A new first in the history of space exploration
WASP-39b is an exoplanet, ie a celestial body located outside our solar system, some 700 light-years from Earth, in the constellation Virgo. It is currently at the center of attention since the James Webb Telescope detected the presence of carbon dioxide in its atmosphere. The information was officially communicated by NASA on August 25.
It is quite simply the first time in the history of humanity that this chemical compound has been discovered with certainty outside our solar system. Until then, this could not be concretely confirmed, including in 2008 when James Webb’s predecessor, the Hubble telescope, made a similar discovery in the atmosphere of an exoplanet called HD 189733b.
WASP-39b was discovered in 2011, and in 2018 water molecules were detected by Hubble and Spitzer telescopes in the atmosphere of this exoplanet, whose temperature is around 900 degrees Celsius. There would be about three times more water in its atmosphere than in that of Saturn. WASP-39b is about 1.3 times the size of Jupiter but weighs only a quarter of its mass.
James Webb’s advanced technology is decisive
James Webb’s observations of exoplanet WASP-39b are to be published in the scientific journal Nature on August 29, 2022. The presence of CO2 could be detected through one of the instruments on board the telescope: the near-infrared spectrograph. The sensitivity of the device on board the telescope allowed a detailed analysis of the atmosphere and the distinction of light variations betraying the presence of molecules such as carbon dioxide.
However, not enough to imagine a peaceful life on this exoplanet. Due to the very high average temperature, the strong presence of carbon dioxide is not necessarily favorable to the development of an environment conducive to life. But in any case, it is a superb discovery made possible by James Webb.
CO2 in the atmosphere of another planet? The Incredible Discovery of the James Webb Telescope
The famous James Webb Telescope has once again surprised NASA with an amazing discovery. Explanations.
After photographing Jupiter and galaxies 13 billion years ago, the James Webb telescope sent by NASA into space made an astonishing discovery. Indeed, on August 25, the telescope confirmed the presence of CO2 (carbon dioxide) in the atmosphere of an exoplanet.
An exoplanet located outside our solar system
As a reminder, an exoplanet is a celestial body located outside our solar system, about 700 light years from Earth, in the constellation Virgo. The exoplanet spotted by the telescope even has a name: WASP-39b. A discovery that simply amazed scientists. The reason ? This is the first time in human history that the presence of CO2 has been confirmed outside our solar system.
In 2011 and 2018, another telescope had discovered water molecules on this same exoplanet. In addition, the temperature of this exoplanet is around 900 degrees Celsius.
With WASP-39b, the James Webb Telescope paves the way for archaeologists of the Universe
The first observations of an exoplanet’s atmosphere by the James Webb Space Telescope, published on Thursday, revealed the presence of CO2 around WASP-39b. This first detection of this chemical compound outside our solar system confirms that the telescope will make it possible to understand the formation of the most distant planets.
Humanity had so far never detected any outside our solar system. At least not in a certain way. The observations of the James Webb space super-telescope (JWST) brought, Thursday, August 25, the definitive proof. For the first time, carbon dioxide has been detected in the atmosphere of an exoplanet (i.e. outside the solar system).
The giant eye of the brand new telescope, launched on December 25, 2021, turned to the near vicinity of our galaxy to look for traces of CO2. He found some around the planet WASP-39b which is “only” some 700 light years from Earth. It is only a few stardust blocks away from us compared, for example, to the CEERS-93316 galaxy that the James Webb instrument detected in early August more than 13 billion light-years from the Earth.
The first tool capable of “seeing” CO2 in the atmosphere
“We suspected that we would eventually find CO2, but it’s always good to have confirmation that the JWST does indeed allow us to identify this important molecule in the atmosphere of an exoplanet”, says Hannah Wakeford, astrophysicist at the University of Bristol, member of the international research team that wrote the conclusions drawn from the observation of WASP-39b, which will be published in the journal Nature, on August 29.
