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NASA is expected to launch TESS (Transiting Exoplanet Survey Satellite), which will monitor more than 200,000 stars.
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In February 2017, NASA announced that it has discovered more new exoplanets, a finding that was expanded in December to include two more celestial objects found with the help of artificial intelligence. An exoplanet is a planet that orbits a star outside our solar system.
NASA is expected to launch TESS (Transiting Exoplanet Survey Satellite), which will monitor more than 200,000 stars for temporary drops in brightness caused by planetary transits.
Tess will look for dips in the visible light of stars, which requires that planets cross stars in our line of sight. Repetitive, periodic dips can reveal a planet or planets orbiting a star. Transit photometry, which looks at how much light an object puts out at any given time, can tell researchers a lot about a planet.
TESS scientists expect the mission will catalogue thousands of planet candidates and vastly increase the current number of known exoplanets. Of these, approximately 300 are expected to be Earth-sized and super-Earth-sized exoplanets, which are worlds no larger than twice the size of Earth.