This morning, NASA announced a big discovery made in Kepler's planet-hunting mission — what it's calling Earth 2.0, or Earth's older cousin.
The planet, technically named Kepler-452b, is Earth-like but actually much larger than Earth by 60 percent in diameter. It lives in what NASA calls the habitable zone, an area where water could form on the planet, while surrounding a star that is similar to Earth's sun. NASA is calling it Earth 2.0 not only because it exists around this star but because it's 6 billion years old — which is older than Earth and gives plenty of time for possible life to form on the planet.
What you see up top is an artist's concept comparing Earth (left) to Kepler-452b (right). Below is another artist concept depicting one possible appearance of Kepler-452b.
The Kepler mission from 2009 to 2013 that made this discovery also found 4,696 more planet "candidates." Next steps include analyzing the data, which will be used to accurately decide whether or not these are actual planets. Of these candidates, 12 are similar to the size of Earth and exist in the habitable zone. Nine of these planets also orbit around stars like our sun. However, because of age, none are as promising as the Kepler-452b.
NASA said this discovery will help to answer questions like, "Where are we going as humans?" and, more importantly, "Are we alone in the universe?"
"It's a small step in answering that question today," said John Grunsfeld, NASA's associate administrator for the Science Mission Directorate. We'd argue that it's a big one.