The Hubble telescope, predecessor of the James Webb, had already made it possible to observe in 2008 what looked like CO2 in the atmosphere of an exoplanet, but “it was only a single clue that suggested the presence of the carbon dioxide”, notes Jérémy Leconte, astrophysicist at the University of Bordeaux who was also a member of the team that carried out the observations of WASP-39b. “There, when we saw the readings transmitted by JWST, there was no possible doubt,” he adds.
“Until now, we simply did not have the tools to detect the presence of CO2 with certainty,” explains Hannah Wakeford. The JWST is, in fact, the first space observation instrument to be able to detect certain wave frequencies in the infrared. And it is precisely in this zone that the carbon dioxide blocks the light. “Each molecule will absorb light in a different way, which gives it a particular signature on the readings of the telescope”, details Jérémy Leconte.
And this is not only the first time that CO2 has been detected in the atmosphere of an exoplanet. It is also the first confirmation of the presence of this molecule on a planet of the WASP-39b type, that is to say a gas giant similar to Jupiter, all galaxies combined… including our solar system. It has, in fact, never been able to prove that there were any on Jupiter or Saturn.
CO2, a “poor indicator of the presence of life in space”
Seen from Earth, this discovery of carbon dioxide on WASP-39b could easily give rise to fantasies of the presence of life. This is because on our planet, CO2 emissions into the atmosphere generally come from living things. They can be produced during the decomposition of organic matter or come from animal respiration.
But that the hunters of extra-terrestrial arrange their net with small green men. “The presence of CO2 in a planet’s atmosphere is, in fact, a very poor indicator of the presence of life,” says Hannah Wakeford. The atmosphere of Venus, for example, is saturated with carbon dioxide even though it is a planet particularly hostile to all forms of life, if only because of the very high surface temperature ( over 400°C).
WASP-39b also experiences extreme temperatures, approaching 900°C, in its atmosphere. Where does the CO2 come from? “It is the result of a chemical reaction when you mix carbon, hydrogen and helium – all elements present in the atmosphere of this exoplanet – at very high temperatures”, underlines Jérémy The tale.
The holy grail for space archaeologists
The detection of CO2 is nonetheless essential for astrophysicists because “it is a very good indicator for understanding the history of a planet”, notes Hannah Wakeford. The presence of this molecule provides, first of all, “a serious indication that the planet has an atmosphere”, which is far from being the case for all the planets of the Universe (in our own solar system, Mercury has no atmosphere). And the atmosphere keeps the chemical traces of all the history of the planet.
Thus, the data transmitted by JWST on the atmosphere of WASP-39b – and in particular the CO2 concentration – already make it possible to make a first observation: this planet comes from elsewhere. Indeed, it is currently very close to its star – quite similar to our sun, according to the experts interviewed – and “it is physically impossible that by staying there it could have amassed so much CO2 and oxygen in its atmosphere”, assures Hannah Wakeford. For her, there are not 1001 possibilities: WASP-39b “recovered elements of CO2 and oxygen while moving from its place of formation to its current position”. Now remains to know where it comes from.
These first observations by the JWST of the atmosphere of an exoplanet have made it possible to confirm “that it is really possible to carry out this kind of detection and to find molecules like CO2“, enthuses Jérémy Leconte. In this regard, this device is indeed, for Hannah Wakeford, the long-awaited Holy Grail of space archaeology. With a very “terra-centric” approach, since the goal will be with JWST to multiply the sites on tens and hundreds of exoplanets to understand their formations and, ultimately, to know how unique our Earth is in the Universe.
The James-Webb telescope detects CO2 in the atmosphere of an exoplanet
The James-Webb Space Telescope has detected carbon dioxide molecules in the atmosphere of an exoplanet, NASA announced Thursday, August 25. The hitherto unequaled capabilities of the device give hope for new discoveries to come.
The discovery delighted the scientific community. NASA announced on Thursday August 25 that the James Webb Space Telescope had detected traces of CO2 in the atmosphere of WASP-39b, an exoplanet located 700 light years from Earth.