When Kepler was still being brainstormed by NASA 35 years ago, there was no proof of any planets beyond our solar system.
Since it was launched in 2009, Kepler has aided astronomers around the world in the hunt for planets outside of the solar system similar to Earth and orbiting other stars. Meaning it found more planets lurking out there than even stars.
"Its discoveries have shed a new light on our place in the universe, and illuminated the tantalizing mysteries and possibilities among the stars", he added. The spacecraft discovered planets in all shapes and sizes and groupings.
"Not only did it show us how many planets could be out there, it sparked an entirely new and robust field of research that has taken the science community by storm", Zurbuchen said.
"The Kepler mission was based on a very innovative design".
"Now, that we know there are exoplanets everywhere, Kepler Space Telescope has put us on a new path full of promise for future generations to explore our galaxy", Kepler principal investigator William Borucki, founder of the Kepler Space Telescope mission, said in the statement. Many have planets, and sometimes multiple planets, orbiting within the habitable zone of their host star, where liquid water may exist on their surfaces.As with any mission, the Kepler package came with trade-offs.
But the mission was not without its hiccups - in 2013, mechanical failures stopped Kepler's observations.
"The search for exoplanets using the Kepler data is still underway. It was an extremely clever approach to doing this kind of science", says director for astronomy and physics at NASA's Jet Propulsion Laboratory, Leslie Livesay.
This image was spotted as part of Hubble mission to better understand how new stars are born. While spacecraft operations have ceased, its data will continue to be publicly available through the Mikulski Archive for Space Telescopes (MAST) at the Space Telescope Science Institute. Many of these planets could be promising places for life. As for Kepler itself, it has far outlived its original four-year mission, and its passing is an opportunity to reflect on its success. Now, however, the spacecraft has run out of its hydrazine fuel and officially entered retirement.
Kepler was succeeded by NASA's Transiting Exoplanet Survey Satellite (TESS), which was launched in April for a two-year, $337 million (€295 million) mission. The James Webb Space Telescope (JWST), whose launch has been delayed to 2021, will be capable of studying the atmospheres of planets discovered by TESS and identifying their chemical compositions.