Is There Life on WASP-39b?
NASA’s James Webb Space Telescope (JWST) has captured conclusive evidence for CO2 in the atmosphere of WASP-39b, a gas giant planet orbiting a Sun-like star 700 light-years away. WASP-39b, a gas giant planet orbiting a Sun-like star 700 lin light-years away.
In late August, the exoplanet WASP-39b, orbiting a star in the constellation Virgo made news when James Webb Space Telescope found carbon dioxide in the planet’s atmosphere. In addition, Webbs space telescopes have detected carbon dioxide, carbon monoxide, sodium, potassium, and water vapor in the distant exoplanet’s gargantuan atmosphere. Previous observations by other telescopes, including NASA’s Hubble and Spitzer space telescopes, have revealed water vapor, sodium, and potassium in the WASP-39bs atmosphere.
The new data provide the first indication in the exoplanet’s atmosphere of sulfur dioxide, a molecule produced in chemical reactions caused by a distant planet’s host star and its high-energy light. The high sulfur abundance [relative to] hydrogen indicates a distant, massive exoplanet is likely experiencing a substantial planetesimal accretion event capable of transporting [these ingredients] into its atmosphere. The amount of sulfur relative to hydrogen, for instance, suggested that a distant gas giant exoplanet formed by the fusion of a number of smaller bodies, each of which brings its own ingredients to the atmosphere, according to Kazumasa Ohno, a research fellow at UC Santa Cruz.
The results indicate that an exoplanet has taken up large amounts of water in ice, likely while it was at another location, and formed far outside of our solar system, possibly compared with the position when Jupiter was orbiting the sun, says Eve-Maria Ahrer, an astronomer at the University of Warwick, U.K., and the main author on one of the papers3. Also, a lower ratio of carbon to oxygen in WASP-39bs clouds suggests it was likely located further from its star than today (or, more precisely, 700 years ago, given its light-year distance), likely absorbing a higher quantity of water as ice, likely absorbing a higher quantity of water as ice, when it was in the vicinity of the Sun. Astronomers have also analyzed the ratio of oxygen to carbon in WASP-39bs exoplanet clouds, concluding that this large abundance could be explained only by the planet being formed further from its star than it is.
To view light coming from the exoplanet WASP-39b, Webb tracked the planet as it passed in front of its star, allowing some of its light to filter through the planet’s atmosphere. The WASP-39 b discovery was made by detecting, at ground level, the faint, periodic dimming of the star G-type light when the planet transited, or passed in front, of the star. WASP-39’s closeness to its host star — closer than Mercury is to our sun — also makes it perfect for studying the effects of the host’s radiation on the exoplanet.
The distant planet is an exoplanet — a planet beyond our solar system — that is about the same mass as Saturn but is far closer to its host star, which makes it possible to measure an estimated 1,600 degrees Fahrenheit (871 degrees Celsius) in temperatures coming out of its gases, according to NASA. WASP-39b, though, is a less likely candidate for hosting alien life because the planet’s temperature skyrockets to an unbearable 1,650 degrees Fahrenheit (900 degrees Celsius) because of its closeness to its host star. The discovery centers on an exoplanet about the size of Jupiter called WASP-39b, which, being eight times closer to its star than Mercury is to the sun, is blisteringly hot at about 1,600 degrees Fahrenheit (900 degrees Celsius).
Observations of the planet WASP-39b revealed a patchy atmosphere and intriguing chemical reactions and provided clues to exoplanet formation. Although a distant, massive exoplanet is too distant to be imaged directly or to reveal much detail, new analyses by Webb also suggest how its clouds might look.
The data suggests to researchers that chemicals in a planet’s atmosphere might be broken down into clouds instead of distributed uniformly across a planet’s toxic atmosphere. The Webb Space Telescope captures the star’s infrared wavelengths, and scientists can infer what chemicals are in the atmosphere by examining what wavelengths of light they absorb.
Different molecules in a planet’s atmosphere absorb different wavelengths of the star’s light. Astronomers can say which molecules are present simply by looking at what wavelengths are missing as filtered light arrives at Earth. Different types of chemicals in that blazing planet’s atmosphere absorb different colors of the star’s light spectrum, so what colors are missing tells astronomers which molecules are present. Because different types of molecules block out different wavelengths of light, by looking at what wavelengths are missing as the exoplanet passes past its star, astronomers can also tell what types of molecules are present in its atmosphere.
Having such a comprehensive list of the chemical ingredients in an exoplanet’s atmosphere also gives scientists an idea of how abundant various elements are relative to one another, like carbon-to-oxygen ratios or potassium-to-oxygen ratios. These measurements, like carbon-to-oxygen and potassium-to-oxygen ratios, could provide researchers with insight into how a single exoplanet formed from a disc of gas and dust surrounding a star 700 light-years away during its youngest years. By measuring the carbon dioxide in the atmosphere of a gas giant, astronomers can find out how much gaseous (as opposed to solid) material went into the planet’s formation.
This marks the first detection of sulfur dioxide in an exoplanet’s atmosphere, and its presence suggests the light of its star is driving chemical reactions in a distant gas giant exoplanet’s atmosphere — a process similar to the one that produces our Sun’s ozone layer. Now, the JWST Transiting Exoplanets team has identified the molecule responsible as sulfur dioxide and determined that it is produced through photochemistry: chemical reactions in an atmosphere driven by the light of a planet’s host star, similar to how the Earth’s atmosphere produces ozone through photochemical reactions.
From the end of July of this year, the JWST tracked four transits of WASP-39b and, using a process known as Transmission Spectroscopy, observed the light of the planet’s star as it filters through its atmosphere, picking up the chemical fingerprints of molecules found there. The telescope’s suite of high-sensitivity instruments was trained on the atmosphere of the hot Saturn, a planet roughly the mass of Saturn that orbits a star some 700 light-years away, known as WASP-39b.
