASA/ESA/CSA James Webb Space Telescope have identified a previously uncharted small moon, provisionally named S/2025 U 1. This discovery, made from a series of images taken on February 2, 2025, brings Uranus’s total number of moons to 29.

This Webb/nircam image illustrates S/2025 U1 along with 13 of the other 28 identified moons. Image credits: NASA/ESA/CSA/STSCI/M. El Moutamid, SWRI/M. Hedman, University of Idaho.

Situated in the outer solar system, Uranus is the seventh planet from the Sun.

This cyan ice giant, often referred to as a “lateral planet” due to its extreme axial tilt, has a thick atmosphere composed of hydrogen, helium, and methane.

The 28 moons of Uranus include five major ones: Titania, Oberon, Ambriel, Ariel, and Miranda, discovered between 1787 and 1948.

Known as “The Literary Moons,” the moons of Uranus are named after characters from the works of Shakespeare and Alexander Pope.

Astronomers estimate that Uranus’s larger moons are approximately equal parts water ice and silicate rock.

“As part of Webb’s Guest Observer program, we discovered a previously unknown satellite of the ice giant,” explained Dr. Maryame El Moutamid, a researcher at the Southwest Research Institute.

“This object is the smallest ever detected and was observed during a set of 10 long exposures captured by Webb’s near-infrared camera (NIRCAM).”

https://www.youtube.com/watch?v=pa8joehgtg

The moon, provisionally designated S/2025 U1, resides at the end of Uranus’s inner ring.

Estimated to have a diameter of only 10 km (6 miles), its reflectance (albedo) is presumed to be similar to that of other small Uranian satellites.

It is located approximately 56,250 km (35,000 miles) away from the Earth’s equatorial plane, positioned between the orbits of Ophelia and Bianca.

Ophelia has a diameter of about 43 km (13 miles), while Bianca is elongated, measuring 64 x 46 km (40 x 29 miles).

“While it’s a small moon, its discovery is significant. This is something that even NASA’s Voyager 2 spacecraft missed during its flybys nearly 40 years ago,” Dr. El Moutamid remarked.

S/2025 U1 becomes the 14th member of a complex system of small moons, circling inward among the larger moons, including Miranda, Ariel, Umbriel, Titania, and Oberon.

“Unlike other planets, Uranus possesses a remarkable number of small inner moons. The intricate interactions with its ring system indicate a chaotic history that merges the ring and lunar systems,” Dr. El Moutamid noted.

“Furthermore, this new moon’s small size and unexpected nature may lead to the discovery of even more complexities.”

Source: www.sci.news

Can Exoplanets Orbiting TRAPPIST-1 and Other Red Dwarfs Support Life?

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A protective atmosphere, a welcoming sun, and abundant liquid water make Earth a remarkable place. Leveraging the extraordinary capabilities of the NASA/ESA/CSA James Webb Space Telescope, astronomers are on a mission to uncover just how unique and extraordinary our planet truly is. Is it possible for a temperate environment to exist elsewhere, perhaps around a different type of star? The TRAPPIST-1 system offers an intriguing opportunity to explore this question, as it contains seven Earth-sized planets orbiting red dwarf stars—the most common type in the Milky Way.

The artist’s concept depicts TRAPPIST-1d passing in front of a turbulent star, showing the other planets in the background. Image credits: NASA/ESA/CSA/Joseph Olmsted, STSCI.

TRAPPIST-1 is a super cool dwarf star situated 38.8 light-years away in the constellation Aquarius.

These stars are slightly larger than Jupiter, comprising only 8% of our Sun’s mass. They rotate quickly and emit UV energy flares.

TRAPPIST-1 is home to seven transiting planets designated TRAPPIST-1b, c, d, e, f, g, and h.

All these planets are similar in size to Earth and Venus, or marginally smaller, with very brief orbital periods of 1.51, 2.42, 4.04, 6.06, 9.21, 12.35, and 20 days, respectively.

They may all be tidally locked, meaning the same side always faces their star, akin to how the same side of the moon is always turned towards Earth. This results in a permanently night side and a permanently day side for each TRAPPIST-1 planet.

“Ultimately, we aim to discover whether similar environments to those we enjoy on Earth exist elsewhere, and under what conditions they might thrive,” stated Dr. Caroline Piaulett Graeb, an astronomer at the University of Chicago and the Trottia Institute for Planetary Research.

“At this stage, we can exclude TRAPPIST-1d as a potential twin or cousin of Earth, even as Webb enables us to investigate Earth-sized planets for the first time.”

Dr. Piaulet-Ghorayeb and her team utilized Webb’s NIRSpec (near-infrared spectroscopy) instrument to capture the transmission spectra of the TRAPPIST-1d planet.

They found no common molecules typically present in Earth’s atmosphere, such as water, methane, or carbon dioxide.

However, they have outlined several possibilities for the exoplanet that warrant further investigation.

“There are multiple reasons we might not detect an atmosphere around TRAPPIST-1d,” Dr. Piaulet-Ghorayeb mentioned.

“It may have a very thin atmosphere, similar to Mars, which is challenging to identify.”

“Alternatively, thick, high-altitude clouds may obscure certain atmospheric signatures.”

“Or it could be a barren rock with no atmosphere whatsoever.”

In any case, TRAPPIST-1d faces challenges as a planet orbiting a red dwarf star.

TRAPPIST-1, the host star of the system, is known for its volatility and often emits high-energy radiation flares that can strip away the atmosphere of nearby small planets.

Nevertheless, scientists remain eager to search for atmospheric signs on the TRAPPIST-1 planets, as red dwarfs are the most prevalent stars in our galaxy.

If these planets can retain an atmosphere here, it suggests they could potentially do so anywhere, even under the harsh conditions of stellar radiation.

“Webb’s sensitive infrared instruments allow us to probe into the atmospheres of these small, cold planets for the first time,” said Dr. Bjorn Beneke, an astronomer at the Institute for Planetary Research at Montreal University.

