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Source: The post is based on the article “James Webb telescope discovers its first Earth-sized exoplanet: What are exoplanets?” published in Indian Express on 18th January 2023.
What is the News?
NASA’s James Webb Space Telescope has discovered its first new exoplanet named- LHS 475 b.
What is the James Webb Space Telescope?
What is LHS 475 b?
LHS 475 b is an exoplanet. It is roughly the same size as Earth.
Located just 41 light-years away, the planet orbits very close to a red dwarf star and completes a full orbit in just two days.
What are Exoplanets?
Exoplanets are planets that orbit other stars and are beyond our solar system. According to NASA, to date, more than 5,000 exoplanets have been discovered.
Exoplanets come in a host of different sizes. They can be gas giants bigger than Jupiter or as small and rocky as Earth. They are also known to have different kinds of temperatures — boiling hot to freezing cold.
How are exoplanets discovered?
Discovering exoplanets is quite tough as they are small and hard to spot around their bright host stars. Scientists rely on indirect methods, such as the transit method which is measuring the dimming of a star that happens to have a planet pass in front of it.
Why should one need to study exoplanets?
Studying exoplanets not only broadens human understanding of other solar systems but also helps us piece together information about our own planetary system and origin.
However, the most compelling reason to learn about them is to find the answer to one of the most profound and thought-provoking questions of humankind — are we alone.
Another important element of the study is finding out the distance between an exoplanet and its host star. This helps scientists determine if a discovered world is habitable or not.
When a planet is at a distance that enables it to have liquid water, it is said to be in the “Goldilocks zone” or the habitable zone.
What are Red Dwarf Stars?
Red Dwarf Stars are the most common and smallest in the universe. As they don’t radiate much light, it’s very tough to detect them with the naked eye from Earth.
However, as red dwarfs are dimmer than other stars, it is easier to find exoplanets that surround them. Therefore, red dwarfs are a popular target for planet hunting.
