A ‘Hot Neptune’ exoplanets has been found to contain sulfur dioxide in its atmosphere – an atmosphere that also erupts into space as the planet orbits the poles of its star in a highly inclined orbit every three and a third days.
The existence of sulfur dioxide in the atmosphere of the exoplanet, named GJ 3470b and located 96 light years BY earthwas shocked when spotted by The James Webb Space Telescope (JWST).
“We didn’t think we’d see sulfur dioxide on such small planets, and it’s exciting to see this new molecule in a place we didn’t expect, as it gives us a new way to understand how these planets formed.” sThomas Beatty of the University of Wisconsin, Madison said in a STATEMENT. “And minor planets are particularly interesting because their compositions really depend on how the planet formation process happened.”
Everything about GJ 3470b tells us that it has a fascinating and eventful history.
planets are formed in a disk of gas and dust that rotates around a plane connected to the rotation axis of a star. In ours solar systemwe can see evidence of this disc in what all the planets from mercury THE Neptune orbit in the ecliptic plane. GJ 3470b, on the other hand, follows a path inclined at 89 degrees to its cooling spin axis red dwarf star In other words, it is in an inclined orbit revolving around the poles of the star. Planets do not usually form in such orbits.
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With a mass 13.9 times greater than land massand a diameter of about 40% that of Jupiter, GJ 3470b is an inflated bag of gas. When such worlds are close to their star, astronomers call them “hot Neptunes.” GJ 3470b has an atmospheric temperature of 325 degrees Celsius (617 degrees Fahrenheit); the temperature of Neptune in our solar system is -200 degrees Celsius (–330 degrees Fahrenheit).
Current models of planet formation describe how the gas giants usually form farther from their star than rocky planets, in the cold depths where the gas is more abundant. However, GJ 3470b orbits at a distance of only 5.3 million kilometers (3.3 million miles) from its star. By comparison, Mercury, the closest planet to ours SUNorbits at an average distance of 58 million kilometers (36 million miles) from our star, although red dwarf systems typically dwarf our own solar system.
Ordinarily, we would expect GJ 3470b to have formed further away and then migrated inwards as a result of interactions with the planet-forming disk of its star. Meanwhile, scientists would normally suspect that the world would have been kicked out of the orbital plane through a gravitational interaction with another planet, or perhaps even overturning caused by a passing star.
However, the planet’s atmospheric mix suggests otherwise.
Despite JWST’s detection of molecules inside, such as sulfur dioxide, GJ 3470b’s atmosphere remains largely made of hydrogen and helium, even more so than the gas planets in our solar system—a fact distinguished by Hubble Space Telescope in 2019. So, the the explanation presented is that GJ 3470b actually formed close to its star as a rocky planet before accreting a thick atmosphere of near-pure hydrogen and helium—but, for now, that’s just a hypothesis. That’s why JWST’s discovery of sulfur dioxide is so important, because its presence could help distinguish between different theories of how the planet formed.
The discovery of sulfur dioxide came to light thanks to the fact that GJ 3470b transits its star, which allows astronomers to perform what is called “transmission spectroscopy”. As light from its parent star shines through GJ 3470b’s atmosphere, molecules in the world’s atmosphere absorb some of the starlight, leaving dark absorption lines in the star’s spectrum.
However, disentangling these absorption lines is difficult, especially for a hot Neptune that is likely to be shrouded in featureless haze.
“The thing is, everybody looks at these planets, and often everybody sees flat lines,” Beatty said. “But when we looked at this planet, we didn’t really have a flat line.”
Instead, JWST was able to confirm absorption lines from carbon dioxide, methane and water vapor, and indeed detect sulfur dioxide in the region for the first time time. This actually makes GJ 3470b the lightest and coolest exoplanet known to have sulfur dioxide in its atmosphere. Previous discoveries relate to hot Jupiter atmospheres with temperatures above a thousand degrees Celsius (1,830 degrees Fahrenheit).
“The discovery of sulfur dioxide in a planet as small as GJ 3470b gives us a more important item on the list of planet-forming ingredients,” Beatty said.
Sulfur probably started as a component in hydrogen sulfide, the team believes. However, because GJ 3470b orbits so close to its star, the ultraviolet light from the star’s body packs a powerful enough punch to easily tear apart atmospheric molecules, leading to a kind of chemical flux formed by fragmented molecular components recombining with others. ATOM and molecules. One sulfur atom combines with two oxygen atoms to form sulfur dioxide.
However, the planet’s parent star doesn’t just scatter atmospheric molecules; the hydrogen released from those molecules can be completely removed from the planet. GJ 3470b is therefore literal evaporating before our eyes, the stellar wind gradually dissipates its atmosphere ROOM, leaving behind a stream of hydrogen gas. Now, the planet has lost about 40% of its original mass.
The presence of sulfur dioxide in its atmosphere, the inclined orbit that remains unexplained, and the mass loss that is dramatically changing GJ 3470b forever are significant clues to the origin of this weird and wonderful planet, according to Beatty.
“These are important steps in the recipe that created this particular planet and can help us understand how such planets are formed,” he said.
Beatty presented the results at the 244th meeting of the American Astronomical Society on June 10, and they have been accepted for publication in the Astrophysical Journal Letters.