“We are using Webb to identify atmospheres on Earth-sized planets and define the thresholds between those that can and cannot sustain an atmosphere.”

Results will be published in Astrophysical Journal.

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Caroline Piaulett Graeb et al. 2025. Restrictive conditions on the potential secondary atmosphere of the temperate rocky exoplanet TRAPPIST-1d. APJ 989, 181; doi:10.3847/1538-4357/ADF207

Source: www.sci.news

Astronomers Discover a Novel Type of Plasma Wave Orbiting Jupiter

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Unusual Behaviour of Plasma at Jupiter’s Poles

NASA/JPL-CALTECH/SWRI/MS SS; Oleksuik © CC NC SA

Jupiter’s surrounding space is among the most unique in our solar system, and the plasma present is equally remarkable, exhibiting unprecedented wave patterns.

Robert Lysak, from the University of Minnesota, explores Aurora phenomena. These captivating displays of green and blue light on Earth are accompanied by nearly undetectable ultraviolet rays near Jupiter’s poles.

To comprehend the auroras on this distant planet, it’s vital to grasp the intricacies of the plasma that generates these lights—a mix of charged particles and atomic components that envelopes the planet. Insights gathered from NASA’s Juno spacecraft have led Lysak and his team to identify that Jupiter’s Auroral Plasma resonates with a novel type of wave.

This newly identified wave is a combination of two well-characterized types of plasma waves: the Alfven wave, which arises from the motion of charged particles, and the Langmuir wave, which corresponds to electron movement. Lysak points out that since electrons are much lighter than charged particles, these two kinds of waves typically oscillate at vastly different frequencies.

However, the environment near Jupiter’s poles possesses conditions ideal for both waves to oscillate together. This is enabled by the low density of the plasma in that region and the strong magnetic field exerted by the planet.

“The plasma characteristics observed are truly unique when compared to those in other parts of our solar system,” states John Leif Jorgensen at the Institute of Technology Denmark. With Juno’s data uncovering new wave patterns, he believes we can learn more about the magnetic attributes of distant exoplanets by looking for similar signals.

Juno is currently in orbit around Jupiter, with Lysak noting that if its mission is extended, it could provide unparalleled insights into the giant planet and its complexities. This mission, however, is one among several that may face cuts due to proposed NASA budget reductions.

“Discontinuing missions while they are yielding valuable data would be a significant setback for our field,” concludes Lysak.

Topics:

Source: www.newscientist.com

Giant Exoplanet Discovered Orbiting Low-Mass Star TOI-6894

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The identification of TO-6894B, an exoplanet roughly 86% the size of Jupiter orbiting the low-mass Redd star (0.2 solar masses), underscores the importance of enhancing our comprehension of the formation mechanisms of giant planets and their protoplanetary disc environments.

Artist’s illustration of TOI-6894B behind its host star. Image credit: Markgarlic/Warwick University.

The TOI-6894 system is located approximately 73 parsecs (238 light years) away in the Leo constellation.

This planet was discovered through a comprehensive analysis of data from NASA’s Transiting Exoplanet Survey Satellite (TESS), aimed at locating giant planets around low-mass stars.

“I was thrilled by this discovery. My initial focus was on observing a low-mass red star with TESS, in search of a giant planet,” remarked Dr. Edward Bryant, an astronomer from the University of London.

“Then, utilizing observations from ESO’s Very Large Telescope (VLT), one of the most substantial telescopes globally, I identified TO-6894B, a giant planet orbiting the smallest known star with such a companion planet.”

“I never anticipated that a planet like TOI-6894B could exist around such a low-mass star.”

“This finding will serve as a foundational element in our understanding of the boundary conditions for giant planet formation.”

TOI-6894B is a low-density gas giant, with a radius slightly exceeding that of Saturn, which has only 50% of its mass.

The parent star is the lowest mass star yet found to host a massive planet, being just 60% of the mass of the next smallest star observed with such a planet.

“Most stars in our galaxy are actually small, and it was previously believed that they couldn’t support a gas giant,” stated Dr. Daniel Baylis, an astronomer at Warwick University.

“Therefore, the fact that this star has a giant planet significantly impacts our estimates of the total number of giant planets likely to exist in the galaxy.”

“This is a fascinating discovery. We still don’t completely understand why relatively few stars can form such large planets,” commented Dr. Vincent Van Eilen, an astronomer at the University of London.

“This drives one of our objectives to search for more exoplanets.”

“By exploring different planetary systems compared to our own solar system, we can evaluate our models and gain insights into how our solar system was formed.”

The prevailing theory of planetary formation is known as core accretion theory.

According to this theory, the cores of planets are initially formed by accreting material, and as the core grows, it attracts gases that eventually create its atmosphere.

Eventually, the core becomes sufficiently large to initiate the runaway gas accretion process, leading to the formation of a gas giant.

However, forming gas giants around low-mass stars presents challenges, as the gas and dust necessary for planetary formation in their protoplanetary discs is limited, hindering the formation of a sufficiently large core to kickstart this runaway process.

The existence of TOI-6894B indicates that this model may be insufficient and that alternative theories need to be considered.

“Considering TO-6894B’s mass, it might have been formed through an intermediate core-fault mechanism, whereby the protoplanet forms and accumulates gas steadily without orbiting, making it large enough to undergo runaway gas accretion,” Dr. Edward explained.

“Alternatively, it might have formed due to an unstable gravitational disk.”

“In certain cases, the disk surrounding the star can become unstable due to the gravitational forces it exerts on itself.”

“These disks may fragment as gas and dust collapse, leading to planet formation.”

However, the research team found that neither theory fully accounted for the formation of TOI-6894B based on the data available.

“Based on the stellar irradiation affecting TOI-6894B, we anticipate that its atmosphere is primarily influenced by methane chemistry, which is quite rare to identify.”

“The temperatures are low enough that atmospheric observations may even reveal the presence of ammonia.”

