NASA's Spitzer Confirms Closest Rocky Exoplanet
This artist's concept shows the silhouette of a rocky planet, dubbed HD 219134b. At 21 light-years away, the planet is the closest outside of our solar system that can be seen crossing, or transiting, its star.
Credits: NASA/JPL-Caltech
Using NASA's Spitzer Space Telescope, astronomers have confirmed the discovery of the nearest rocky planet outside our solar system, larger than Earth and a potential gold mine of science data.