n. A planet outside our solar system that is approximately the same size as the Earth and roughly the same distance from its star.
2011
Astronomers are probably just a few years from the first-ever finding of an Earth twin outside our solar system, that is, a planet roughly the size of Earth orbiting at a similarly temperate distance from a sunlike star.
2011
Slightly smaller than Earth, KOI 326.01 lies in the habitable zone of its star, a red dwarf star dimmer than our sun. At around 100 light years away, it's "fairly close" to us, said William Borucki, of NASA's Ames Research Center, "but they're not places you can walk to on a Sunday".
Currently just a promising data point, KOI 326.01 (which stands for Kepler Object of Interest) might end up getting a better name if it does turn out to be a real Earth twin.
Currently just a promising data point, KOI 326.01 (which stands for Kepler Object of Interest) might end up getting a better name if it does turn out to be a real Earth twin.
1993 (earliest)
The "Earth twin distance" is how far a planet would have to be from the star to receive the same insolation that Earth receives from the Sun.