TOI-6894B might serve as a benchmark for methane-dominated atmospheric studies and an ideal laboratory for investigating planetary atmospheres containing carbon, nitrogen, and oxygen beyond our solar system.

Survey results will be featured in the journal Nature Astronomy.

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Bryant et al. A giant exoplanet in orbit around a 0.2 solar mass star. Nature Astronomy, Published online on June 4th, 2025. doi:10.1038/s41550-025-02552-4

Source: www.sci.news

Astronomers Identify Potential Dwarf Planets Orbiting Every 25,000 Years

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The recently identified Transneptunian object, which was named in 2017, stands out as one of the most prominent objects in our solar system, measuring approximately 700 km in diameter, thus qualifying as a dwarf planet.

All cut-out images of 19 detections for 2017 2017. Image credits: Chen et al, arxiv: 2505.15806.

Transneptunian Objects (TNOs) are small celestial bodies that orbit the Sun at distances greater than that of Neptune.

In the 30 years following the discovery of the first TNO outside Pluto, numerous research initiatives have been launched to explore the expansive regions of the outer solar system, resulting in the identification of over 5,000 TNOs to date.

The newly discovered TNO is significant for two main reasons: its unique trajectory and substantial size.

“The object’s aphelion—the furthest point in its orbit from the Sun—is over 1,600 times the distance of Earth’s orbit,” states Dr. Sihao Chen, an astronomer at the Institute of Advanced Research and Boundary Research.

“Conversely, its perihelion—the closest point in its orbit to the Sun—is 44.5 times that of Earth’s orbit, akin to Pluto’s orbit.”

“This extreme trajectory takes around 25,000 years to complete, suggesting a complex gravitational history,” he adds.

“We likely experienced a close encounter with a massive planet, compelling us into this wide orbit,” comments Princeton University astronomer Dr. Elitas Yang.

“There may have been multiple phases in this transition.”

“The object might have initially been ejected into the Oort Cloud, the outermost region of the solar system, which is home to numerous comets.”

“Many extreme TNOs appear to follow similar trajectories, but 2017 OF201 stands out as an anomaly,” remarks Dr. Jiaxuan Li, also from Princeton University.

“This clustering is interpreted as indirect evidence suggesting the presence of another celestial body, often referred to as Planet X or Planet Nine, which could be influencing these objects through gravitational forces.”

“The existence of 2017 OF201 as an outlier in this clustering could potentially challenge this hypothesis.”

Astronomers estimate the diameter of 2017 OF201 to be 700 km, making it the second-largest object on such an extensive orbit.

“2017 OF201 can only be detected about 1% of the time when it is relatively close to us,” Dr. Chen notes.

“The presence of this solitary object implies that there may be around 100 other similar objects with comparable trajectories and sizes.”

Researchers discovered 2017 OF201 as part of an ongoing initiative to identify TNOs and potential new planets in the outer solar system.

The detection involved identifying bright spots in astronomical image databases from the Victor M. Blanco Telescope and the Canada France Hawaii Telescope (CFHT), as well as attempting to trace groups of possible spots that indicate TNO movement across the sky.

Scientists identified 2017 OF201 in 19 different exposures collected over a span of seven years.

“Although advancements in telescopic technology have allowed us to explore distant realms of the universe, much remains to be uncovered within our own solar system,” concludes Dr. Chen.

The team’s paper has been published online at arxiv.org.

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Sihao Cheng et al. 2025. Discovery of new planet candidates in extremely wide orbits: 2017 OF201. arxiv: 2505.15806

Source: www.sci.news

Discovery of a Compact Binary System: A Neutron Star Orbiting Within Another Star

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This binary system comprises a PSR J1928+1815 along with a rapidly spinning millisecond pulsar known as the Helium Star Companion.

The AI impression of the compact binary system. Image credit: Gemini AI.

The millisecond pulsar consists of rapidly rotating neutron stars that emit radio waves.

These stars attain remarkable rotational velocities by harvesting material from surrounding stellar groups.

The development of such exotic binary systems remains partially understood, as it encompasses a range of complex processes.

The theory suggests that binary systems may undergo a common envelope phase, where a star orbits within the outer layer of its companion.

If the companion in this evolutionary phase is a neutron star, the theory indicates that the outer layer will be swiftly ejected, resulting in a binary system of recycled pulsars and stripped helium stars.

In the recent study, Dr. Zonglin Yang, a national astronomer at the Chinese Academy of Sciences, along with colleagues, examined the millisecond pulsar PSR J1928+1815.

Utilizing data from a high-speed 500-meter aperture spherical radio telescope, they discovered that the pulsar has a spin period of 10.55 ms and resides in a close binary system with companion helium stars, completing an orbit every 3.6 hours.

They employed a stellar model to demonstrate that this system originated following an unstable mass transfer from companion stars to neutron stars, leading to the formation of a common envelope around both stellar objects.

The neutron star approached the core of the other star, ejected the outer envelope, and released energy, resulting in a tightly bound binary system.

“The companion star has a mass between 1.0 and 1.6 solar masses, obscuring the pulsar approximately 17% of its orbit and is undetectable at other wavelengths, suggesting it is likely a stripped helium star,” the authors noted.

“We interpret this system as having recently undergone a common envelope phase to create compact binaries.”

“Such systems are thought to be rare, yet we anticipate the existence of others,” they added.

“We estimate that there could be between 16 and 84 undiscovered examples within the Milky Way.”

The findings are documented in a paper published in the journal Science.

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Zl Yang et al. 2025. A pulsar helium star compact binary system formed by common envelope evolution. Science 388 (6749): 859-863; doi: 10.1126/science.ado0769

Source: www.sci.news

Webb successfully captures images of several massive exoplanets orbiting two youthful stars

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Astronomers using Near-infrared camera (NIRCAM) NASA/ESA/CSA James Webb Space Telescope equipped and captured corona graphic images of the HR 8799 and 51 Eridani Planetary Systems. These observations revealed HR 8799 and four known gas giants around 51 Eridani. They also revealed that all HR 8799 planets are carbon dioxide-rich.

