TEMPO.CO, Jakarta - Scientists revisit the mystery of space by discovering 10 Earth-like planets. With the discovery of the planets, a total of 219 exoplanets or planets outside our solar system have the conditions for life.

The ten planets were found using the Kepler space telescope of the US space agency (NASA). Scientists found it among the 200 thousand samples of stars in the constellation Cygnus.

A total of 10 rocky planets are found orbiting the star with a distance that allows for the planets to contain water. According to scientists, water is the key to life.

"The question now is whether humans are alone in the universe?" "Kepler team scientist Mario Perez told Reuters news agency on Tuesday, August 22, 2017. "It's possible that Kepler is telling us that we are not alone."

NASA launched Kepler telescope in 2009. One of its tasks is to study planets like Earth. For four years, Kepler has revealed 2,355 planets and 1,699 would-be planets.

Perez explains, Kepler presents a new method in analyzing the surface of the planet. So, scientists can be helpful to determine whether the planet has a rocky surface like earth or gas like Neptune.

REUTERS | AMRI MAHBUB