published by Henry Zimmerman

After nine years spent in deep space collecting data indicating that our sky is filled with billions of hidden planets, NASA's Kepler Space Telescope is running out of fuel. On October 30, 2018, NASA announced the withdrawal of the spacecraft.

NASA / JPL-CALTECH / T.Pyle Getty Images

After nine years spent in deep space collecting data indicating that our sky is filled with billions of hidden planets, NASA's Kepler Space Telescope is running out of fuel. On October 30, 2018, NASA announced the withdrawal of the spacecraft.

When we look at the stars, it's hard not to wonder what else – or even who other – could be there. The resilience of franchises like Star Trek in pop culture, let's prove that we have always believed in the possibility of a life beyond our own solar system. But it was only about 10 years ago that we were able to locate and identify these distant planets of our dreams.

Since March 2009, NASA has discovered more than 2,600 planets, including potentially habitable, thanks to the Kepler Space Telescope. Last week, after nearly a decade of searching for new planets, the Kepler eventually ran out of fuel. NASA has decided to officially remove Kepler from its current orbit, far from the Earth, on October 30, 2018.

"There is a big difference between knowing and believing," says Charlie Sobeck, former head of NASA's Kepler mission. "I think it will be Kepler's legacy: we finally know that planets are ubiquitous and that we will now learn more about them."

Sobeck has been working on the Kepler mission since 2000 and, although Kepler's hunt for the planet is now over, he sees the mission as a success and is not sad to see the spacecraft leave. "It's not an accident like a collision with a meteorite, an engine failure or something like that. We ran out of gas. We knew we were going to run out of fuel, "he says.

Now that Kepler is officially retired, NASA plans to continue researching new planets, but this time, a little closer to home. While Kepler's mission was to search for planets about 3,000 light-years from Earth, NASA launched a new satellite called Transiting Exoplanet Survey Satellite, or TESS, in April of this year to search all stars unless 100 light years from Earth.

Sobeck sees Kepler as "the burst of openness" in the ongoing research to answer the question "Are we alone?

"Without this mission, we would not have done tests, we would not have looked for planetary atmospheres," he says. "So, Kepler really opened the door to a new avenue of investigation."

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