This Webb/Nircam image shows the multiplanet system HR 8799. Image credits: NASA/ESA/CSA/STSCI/W. BALMER, JHU/L. PUEYO, STSCI/M. PERRIN, STSCI.

HR 8799 is a star from 30 million years ago, about 129 light years away from the Pegasus constellation.

Hosts large chip disks and four supergipers: HR 8799b, c, d, and e.

Unlike most exoplanet discoveries inferred from data analysis, these planets are seen directly via ground telescopes.

“We have shown that the atmosphere of these planets has quite a lot of heavy elements, such as carbon, oxygen and iron.

“Given what we know about the stars, it's likely that it indicates that they were formed through Core landing this is an exciting conclusion for the planet we can see firsthand. ”

The planets within HR 8799 are still hot from the formation of the turbulent, ejecting a large amount of infrared rays that provide valuable data about how scientists formed.

Giant planets can take shape in two ways. Like giants in the solar system, by slowly building heavy elements that attract gas, or the particles of gas rapidly merge into giant objects from a cooling disk of a young star made of the same kind of material as the stars.

The first process is called core accretion and the second is called disk instability.

Knowing which formation models are more common can provide clues to scientists distinguish the types of planets they have found in other systems.

“Our hope in this type of study is to understand our own solar system, life and ourselves, in comparison to other exoplanet systems.

“We want to take photos of other solar systems and see how they look similar or different from us.”

“From there we can feel how strange or normal our solar system is.”

This Webb/Nircam image shows the 51 Eridani system. Image credits: NASA/ESA/CSA/STSCI/W. BALMER, JHU/L. PUEYO, STSCI/M. PERRIN, STSCI.

51 Eridanus is located approximately 97 light years from Earth in the constellation of Eridanus.

51 If called ERI, C ERIDANI, or HD 29391, the star is only 20 million years old and by astronomy standards it is merely a toddler.

Host one giant planet, 51 Eridani B. It orbits the star at a distance of approximately 13 AU (astronomical units), equivalent to that of Saturn and Uranus in the solar system.

Images of HR 8799 and 51 rib ticks were made possible by Webb's Nircam Coronagraph.

This technique allowed astronomers to look for infrared rays emitted by planets at wavelengths absorbed by a particular gas.

They discovered that the four HR 8799 planets contain more heavy elements than previously thought.

“There is other evidence suggesting these four HR 8799 planets formed using this bottom-up approach,” says Dr. Laurent Puueyo, an astronomer at the Institute of Space Telescope Science.

“How common is this on planets we don't know yet?

“We knew that Webb could measure the colour of outer planets in a directly imaged system,” added Dr. Remi Somer of the Institute of Space Telescope Science.

“We waited for 10 years to ensure that the finely tuned operations of the telescope had access to the inner planet.”

“We now have results and we can do some interesting science.”

Survey results It was published in Astronomy Journal.

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William O. Balmer et al. 2025. JWST-TST High Contrast: Living on the Wedge, or Nircam Bar Coronagraph reveals CO2 HR 8799 and 51 ERI extracts atmosphere. AJ 169, 209; doi:10.3847/1538-3881/ADB1C6

Source: www.sci.news

New Evidence of Four Subexternal Planets Discovered Orbiting Bernard’s Star

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For a century, astronomers have been studying Bernard's stars in the hopes of finding planets around them. First discovered by Ee Barnard at the Yerkes Observatory in 1916, it is the closest single star system to Earth. I'm using an astronomer now Maroon-X Instruments At the Gemini Northeres Scope, half of the NSF's International Gemini Observatory, there is solid evidence of three exoplanets around Bernard's star, two of which were previously classified as candidates. We also combined data from Maroon-X with data from Espresso instrument ESO's very large telescope confirms the existence of a fourth planet and raises it from candidate to candidate genuine exoplanet.

Illustration of an exoplanet artist orbiting Bernard's star. Image credits: International Gemini Observatory / Noirlab / NSF / Aura / P. Marenfeld.

Bernard's star is an M3.5 type star in the constellation of Ophetus.

Alpha Centauri's triple steller system is the closest star to the Sun, almost six light years away.

Also known as the Gliese 699 or GJ 699, Bernard's star is thought to be 10 billion years old due to its slow spin and low levels of activity.

According to a new study, stars host at least four planets, each with only about 20-30% of the Earth's mass.

They are very close to their home star, so in a few days they zip around the entire star.

It probably means they are too hot so uninhabitable, but this discovery is a new benchmark for discovering small planets around nearby stars.

“It's a really exciting discovery. The Bernard star is our universe's neighbor, but even so, we know little about it,” said doctoral degree Ritvik Basant. A student at the University of Chicago.

“The accuracy of these new instruments from previous generations signal a breakthrough.”

Stars are much brighter than planets, so it's easy to find the effects that planets have on them – such as watching the wind by seeing how the flag moves.

The Maroon-X instrument looks for one such effect. The gravity of each planet is pulled slightly towards the position of the star. In other words, the stars seem to wobble back and forth.

Maroon-X can measure the color of light very accurately, pick up these small shifts, and even bully the number of planets that have to circumvent the stars to have this effect.

Basant and colleagues rigorously coordinated and analyzed data taken on 112 different nights over three years.

They found solid evidence of three planets around Bernard's star.

When the team combined the findings with data from espresso instruments, they saw good evidence of the fourth planet.

“These planets are probably rocky planets, not gas planets like Jupiter,” the astronomer said.

“It would be hard to secure it secured. The angle seen from Earth means that they cannot see them crossing in front of the stars.

“But by gathering information about similar planets around other stars, we can make better guesses about their makeup.”

Team's Survey results It was released today Astrophysics Journal Letter.

