Tag Archives: carbonrich

Webb Observations Reveal TOI-5205b: A Carbon-Rich, Oxygen-Poor Atmosphere of a Giant Exoplanet

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Astronomers have utilized the Near Infrared Spectrometer (NIRSpec) on the NASA/ESA/CSA James Webb Space Telescope to analyze the atmosphere of TOI-5205b, an extrasolar gas giant orbiting a dim red dwarf star. These groundbreaking observations reveal that the atmosphere is surprisingly deficient in heavy elements, raising intriguing questions regarding the formation and evolution of such “forbidden” alien worlds.

The Jupiter-sized planet TOI-5205b has a surface temperature of 737 K and orbits at a distance of 0.02 astronomical units from its parent star, TOI-5205. Image credit: Sci.News.

TOI-5205b is a short-period gas giant with only 1.03 times the radius and 1.08 times the mass of Jupiter, completing its orbit in just 1.63 days.

Discovered in 2022, this planet orbits the TOI-5205, an M4-type star with approximately 39% of the Sun’s size and mass.

The system, also known as TIC 419411415, is located about 283 light-years away in the constellation Vorissa.

“Short-period Jupiter-mass planets are among the first exoplanets found around Sun-like main-sequence stars, yet their formation processes are still not fully understood,” explained Dr. Caleb Cañas from NASA’s Goddard Space Flight Center.

“The increasing number of short-period giant exoplanets around M dwarfs adds further complexity to gas giant planet formation theories.”

“These worlds are challenging to form through nuclear accretion due to the low disk masses and longer orbital time scales of M dwarfs, which hinder the efficient creation of massive planetary cores necessary for runaway gas accretion.”

“These planets exemplify an extreme formation regime for mid-to-late M-type dwarfs since the significant planet-to-star mass ratio demands a core mass exceeding the estimated dust mass of the protoplanetary disk.”

Astronomers used Webb’s NIRSpec to observe three separate transits of TOI-5205b.

To their surprise, they discovered that the concentration of heavy elements in the planet’s atmosphere, relative to hydrogen, is lower than found in the gas giants of our solar system, including Jupiter. Remarkably, it is even less metallic than its host star.

This finding sets TOI-5205b apart from all other studied giant planets.

Furthermore, the observations revealed the presence of methane and hydrogen sulfide in the planet’s atmosphere, corroborating previous findings.

To better understand their results, the researchers employed an advanced model of the planet’s interior, predicting that TOI-5205b’s overall composition is about 100 times richer in metals than its atmosphere.

“We observed a significantly lower metallicity than what models predicted for the planet’s bulk composition, based on measurements of its mass and radius,” noted Dr. Shubham Kanodia of Carnegie Science.

“This suggests that heavy elements migrated to the interior during formation, indicating that the interior and atmosphere are not currently mixing.”

“In essence, our findings imply that the planet’s atmosphere is notably carbon-rich and oxygen-poor.”

For more information on these findings, check out the latest publication in Astronomy Magazine.

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Caleb I. Cañas et al. 2026. GEMS JWST: TOI-5205b’s transmission spectroscopy reveals significant contamination of the star and a metal-poor atmosphere. A.J. 171, 260; doi: 10.3847/1538-3881/ae4976

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

A carbon-rich dust shell near Wolf Raye 140 has been found by Webb

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Wolf Rayet 140 (also known as WR 140 or HD 193793) is a system of two massive stars located approximately 5,000 light-years away in the constellation Cygnus. As these stars swing against each other, the stellar winds from each collide, compressing material and forming carbon-rich dust. New observations from the NASA/ESA/CSA James Webb Space Telescope show that 17 dust shells glowing in the mid-infrared are expanding into the surrounding space at regular intervals.

This image of the carbon-rich Wolf-Rayet star WR 140 was taken by the Webb Mid-Infrared Observer (MIRI) in September 2023. Image credits: NASA / ESA / CSA / STScI / E. Lieb, University of Denver / R. Lau, NSF's NOIRLab / J. Hoffman, University of Denver.

“Webb confirmed that Wolf-Rayet 140's dust shell is real,” said Emma Reeve, a doctoral student at the university. “We have shown that there is a visible change in an incredibly short period of time.” Originally from Denver, Colorado.

“All of the shells are moving away from the star at more than 2,600 kilometers per second, which is almost 1% of the speed of light.”

“We're used to thinking of events in the universe as happening slowly over millions or billions of years,” said Jennifer Hoffman, a professor at the University of Denver.

“In this system, the observatory shows that the dust shell is expanding year by year.”

Dr Olivia Jones, an astronomer at the UK Astronomical Technology Center, said: “It's truly amazing to see the real-time movement of these shells during the Webb observations, which were made just 13 months apart.” Ta.

“These new results provide the first glimpse of the potential role of such giant binary stars as dust factories in the universe.”

Like clockwork, the star's winds generate dust for a few months every eight years. The pair approaches each other in a wide and long orbit.

The web also shows where dust stops forming. Look for the dark area in the top left of the image.

The telescope's mid-infrared images detected shells that have survived for more than 130 years. The old shells have dissipated enough that they are now too dark to detect.

Astronomers estimate that a star will eventually produce tens of thousands of dust shells over hundreds of thousands of years.

“The dust in this system is quite cold, so mid-infrared observations are absolutely critical to this analysis,” said Dr. Ryan Lau, an astronomer at the NSF NOIRLab.

“Near-infrared and visible-light observations only show the shells closest to the star.”

“With these amazing new details…
findings Published in Astrophysics Journal Letter.

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Emma P. Reeve others. 2025. Dynamic signature of dust formation due to wind impact from WR 140. APJL 979, L3; doi: 10.3847/2041-8213/ad9aa9

Source: www.sci.news