[ti:NASA's Webb Telescope Confirms First Exoplanet]
[al:Science & Technology]
[ar:VOA]
[dt:2023-01-16]
[by:www.voase.cn]
[00:00.00]NASA's James Webb Space Telescope has made its first confirmation of an exoplanet.
[00:08.92]An exoplanet is a planet that orbits a star outside our solar system.
[00:17.42]The American space agency says the exoplanet is almost exactly the same size as Earth.
[00:27.25]Researchers from the Johns Hopkins University Applied Physics Laboratory in Maryland examined new data collected by the Webb to make the confirmation.
[00:42.33]Past observations made by another NASA telescope provided some evidence that the exoplanet existed.
[00:52.28]But the Webb's confirmation made the discovery official.
[00:59.03]The other space telescope is called the Transiting Exoplanet Survey Satellite, or TESS.
[01:08.25]TESS was launched in 2018 with the goal of discovering additional planets outside our solar system.
[01:19.47]The exoplanet has been named LHS 475 b. 
[01:26.81]The researchers said it is quite close to Earth for an exoplanet.
[01:33.46]It sits about 41 light-years away in the constellation Octans.
[01:41.02]A light-year is the distance light travels in one year.
[01:46.64]Exoplanets are difficult for telescopes to identify.
[01:52.53]One reason is that bright light from the stars they orbit can hide them.
[01:59.26]The search process includes observing drops in the light level of stars.
[02:06.67]Such drops could be caused by a planet passing, or transiting, in front of a star.
[02:15.21]Researchers said the Webb was able to confirm the existence of the exoplanet using the transiting observation method. 
[02:26.51]They said the confirmation came quickly after just two transit events.
[02:33.37]NASA has said the Webb telescope was developed to be able to provide a high level of detail in its observations.
[02:44.71]It is equipped with the latest technology to observe infrared waves.
[02:51.27]These waves are a kind of electromagnetic energy that cannot be seen with the human eye.
[03:00.05]NASA says the telescope's instruments can find infrared waves through gas and dust to observe distant objects.
[03:11.61]Jacob Lustig-Yaeger helped lead the research. 
[03:17.26]He said in a statement that the telescope data made it easy to make a clear confirmation. 
[03:25.95]"There is no question that the planet is there."
[03:30.20]The finding was recently presented at a conference of the American Astronomical Society in Seattle, Washington.
[03:41.39]Another leader of the team, Kevin Stevenson, added that he found the confirmation "impressive" because the exoplanet is small and rocky, which makes identification more difficult.
[03:59.44]Of all of NASA's operating telescopes, only the Webb is equipped to collect information on the atmospheres of exoplanets. 
[04:11.56]But in this case, the researchers said they do not have enough data to confirm what kind of atmosphere LHS 475 b has.
[04:25.49]Scientists generally use computer models and telescope data to study the atmospheres of exoplanets.
[04:36.41]Another member of the research team, Erin May, said the Webb telescope can easily identify a series of different molecules.
[04:49.06]"But we can't yet make any definitive conclusions about the planet's atmosphere," she added.
[04:58.58]While the researchers said they cannot confirm what is present in the exoplanet's atmosphere, they are very sure about what is not present.
[05:11.47]For example, LHS 475 b cannot have a thick atmosphere that is mostly methane, Lustig-Yaeger said.
[05:23.52]The team even noted it is possible that the exoplanet has no atmosphere at all. 
[05:31.61]Some of the available data suggests the exoplanet may have an atmosphere of pure carbon dioxide. 
[05:40.87]But the researchers said they plan to gather more data in future observations to help them learn about atmospheric conditions.
[05:53.33]NASA says it has so far confirmed more than 5,000 exoplanets.
[06:00.48]But Lustig-Yaeger noted that the Webb telescope is much better equipped to discover small, rocky exoplanets.
[06:11.89]He said this will likely lead to a lot more exoplanet confirmations.
[06:18.32]And, Lustig-Yaeger added, "We have barely begun scratching the surface of what their atmospheres might be like."
[06:29.75]I'm Bryan Lynn.