It is located 40 light years from our solar system
Wednesday – 7 Ramadan 1444 A.H. – March 29, 2023 A.D. Issue Number [16192]
Paris – London: «Asharq Al-Awsat»
In a process conducted for the first time ever, the James Webb Space Telescope succeeded in measuring the temperature of a rocky planet located 40 light-years from our solar system, according to Agence France-Presse.
The TRAPPIST-1 system, discovered in 2017, includes seven planets orbiting a supercool red dwarf star, which emits twice as much heat as the Sun.
This planetary system is a major target of the “James Webb” telescope, which was developed by the US Space Agency (NASA) and put into service in July 2022. One of the telescope’s tasks is to explore the atmosphere of potentially habitable exoplanets.
And “NASA” stated, in a statement, that “(TRAPPIST-1) is an excellent planet for testing,” as it is close to the solar system and includes only rocky planets similar in size and mass to Earth.
However, knowing the characteristics of these planets is a difficult issue because it is not possible to observe the outer planets from a great distance, in contrast to the stars that revolve around them. To observe it, astronomers resort to a method that consists in capturing differences in the brightness of the planet caused by it passing in front of its host star, similar to what happens in a small eclipse.
James Webb’s Merim imaging device, which is capable of operating in the mid-infrared wavelength, captured what is called a secondary eclipse when the planet passes behind its star. In this case, the planet is “TRAPPIST-1b” closest to the star “TRAPPIST-1”, which is easy to study because it crosses a lot behind the star.
Elsa Ducro, an astrophysicist at the Commission for Atomic Energy and Alternative Energies, who co-authored the study published in the journal Nature, explains that “the planet’s greatest brightness occurs moments before it disappears behind the star because it shows its daytime side almost exclusively.”
By comparing the amount of light observed before and after the planet disappeared behind its star, scientists concluded the amount of light emitted by the planet, which can only be observed in the mid-infrared wavelength, a wavelength that astronomers have not explored until today, and would detect the planet’s thermal emission. . And NASA, in which one of its astronomers, Thomas Green, prepared the study, commented that James Webb works as a giant non-contact thermometer.
Measuring the temperature of TRAPPIST 1b is the first such operation for a rocky exoplanet. The temperature on the day side of the planet was about 230 degrees Celsius, an indication that the heat was not redistributed throughout the planet, a role usually played by the atmosphere, according to the Commission for Atomic Energy and Alternative Energies, which designed the “Merim” device.
And Ducron says, the conclusion is, therefore, that the planet “Trapist 1b” “has little or no atmosphere,” stressing the need to search in other wavelengths to reach a final result. And she added, “As for what is certain, it is that the atmosphere, even if it is present in the planet, lacks carbon dioxide.”
The discovery of “James Webb” carries details of the failure of a previous telescope, “Spitzer”, to reach it, “despite the observation of 28 secondary eclipses of (TRAPPIST – 1b)”. And the scientist says, “(James Webb) deduced these details by observing one eclipse!”
She pointed out that “James Webb”, through his study of the possibility of an atmosphere in a rocky planet, launches a “new phase” in the study of exoplanets.
Trappist 1b is located so close to its star that it could house life as we know it. Its monitoring process may provide important information about other planets, according to NASA.
Among these planets are “TRAPPIST-1i”, “TRAPPIST-1F” and “TRAPPIST-1G”, which are located in a habitable zone, which is an area that is not very hot or cold, which allows the formation of liquid water in it, which is a prerequisite for life. extraterrestrial.