Artist's conception of the newly discovered planet orbiting a brown dwarf "star"
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NASA's Exoplanet Exploration Program
Small Planet, Small Star
News story originally written on June 2, 2008
It isnít easy to find a planet that is like Earth. Most of the planets that astronomers are finding outside of our solar system are huge - much more massive than Earth.
However, astronomers searching the Universe have found a small planet thatís a lot like Earth. Itís 3000 light years away and itís the smallest planet ever found that is orbiting a normal star - only three times more massive than Earth.
The star that it orbits is not large. It is perhaps one-twentieth the mass of our Sun. Finding the small planet orbiting the small star suggests that small stars may be good places to look for other small planets.
The small star might be massive enough to have nuclear reactions in its core, making it a lot like our Sun. But it may be too small for nuclear reactions. If so, then it is called a brown dwarf.
The first measurements of the new planet and its star were made by astronomers in New Zealand. Scientists in Chile made observations too. Then scientists around the world examined the data.
If there are other planets in the Universe that are like Earth, they might be places where life could survive.
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