An international team of astronomers has discovered seven potentially habitable exoplanets — or planets outside our solar system — that could have liquid water on their surfaces, according to a paper published today in the journal Nature.
“The discovery gives us a hint that finding a second Earth is not just a matter of if, but when,” Thomas Kutcher, associate administrator of the Science Mission Directorate at NASA Headquarters in Washington, said at a news conference today.
It is also a major step forward in answering the age-old question of “Are we alone out there?” Kutcher added.
Though it is unclear whether any of the newly discovered planets can harbor life, astronomers said all seven exoplanets could have liquid water — the key to life as we know it.
The newly discovered planets have been nicknamed “Earth’s seven sisters” and have masses similar to that of Earth’s, in addition to having rocky compositions like our planet, scientists said.
Three of the seven planets are considered to be in the habitable zone, which is the area around a star where a rocky planet is most likely to have liquid water, researchers added.