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Ritvik Basant et al. 2025. Four sub-Earth planets orbiting Bernard's star from Maroon X and Espresso. apjl 982, L1; doi: 10.3847/2041-8213/ADB8D5

Source: www.sci.news

A ring filled with nine stars found orbiting a massive galaxy by astronomers

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The astronomers have identified nine rings using NASA/ESA Hubble Space Telescope and WM KECK Observatory’s KECK COSMIC Web Imager (KCWI) data.

Pasha et al。 Nine rings around the Leda 1313424, a ring galaxy, about 567 million lights, have been detected around the constellation of Pisces. They also confirmed that the galaxy had pigeons and created these rings through the Reda 1313424. Image Credit: NASA / ESA / HUBBLE / IMAD PASHA & Pieter Van Dokkum, Yale University.

LEDA 1313424 A ring galaxy found in the image of Legacy Survey Dr9 in 2019.

The galaxy called Bulls Eye’s nickname has an reddish transition of Z = 0.0394 corresponding to the distance of 567 million light years.

The diameter of LEDA 1313424 is 250,000 light years. This is almost 2.5 times that of the Milky Way galaxy.

“This was an accidental discovery,” said Imado Pasha, a student in the Yale University doctoral course.

“I was looking at a ground -based imaging survey, but when I saw a galaxy with some transparent rings, I was immediately drawn to it. I had to stop to investigate it. did.”

Approximately 50 million years ago, a small blue dwarf galaxy moved like a dart that passed the core of LEDA 1313424.

With this collision, 10 rings were created around LEDA 1313424. This has detected nine unprecedented rings.

A thin gas trail links the pair, but is currently 130,000 light years away.

“We are catching Bulls Eye at a very special moment,” said Professor Peter Van Dockm of Yale University.

“When there are many rings in such a galaxy, there is a very narrow window after the impact.”

Researchers used Hubble’s clear vision to identify the eight rings of LEDA 1313424 and check another ring using KECK.

They also discovered a brilliant connection between Ring Galaxy and many years. The galaxy ring seems to have moved almost exactly as expected as the model predicted.

“The theory was developed on the day I saw a lot of rings,” said Professor Van Dokum.

“I am very pleased to confirm the predictions for these years in the Bulls Eye Galaxy.”

From the top, it is clear that the Galaxy ring is not evenly spaced like a Dart board. The image of Hubble shows the galaxy from a slight angle.

“If you look down on the galaxy directly, the ring looks circular, the ring will be bundled in the center, and will gradually be far away and gradually break away,” Pasha explained.

a paper Regarding this discovery, it was released today Astronomical physics journal letter。

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Imad Pasha et al。 2025. Bullsia: HST, KECK/KCWI, and the characteristics of the giant 9 -ring dragon fly. APJL 980, L3; DOI: 10.3847/2041-8213/AD9F5C

Source: www.sci.news

Astronomers Confirm Existence of Three Exoplanets Orbiting Nearby Solar-Type Stars.

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G-Dwarf is one of these outside planets, HD 20794D, which is likely to be a rocky planet where the parent’s star can live. HD 20794。

This image shows a resident zone around HD 20794 (green) and three planets in the system. Image credit: Gabrielpérezdíaz / smm / IAC.

“HD 20794 is not a normal star in HD 20794D,” said UNIGE ASTRONOMER XAVIER DUMUSQUE.

“Due to its lightness and proximity, it becomes an ideal candidate for the future telescope, and its mission is to directly observe the atmosphere of the outside planet.”

The HD 20794 is a bright G6V star in 6.04 % (19.7 light year) on the constellation of Ellidanus.

Stars, also known as LHS 19 or ERI, host at least three large -scale outside planets: HD 20794B, C, and D.

They have a track period of 18.3, 89.7, and 647.6 days, along with 2.2, 3, and 5.8 global quality.

“The interest of Super Earth Planet The HD 20794D is located in a zone where the stars can live and the place where liquid water can exist.

“Instead of tracing a relatively circular orbit like the Earth or Mars, the HD 20794D trains an elliptical trajectory with a large change in the distance to the star during the revolution.”

“Therefore, the planet vibrates between the inner ends of the star -free zone (0.75 au) and the track (2 au).”

“If there is water in the HD 20794D, it will promote the appearance of life from ice state to liquid state during the Earth revolution around the stars.”

Astronomer monitored the HD 20794 system with the ESO’s very large telescope (VLT) in the paranal of Chile, the Echelle branch device of the rocky planet and the stable spectrum observation (espresso) device.

They participated in espresso data along with the data of the high -precision radial speed planetary searcher (HARPS) device installed in the 3.6 -meter telescope of Chile, including archive data and new measurements from recent archives and new measurements.

“The HD 20794 system is a high -priority target for future air characteristics evaluation with direct imaging facilities,” said researchers.

Their paper Published in the journal Astronomy and astronomical physics。

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N. Nari et al。 2025. Review of nearby star HD 20794 multi -planet system A & A 693, A297; DOI: 10.1051/0004-6361/202451769

Source: www.sci.news

New Evidence of Volcanic Exomoon Found Orbiting WASP-49Ab by Astronomers

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Using the ESPRESSO instrument on ESO’s Very Large Telescope and the HARPS instrument on ESO’s La Silla 3.6-meter telescope, astronomers discovered the hot Saturn-sized gas giant exoplanet WASP-49Ab, which is close to but slightly synchronized. Detected a sodium cloud with a shifted position.

This artist’s concept depicts a volcanic exomoon that could exist between WASP-49Ab (left) and its parent star. Image credit: NASA/JPL/California Institute of Technology.

WASP-49A is a faint sun-like star discovered in 2006 by the Wide Angle Planet Survey (WASP).

The star, also known as 2MASS 06042146-1657550, is located in the constellation Lepus, about 635 light-years from Earth.

The transiting Saturn-mass companion star, WASP-49Ab (also known as WASP-49b), was discovered in 2012 in a 2.8-day orbit.

“Both WASP-49Ab and its star are composed mostly of hydrogen and helium, with trace amounts of sodium,” said Caltech astronomer Apurva Oza.

