Mission scientists anxious that the spacecraft may have been irreparably rendered ineffective after the steering malfunction in 2012, though they eventually came up with an ingenious solution in 2013 using pressure generated by the sun's rays to compensate for a failed reaction wheel and aim it at observation targets. The spacecraft is in a safe orbit far from Earth.
Its findings indicate that billions of distant star systems are teeming with planets - perhaps trillions in the Milky Way galaxy alone.
Its positioning system broke down in 2013, though scientists found a way to keep it operational.More news: 7 dead in attack on bus carrying Coptic Christians in Egypt
"While this may be a sad event, we are by no means unhappy with the performance of this marvelous machine", Charlie Sobeck, project system engineer at NASA's Ames Research Center in California, told reporters on a conference call. Originally only created to operate for around three and a half years, the spacecraft ultimately spent over nine and a half years in operation. That number includes about 50 that may be about the same size and temperature as Earth.
NASA Astrophysics Division Director Paul Hertz made the announcement during a teleconference today that included Bill Borucki, Kepler's principal investigator.
During the first years of Kepler's operations, the telescope was extremely successful.More news: Why Ariana Grande Is ''Hurt'' by Pete Davidson's SNL Split Joke
A series of huge new terrestrial telescopes now under construction will also be able to analyze exoplanet atmospheres spectroscopically, and look for signs of life such as the presence of oxygen gas and water vapor. During its time, it discovered 2,600 planets.
All the data Kepler collected has now been safely returned to Earth. Kepler also found nature often produces jam-packed planetary systems, in some cases with so many planets orbiting close to their parent stars that our own inner solar system looks sparse by comparison. TESS has just begun its survey of nearly the entire night sky, looking for exoplanets orbiting some of the brightest and closest stars. TESS is on a two-year, $US337 million mission. It also unveiled incredible super Earths: planets bigger than Earth but smaller than Neptune. It found inferno-like gas giants, rocky planets, planets orbiting binary stars, Earth-size planets, planets in the habitable zone capable of supporting liquid water on the surface, planets twice the size of Earth, the strangely flickering Tabby's Star, new details about the TRAPPIST-1 planetsand, in December, an eight-planet system.
The far more advanced James Webb Space Telescope, scheduled to lift off in 2021, should be able to reveal more about planets' mass, density and the makeup of their atmosphere - all clues to habitability. Originally positioned to stare continuously at 150,000 stars in one star-studded patch of the sky in the constellation Cygnus, Kepler took the first survey of planets in our galaxy and became the agency's first mission to detect Earth-size planets in the habitable zones of their stars.More news: Shah Rukh Khan celebrates 53rd birthday with family, fans