National Aeronautics and Space Administration

Jump to Video: Keplers Search for Planets

Join NASA on the Kepler Mission as this traveling telescope images the light from faraway stars to locate Earth-sized and smaller planets. Using the transit method, the Kepler telescope measures the brightness of a star and uses the data to determine the sizes of planets orbiting the star, and their distance from the star.

The Kepler Mission is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine the fraction of the hundreds of billions of stars in our galaxy that might have such planets.

Are there planets orbiting other stars with characteristics similar to Earth? In recent years, scientists have discovered nearly 400 stars with orbiting giant planets. The challenge is to find terrestrial planets, those one-half to twice the size of the Earth, and especially those in the habitable zone of their stars where liquid water and possibly life might exist. We might soon find answers with Kepler – the first mission capable of detecting Earth-size and smaller planets in or near the habitable zone.

Recent Kepler surveys have identified over 1200 new 'exoplanets' and nearly 60 that are Earth-like in size and temperature.