“Neither of these contain enough sodium to cause clouds, and the clouds appear to be coming from sources that are producing about 100,000 kg of sodium per second.”

“Even if stars and planets were able to produce that much sodium, it is unclear what mechanism would allow them to emit sodium into space.”

Oza and his colleagues found some evidence to suggest that the cloud was produced by another object orbiting WASP-49Ab, but additional research is needed to confirm the cloud’s behavior. .

For example, their two observations showed that when the cloud was not next to the planet, it suddenly increased in size, as if it had been refueled.

They also observed that the clouds were moving faster than the planets. This seems impossible unless the clouds are generated by another object that moves independently and faster than the planet.

“We think this is very important evidence,” Dr. Oza said.

“The cloud is moving in the opposite direction that physics tells it should go if it were part of the planet’s atmosphere.”

Astronomers have demonstrated that this cloud is located above the planet’s atmosphere, similar to the gas clouds that Io produces around Jupiter.

They also used a computer model to explain the exomoon scenario and compared it to data.

WASP-49Ab orbits the star every 2.8 days with clock-like regularity, but the cloud appears and disappears behind the star and planet at seemingly irregular intervals.

The researchers used a model to show that exomoons with eight-hour orbits around the planet sometimes appeared to move in front of the planet or did not appear to be associated with certain clouds. It was shown that it is possible to explain the movement and activity of clouds, such as how they move. region of the planet.

“The evidence that something other than a planet or star is producing this cloud is very convincing,” said Dr. Rosalie Lopez, a planetary geologist at NASA’s Jet Propulsion Laboratory.

“The detection of an exomoon is highly unusual, but thanks to Io we know that volcanic exomoons are possible.”

of findings Published in Astrophysics Journal Letter.

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Apurva V. Oza others. 2024. Redshifted sodium transient near an exoplanet transit. APJL 973, L53; doi: 10.3847/2041-8213/ad6b29

Source: www.sci.news

Newly Found Planet Orbiting Barnard’s Star Only 6 Light Years from Earth

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Artist’s impression of Barnard’s b, a planet orbiting around Barnard’s star

ESO/M.Kornmesser

Barnard’s star, one of the Sun’s closest neighbors, appears to have at least one planet orbiting around it, and possibly three more that require further confirmation.

Astronomers have been searching for planets around Barnard’s star, 5.96 light-years away, since the 1960s. Barnard’s star is the next closest star to us after the three stars in the Alpha Centauri star system.

In 2018, researchers claimed to have discovered a planet at least three times the size of Earth called Barnard Star B, but subsequent analysis revealed that the apparent planet’s signal was actually a larger-than-expected star. Turns out it was caused by activity. .

now, Jonay González Hernández Researchers at the Canary Islands Institute of Astrophysics have announced the discovery of a new Barnard star b, which has about 40 percent the mass of Earth.

The planet is much closer to its star than any other planet in our solar system, completing an orbit in just over three Earth days. This also means that its surface temperature is around 125°C (257°F), too hot for liquid water or life to exist.

Using an instrument called Espresso on the European Southern Observatory’s Very Large Telescope in Chile, González Hernández and his team observed tiny wobbles in Barnard’s star’s position caused by the orbiting planet’s gravity. I discovered this star.

They also found evidence of three more planets orbiting the star. However, the signal wasn’t strong enough to be certain, so more observations will be needed to confirm that.

“These detections are very tricky and always difficult because there is stellar activity, the magnetic field of the star that rotates with the star,” he says. Rodrigo Fernando Diaz at the National University of San Martin, Argentina. González Hernández and his team have thoroughly checked whether the observations are from a planet, but there could always be “unknown unknowns,” Fernando Díaz said. says. To really confirm this, he says, data from other telescopes is needed, which could take years of observations.

topic:

Source: www.newscientist.com

Webb captures direct image of a temperate superjupiter orbiting Epsilon Indi A

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Astronomers Webb’s MIRI (Mid-Infrared Instrument) The image was taken of Epsilon Indi Ab, a gas giant several times the mass of Jupiter, located about 12 light years from Earth.

This image of Epsilon Indi Ab was taken with a coronagraph on Webb’s MIRI instrument. Image courtesy NASA / ESA / CSA / Webb / STScI / E. Matthews, Max Planck Institute for Astronomy.

Of the 25 planets that have been directly imaged to date, all are less than 500 million years old, and all but six are less than 100 million years old.

The newly imaged planet orbits Epsilon Indi A (HD 209100, HIP 108870), a K5V type star that is roughly the age of the Sun (3.7 to 5.7 billion years).

“Previous observations of this system have been more indirect measurements of the star, which gave us advance knowledge that there is likely to be a giant planet in the system tugging at the star,” said Dr Caroline Morley, an astronomer at the University of Texas at Austin.

“That’s why our team chose this system as our first observational system at Webb.”

“This discovery is fascinating because the planet is very similar to Jupiter – it’s a little warmer and more massive, but it’s more similar to Jupiter than any other planet imaged so far,” said Dr Elizabeth Matthews, astronomer at the Max Planck Institute for Astronomy.

“The cold planet is very dark and most of its radiation is in the mid-infrared. Webb is ideal for mid-infrared imaging, but it’s very difficult to do from the ground.”

“We also needed good spatial resolution to distinguish planets from stars in the images, and the large Webb mirror helps a lot in this regard.”

Epsilon Indi Ab is one of the coolest exoplanets ever directly detected, with an estimated temperature of 2 degrees Celsius (35 degrees Fahrenheit). This makes it the coolest planet ever imaged outside the solar system, and cooler than all but one free-floating brown dwarf.

The planet is only about 100 degrees Celsius (180 degrees Fahrenheit) warmer than the gas giants in our solar system.

This provides astronomers with a rare opportunity to study the atmospheric composition of a true solar system analogue.

“Astronomers have imagined there could be planets in this system for decades, and fictional planets orbiting Epsilon Indi have been the setting for Star Trek episodes, novels and video games such as Halo,” Dr Morley said.

