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.
“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
