Kepler Space Telescope retires after almost a decade of hunting planets

NASA announced the termination of the mission of the Kepler space Observatory, almost 10 years after its launch.

Kepler focused on stars thousands of light-years away and, according to NASA, showed that statistically there's at least one planet around every star in our Milky Way Galaxy. "Now that we know planets are everywhere, Kepler has set us on a new course that's full of promise for future generations to explore our galaxy".

The most recent analysis of Kepler's discoveries concludes that 20 to 50 percent of the stars visible in the night sky are likely to have small (possibly rocky) exoplanets similar in size to Earth.

Kepler was succeeded by NASA's Transiting Exoplanet Survey Satellite, or TESS, which was launched in April.

"Basically, Kepler opened the gate for mankind's exploration of the cosmos", Kepler's now-retired chief investigator William Borucki said.

NASA's legendary Kepler space telescope, which is responsible for the discovery of thousands of freaky and intriguing exoplanets, has officially run out of fuel. NASA has made a decision to retire the spacecraft, letting it continue its current orbit around the sun for eternity. It is a possible "water world" the size of Earth perhaps covered with oceans and with a water-based atmosphere.

Working in deep space for nine years, Kepler discovered planets from outside the solar system, many of which could be promising places for life.

Several of them are rocky and Earth-sized in the so-called Goldilocks or habitable zone of a star - an orbit where temperatures are neither too cold nor too hot, but just right for the existence of water, which is considered a key ingredient for life.

Jessie Dotson, Kepler project scientist at NASA's Ames Research Center, said, "I guess I feel like it was the little spacecraft that could".

Four years into the mission, after the primary mission objectives had been met, mechanical failures temporarily halted observations. Over the life of the mission, more than 100,000 of those stars were actively monitored by Kepler.

The end of spacecraft operations means the end of new Kepler data, but project scientists said that the observations Kepler collected since its March 2009 launch will continue to be analyzed by astronomers for years to come, yielding new discoveries. In 2014, NASA announced the K2 "Second Light" extension, which increased the telescope's surveyed star count to more than 500,000. It's also illuminated the tantalizing mysteries and possibilities among the stars. Kepler watched the very beginning of exploding stars, or supernovae, to gain unprecedented insight about stars and witnessed the death of a solar system. As of October 29, Kepler had detected 2,681 exoplanets, with an additional 2,899 exoplanet candidates awaiting confirmation, said Jessie Dotson, Kepler project scientist at NASA Ames.

In a briefing with reporters, agency officials said that Kepler ended operations after exhausting the last of its hydrazine fuel used for attitude control.

A marvel of engineering The $600 million Kepler mission found alien worlds using the "transit method", picking up on tiny brightness dips caused when orbiting planets cross a star's face - as seen from Kepler's perspective.

"That's the path Kepler has put us on", said Paul Hertz, astrophysics division director at NASA Headquarters in Washington. "I'm excited about the diverse discoveries that are yet to come".