Answer:
The Kepler space telescope has discovered over 1,000 confirmed extra-solar planets.
Explanation:
The Kepler Space Telescope is an optical instrument located in space designed to capture and study images of planets similar to Earth. It is an artificial satellite of NASA that orbits around the sun since March 2009. On October 30, 2018, due to fuel depletion, its withdrawal was announced, after nine years of operation.
To discover planets the Kepler performs the following: using a photometer that has built-in measures the brightness of the stars. When this varies, it is usually because a body that has momentarily covered the light has passed, between the Kepler telescope and the star. The telescope can deduce how far the object has been crossed and its path or orbit. This phenomenon is called the transit of a planet between its star and the observer. In this way, the Kepler space telescope has discovered over 1,000 confirmed extra-solar planets.
