Using data from ESA's Extraterrestrial Planet Characterization Satellite (CHEOPS) and several other ESA and NASA missions, astronomers detected signs of extraterrestrial planets. Rainbow-like “glory effect” In the atmosphere of super-hot Jupiter WASP-76b. This effect occurs when light is reflected from a cloud composed of a completely homogeneous but so far unknown material. This “glory effect” is common on Earth, but it has only been discovered once on another planet, Venus. If confirmed, this first extrasolar glory would reveal more about the nature of this puzzling exoplanet and hold exciting lessons about how to better understand strange, distant worlds.
WASP-76b is the superhot planet Jupiter located 640 light-years away in the constellation Pisces.
First discovered in 2016, this exoplanet orbits the F-type star WASP-76 once every 1.8 days.
WASP-76b is tidally locked to its star. It takes about the same amount of time to rotate around its axis as it does to orbit its parent star.
On the day side, the planet receives thousands of times more radiation from its star than Earth receives from the Sun.
Temperatures on the dayside can exceed 2,400 degrees Celsius (4,352 degrees Fahrenheit), high enough to vaporize metals. However, nighttime temperatures are much cooler at 1,316 degrees Celsius (2,400 degrees Fahrenheit).
Here, the elements that form Earth's rocks melt and evaporate, condensing on the slightly cooler night side and creating iron clouds that drip rain of molten iron.
But astronomers have been puzzled by the apparent asymmetry, or oddity, of WASP-76b's “limbs,” the outermost regions seen as it passes in front of its host star.
“WASP-76b is being 'inflated' by the intense radiation from its star,” said Dr. Monica Rendl, an astronomer at the University of Geneva.
“That means it's 10% less massive than our cousin Jupiter, but almost twice the size.”
“The important thing to keep in mind is the incredible scale of what we are witnessing,” says ESA astronomer Dr Matthew Standing.
“WASP-76b is a very hot gas giant planet hundreds of light years away, likely raining molten iron. Despite the chaos, we detected potential signs of glory. It seems like it's an incredibly weak signal.''
In this study, the authors analyzed data from a variety of ESA and NASA missions, including CHEOPS, TESS, Hubble, and Spitzer.
CHEOPS intensively monitored WASP-76b as it passed in front of and around a Sun-like star. After making her 23 observations over three years, the data showed a surprising increase in the amount of light emanating from the planet's eastern “terminator,” the boundary where night and day meet. .
This allowed astronomers to disentangle the signal and constrain its origin.
“This is the first time that such a sudden change in the brightness of an exoplanet, its 'phase curve', has been detected,” said Dr. Olivier Demanjon, an astronomer at the Spanish Institute of Astronomical Sciences in Portugal.
“This discovery led to the hypothesis that this unexpected glow may be caused by a strong, locally anisotropic (direction-dependent) reflection, or glow effect.”
“Never before have we seen such colorful concentric rings on an extrasolar object,” said Dr Thomas Wilson, an astronomer at the University of Warwick.
“Therefore, if future studies confirm the glory of this first exoplanet, WASP-76b will be a truly unique object, providing insight into the atmospheres of distant exoplanets and how habitable they may be. It’s a beautiful tool for understanding.”
Confirmation of the glory effect means that the cloud, which is made up of perfectly spherical droplets, has lasted at least three years or is constantly replenished.
For these clouds to persist, the atmospheric temperature must also remain stable over time. This is an interesting and detailed insight into what's going on with WASP-76b.
Importantly, being able to detect such subtle wonders at great distances will teach scientists and engineers how to detect other less visible but important phenomena. For example, sunlight reflecting off liquid lakes and oceans is a requirement for habitability.
“More evidence is needed to say conclusively that this interesting 'extra light' is a rare glory,” said Dr Teresa Luftinger, project scientist for ESA's upcoming Ariel mission.
“Follow-up observations by the NIRSPEC instrument aboard the NASA/ESA/CSA James Webb Space Telescope could do just that. Or perhaps ESA’s upcoming Ariel mission will prove its existence.” We may even discover brighter colors shining from other exoplanets.”
a paper The survey results were published in a magazine astronomy and astrophysics.
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ODS demansion other. 2024. Asymmetry in the atmosphere of superhot Jupiter WASP-76b. A&A 684, A27; doi: 10.1051/0004-6361/202348270
Source: www.sci.news