“It’s exciting to actually see the planet out there and start measuring its properties.”

Epsilon Indi Ab is the 12th closest exoplanet currently known to Earth and the closest planet with a mass greater than Jupiter.

Astronomers chose to study Epsilon Indi A because the system suggested the possibility of planets, using a technique called radial velocity, which measures the back and forth wobble of the host star along the line of sight.

“We expected there to be a planet in this system because the radial velocity suggested its presence, but the planet we found was different to what we expected,” Dr Matthews said.

“It’s about twice as massive, it’s a little farther from its star, and its orbit is different from what we would expect. We don’t yet know what causes this discrepancy.”

“The planet’s atmosphere also seems to differ slightly from what the models predict.”

“So far, only a few atmospheric photometry measurements have been made, making it difficult to draw any conclusions, but the planet is fainter than expected at shorter wavelengths.”

“This could mean that there is a lot of methane, carbon monoxide and carbon dioxide in the planet’s atmosphere, absorbing shorter wavelengths of light. It could also suggest a very cloudy atmosphere.”

a paper The findings were published in the journal. Nature.

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E.C. Matthews othersA temperate superjupiter photographed in mid-infrared by JWST. NaturePublished online July 24, 2024, doi: 10.1038/s41586-024-07837-8

This article has been edited based on the original NASA release.

Source: www.sci.news

Is it possible for liquid water to exist on planets orbiting dwarf stars?

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Denis Villeneuve's sci-fi masterpiece Dune: Part 2 The film hits theaters in the US in spring 2024. The movie follows the power struggles of the noble families of the desert planet Arrakis. But what if humanity had become an empire that spanned thousands of worlds in the distant future, as depicted in the film? Sand Dunes How common are desert planets or planets with no water at all in movies and novels?

In the search for these planets, a good place to start is with the most common stars: astronomers have observed what are called small, faint, cool, reddish stars. Red dwarf They make up most of the stars in the galaxy. Astronomers who study planets around stars other than the Sun estimate that every star has at least one planet. About half of the planets around red dwarfs are small, rocky planets with compositions similar to Earth. On the ground planet. Therefore, the most common type of terrestrial planet is thought to be around a red dwarf star.

For decades, astronomers have thought that red dwarfs are too cold for liquid water to exist on their surfaces. To reach the temperature range needed to support liquid water, planets around cooler stars need to orbit closer to their host stars than planets around hotter ones. But unlike stars like the Sun, which have a constant brightness, red dwarfs are born hotter and brighter than their final state for most of their lives.

The terrestrial planets formed with 15 to 70 times more water than Earth, most of it coming from drifting icy comets. But the heat of the young red dwarf star causes the water on these planets to evaporate, turning from liquid to gas in their atmospheres. In the planet's atmosphere, the intense starlight breaks down the water vapor into oxygen and hydrogen. Photolysis. The heavier oxygen stays on the planet while the lighter hydrogen drifts away, and astronomers estimate that as a result, planets around red dwarf stars lose tens of times as much water as Earth's oceans over their first billion years.

A team of Japanese scientists led by Hiroshi Kawamura challenged the paradigm that planets around red dwarfs should lose all their water in this way. They proposed that two factors could significantly reduce the initial water loss of planets orbiting dwarf stars. First, water is decomposed by the intense light in the planet's atmosphere, but some water is produced in the atmosphere when reactive free hydrogen mixes with hydrogen superoxide. Second, the decomposition of water in the atmosphere produces oxygen gas, which protects the water from further intense light.

Kawamura's team used software called the Photochemical and Radiation Transport Model to Proteus To test whether the planet would lose less water if these two factors were taken into account. The researchers calculated the water loss for an Earth-like planet with a water vapor-filled atmosphere and huge oceans. The planet orbits the dwarf star at a distance about 2% of the distance it orbits around the Sun, relative to TRAPPIST-1, shown in the featured image above. The researchers assumed that the only chemical reaction occurring in the planet's atmosphere is between hydrogen and oxygen. Kawamura and his team ran the model once to see if the results differed from previous studies and how they changed depending on the altitude of the planet's atmosphere.

The team found that the model planet's atmosphere turned out as expected: It had a very high layer of atmosphere, where starlight split water into free hydrogen and oxygen atoms, with the hydrogen escaping into space, and a layer of oxygen gas formed below, reducing the intensity of the starlight at lower altitudes, and the free hydrogen mixed with hydrogen superoxide in a chemical reaction to produce more water.

Ultimately, they calculated that the amount of water lost to space was only about seven times that of Earth's oceans. This means that even if a terrestrial planet started at the low end of the water content range, it could still have eight times as much water as Earth's oceans after its first billion years of existence. The researchers suggested that their findings imply that rather than a galaxy filled with planets with little water, like Earth, the universe could contain worlds with vast oceans orbiting dwarf stars. In other words, future humans are likely to discover Arrakis, but not Caladan. Still, they suggested that future researchers should test planetary water loss models with different atmospheric compositions, alternative cooling processes, and water trapped in the planet's rocks and magma.


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Source: sciworthy.com

Astronomers report that the moons orbiting asteroid Dinkinesh are in a contact binary configuration

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Dinkinesh is a small asteroid orbiting the Sun near the inner edge of the main asteroid belt. NASA’s Lucy spacecraft recently revealed that this asteroid, with an effective diameter of just 720 meters, is unexpectedly complex. The asteroid has a pronounced valley covered by an equatorial ridge and is currently orbited by a contact binary moon, named Seram, which consists of two nearly equal lobes with diameters of 210 meters and 230 meters. The moon orbits at a distance of 3.1 kilometers from Dinkinesh, has an orbital period of about 52.7 hours, and is tidally locked.

