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NASA’s James Webb Space Telescope continues its mission to search for signs of life elsewhere in the universe. Recently, it provided the most detailed analysis of the atmosphere of exoplanet WASP-39b. Researchers were able to identify a new molecule in its atmosphere.
An exoplanet or extrasolar planet is a planet outside our solar system that usually orbits another star in our solar system. Galaxy. Also, a statistical evaluation based on data from the space telescope Kepler According to NASA, there are more planets than stars in our galaxy. That means there are over a trillion planets in our galaxy alone, many of which are in the Earth-sized range.
But WASP-39b Unlike other planets in our solar system. It is very large, about the size of Saturn, and Mercury orbits its star faster than our Sun, about 700 light years of the earth.
This exoplanet was one of the first to be observed by a space telescope James Webb When he started his regular scientific activities. The results have excited the scientific community working on extraterrestrials.
Recently, Webb’s highly sensitive instruments provided a detailed profile of WASP-39b’s atmospheric components. BeforeIncluding other space telescopes Hubble And Spitzer From NASA, only isolated materials from the atmosphere of this burning planet have been revealed. Thus, Webb detected water, sulfur dioxide, carbon monoxide, sodium, and potassium, not to mention signs of active chemistry and clouds.
Sulfur dioxide, the first detection in the atmosphere of a planet
You should know that the presence of sulfur dioxide can only be explained by photochemistry. In other words, the molecule is made from chemical reactions triggered by high-energy light from the planet’s parent star. On Earth, photochemistry is essential for life-related processes such as photosynthesis and the formation of the protective ozone layer in the upper atmosphere.
Diana Powell, NASA Hubble Fellow, astronomer at the Center for Astrophysics and lead member of the team that discovered sulfur dioxide contacted : ” The surprising discovery of sulfur dioxide finally confirms that photochemistry shapes the climate of hot Saturns. Earth’s climate is also shaped by photochemistry, so our planet has more in common with ‘hotter Saturns’ than we previously thought. “.
This discovery, along with the fact that Wasp-39b is very close to its star, allowed researchers from another group, lead author and researcher Shang-Min Tsai of the University of Oxford, UK, to study the effects of radiation from host stars on exoplanets. A paper describing the origin of sulfur dioxide in WASP-39b’s atmosphere explains: ” This is the first time we have seen solid evidence of photochemistry on exoplanets “.
A better knowledge of star-planet coupling will lead to a better understanding of how these processes affect the diversity of planets observed in the galaxy and point the way toward finding evidence of possible life on a habitable planet.
The complementarity of James Webb’s tools reveals a multitude of molecules
To see the light from WASP-39 b, Webb followed the planet as it passed in front of its star, allowing some of the star’s light to filter into the planet’s atmosphere. Different types of chemicals in the atmosphere absorb different colors of the starlight spectrum, so the missing wavelengths tell astronomers which molecules are present.
To capture a broad spectrum of WASP-39b’s atmosphere, a large international team used three different instruments on the telescope: NIRSpec (in two different observing modes), NIRISS and NIRCam. The researchers obtained transmission spectra during four passes of WASP-39b, Includes infrared wavelengths from 1 to 5 microns. They then made detailed comparisons of their findings, and produced scientifically sound conclusions.
Natalie Batalha, professor of astronomy and astrophysics at UC Santa Cruz, who leads the JWST Transiting Exoplanet Early Release science team, explains. contacted : ” Broad wavelength coverage provides a more complete picture of conditions in the atmosphere. In addition, each transit observation provides a planetary spectrum at different, but overlapping wavelengths, allowing the reproducibility of each instrument to be tested. “.
Apparently, by looking at the universe in infrared light, Webb can detect chemical fingerprints undetectable in visible light, including sodium (Na), potassium (K) and water vapor (H).2O), confirming previous observations from space and ground-based telescopes. Also, these data refine the picture of existing clouds: they are fragmented and therefore do not form a uniform cover over the planet.
Web Carbon Dioxide (CO2) at higher resolution, providing twice as much data as reported during its previous observations. Although carbon monoxide (CO) was detected, signatures of methane (CH4) and hydrogen sulfide (H2S) missing in the data. If present, these molecules occur at very low levels, an important discovery for scientists to stockpile exoplanet chemistry to better understand the formation and growth of these distant worlds.
Turn the story around
Having a detailed catalog of chemical elements in exoplanet atmospheres gives scientists insight into their relative abundances, such as carbon-oxygen and potassium-oxygen ratios. In turn, this provides insight into how this planet – and others – first formed from the disk of gas and dust surrounding the parent star.
Therefore, this chemical discovery of WASP-39b indicates a history of collisions and mergers of smaller bodies known as planetesimals. UC Santa Cruz exoplanet researcher Kazumasa Ohno, who worked on the Webb data, said the abundance of sulfur relative to hydrogen indicates the planet experienced significant accretion of those elements to the atmosphere.
She adds: ” The data also indicate that oxygen is more abundant than carbon in the atmosphere. This indicates that WASP-39 b first formed far from the central star “.
By analyzing the atmosphere of an exoplanet with such precision, the Webb telescope’s instruments have exceeded scientists’ expectations. These results attest to the ability of Webb’s instruments to perform countless missions on exoplanets of all types, including small rocky worlds like the TRAPPIST-1 system. A new way to explore distant worlds is now open.