Exoplanet Discovery: Latest Findings and Technology Used by Webb Telescope
NASA's James Webb Space Telescope's Near-Infrared Spectrograph (NIRSpec) captured a spectrum of exoplanet LHS 475 b on August 31, 2022, revealing a featureless spectrum with no detectable elements or molecules. The white dots in the image represent the collected data, while the yellow line indicates the planet's atmosphere with no features. The green line shows a pure methane atmosphere, but it's not likely since it would have blocked more starlight at 3.3 microns. The purple line, representing a pure carbon dioxide atmosphere, is indistinguishable from a flat line at the current level of precision. Credits: NASA/ESA/CSA et al
March 19, 2023
The discovery of exoplanets, planets beyond our solar system, has fascinated astronomers for decades. The possibility of finding other worlds that might be habitable or harbor extraterrestrial life has driven research and innovation in the field of astronomy. The James Webb Space Telescope (JWST), launched in December 2021, is expected to revolutionize our understanding of exoplanets and their atmospheres. In this article, we'll explore some of the latest exoplanet discoveries and the technologies used to make them, with a focus on the JWST.
The Kepler Mission, launched in 2009, was a game-changer in exoplanet research, identifying thousands of exoplanets orbiting distant stars. However, the Kepler data was limited in scope, and the JWST is expected to take exoplanet discovery to the next level. With its advanced instrumentation and infrared capabilities, the JWST will be able to observe exoplanets in greater detail than ever before. It will also be able to study exoplanet atmospheres, allowing scientists to search for signs of life on distant worlds.
One of the most exciting recent exoplanet discoveries was made by the Transiting Exoplanet Survey Satellite (TESS), a NASA mission launched in 2018. TESS uses the transit method, observing stars for the slight dimming that occurs when a planet passes in front of them. In February 2021, TESS identified a rocky exoplanet called TOI-1233 b orbiting a nearby M-dwarf star. TOI-1233 b is only 90 light-years away, making it one of the closest exoplanets ever discovered. It has a mass similar to Earth's and a surface temperature of around 350 degrees Celsius.
Another recent exoplanet discovery was made by the CHEOPS (CHaracterising ExOPlanet Satellite) mission, a collaboration between the European Space Agency and Switzerland. CHEOPS is designed to study exoplanets that have already been identified and to provide more precise measurements of their characteristics. In February 2021, CHEOPS observed the exoplanet WASP-189 b, a gas giant orbiting a star 1,800 light-years away. WASP-189 b is one of the hottest exoplanets ever discovered, with a surface temperature of around 3,200 degrees Celsius.
While these discoveries are exciting in their own right, they are just a taste of what the JWST is expected to uncover. The JWST will be able to observe exoplanets in the infrared spectrum, allowing scientists to study their atmospheres in detail. This will provide important information about the composition of exoplanet atmospheres and whether they contain gases that could indicate the presence of life. The JWST will also be able to study the atmospheres of exoplanets that are similar in size and composition to Earth, providing insights into the potential habitability of these worlds.
The technologies used in the JWST are cutting-edge, including a 6.5-meter primary mirror made up of 18 hexagonal segments that can be adjusted individually. The mirror will be able to capture more light than any previous space telescope, allowing the JWST to observe faint and distant objects in the universe. The JWST is also equipped with four scientific instruments, including the Near Infrared Camera (NIRCam) and the Near Infrared Spectrograph (NIRSpec), which will enable it to observe exoplanets in unprecedented detail.