Stereo image pair (a-c) taken by the L’LORRI instrument aboard NASA’s Lucy spacecraft on November 1, 2023, shows asteroid Dinkinesh. Yellow and rose dots indicate valley and ridge features, respectively. These images have been sharpened and processed to enhance contrast. Image (d) shows a side-on view of Dinkinesh and its moon Ceram, taken a few minutes after closest approach. Image credit: NASA/GSFC/SwRI/Johns Hopkins APL/NOIRLab.

“We want to understand the strength of small bodies in the solar system because it’s important to understanding how planets like Earth got here,” said Dr. Hal Levison, a research scientist at Southwest Research Institute and Lucy principal investigator.

“Essentially, planets formed when a bunch of tiny objects orbiting the sun, like asteroids, collided with each other.”

“How objects behave when they collide – whether they break or stick together – has a lot to do with the object’s strength and internal structure.”

The researchers believe that how Dinkinesh responded to stress may reveal something about its inner workings.

As it rotated in sunlight for millions of years, tiny forces from thermal radiation radiating from the asteroid’s warm surface created tiny torques that caused Dinkinesh to spin gradually faster, and the accumulated centrifugal forces caused parts of the asteroid to become more elongated.

This event likely sent debris into close orbit, providing the raw material for the formation of the ridge and moons.

If Dinkinesh had been a weaker, more mobile mass of sand, its particles would have gradually migrated toward the equator and then blasted off into orbit as it rotated faster.

But the images suggest that, like rock, the Dinkinesh asteroid was stronger than a fluid and held together longer, until it eventually disintegrated under pressure and broke into larger pieces. Still, the force needed to break up a small asteroid like Dinkinesh is tiny compared to most rocks on Earth.

“This valley suggests a sudden collapse, more like an earthquake, where stress builds up gradually and then is suddenly released, rather than the slow process that creates sand dunes,” said Dr. Keith Noll, a research scientist at NASA’s Goddard Space Flight Center and a Lucy scientist.

“These features show that Dinkinesh has some strength, and we can do a bit of historical reconstruction to see how this asteroid evolved,” Dr Levison said.

“During that collapse, the rocks broke apart and things separated, forming a disk of material, some of which rained down to the surface and formed the ridge.”

“We think that some of the material in the disk formed the moon Ceram, which is actually a structure where two celestial bodies are in contact with each other, known as a contact binary. The details of how this unusual moon formed remain a mystery.”

of Investigation result Published in the journal Nature.

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H.F. Levison others2024. Contact binary moon of asteroid (152830) Dinkinesh. Nature 629, 1015-1020; doi: 10.1038/s41586-024-07378-0

Source: www.sci.news

Searching for the exomoon: Investigating a moon orbiting a distant planet

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Many years ago, at that time david kipping When he lived in London, he would walk home through the city and look up at the moon. For astronomers, its dimly glowing presence was a nightly source of inspiration. “It reminded us that satellites are waiting for us around exoplanets,” he says. “It made sense that we should look for them.”

It would be exciting to discover an exomoon, a natural satellite of a world outside our solar system. First, the moon may play a key role in determining the habitability of its host planet by dampening its wobble and promoting a stable climate, in the same way it did for Earth. there is. There may also be strange and wonderful configurations, such as a lunar ring or a moon with its own moon. But the most interesting thing is that some of them may be more suitable for life than exoplanets.

Kipping, now at Cornell University in New York, is part of a small community of astronomers exploring solar moons. At least statistics are on your side. About 5,500 exoplanets have been discovered so far, some of which may have dozens of moons. The problem is that it’s not easy to prove its existence. Two previous sightings of Kipping have been hotly debated.

But now there’s hope on the horizon, with many new ways to explore these objects, from monitoring rogue planets that have abandoned their stars to monitoring exoplanets’ gravitational wobbles. Armed with these new technologies, and new telescopes also in development, the Moon will…

Source: www.newscientist.com

Exoplanet similar in size to Earth found orbiting around star HD 63433

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Using NASA's Transiting Exoplanet Survey Satellite (TESS), astronomers have discovered an Earth-sized planet passing by the young Sun-like star HD 63433.

HD 63433d is located close to its parent star HD 63433, with two neighboring mini-Neptune-sized planets HD 63433b and HD 63433c orbiting further out. Image credit: Alyssa Jankowski.

HD 63433 is a G5V star located approximately 73 light years away in the constellation Gemini.

The star, also known as TOI-1726, is a member of the 414-million-year-old Moving Star Group in the Ursa Major constellation.

The newly discovered exoplanet HD 63433d is the third planet detected in this multi-planet system.

The discovery of two other planets — HD 63433b and HD 63433c (both mini-Neptunes) report By Astronomer in 2020.

The HD 63433d is tidally locked, meaning it has a day side that is always facing the stars and a side that is always in the dark.

The planet has an orbital period of 4.2 days and is very hot on its dayside (1,257 degrees Celsius, or 2,294 degrees Fahrenheit).

“These scorching temperatures are comparable to the lava world of: Corot-7b and Kepler-10bAnd we think the dayside of this planet may be a 'lava hemisphere,''' said the University of Florida astronomer. benjamin capistrant and his colleagues.

HD 63433d is the smallest known exoplanet less than 500 million years old.

The planet is also the closest Earth-sized exoplanet to be discovered at such a young age.

“HD 63433d is the closest planet to our solar system, orbiting a young star with a radius similar to Earth,” the astronomers said.

“This is therefore an attractive target for follow-up observations and provides an opportunity to uncover insights into the physics of atmospheric mass loss in exoplanets.”

“Between HD 63433d and the two larger planets known to date, the HD 63433 system is poised to play a key role in understanding the evolution of planetary systems during the first billion years after their formation. I am.”

The discovery of HD 63433d is paper inside astronomy magazine.

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Benjamin K. Capistrant other. 2024. TESS Search for Young and Mature Exoplanets (THYME). 11. An Earth-sized planet orbiting a nearby Sun-like host in the 400 million Ursa Majoris migration group. A.J. 167, 54; doi: 10.3847/1538-3881/ad1039

Source: www.sci.news