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Kepler mission graphic

Phase: Operating

Launch Date: March 06, 2009

Mission Project Home Page -

Program(s):Discovery, Exoplanet Exploration

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The Kepler Mission, a NASA Discovery mission, is specifically designed to survey our region of the Milky Way Galaxy to detect and characterize hundreds of Earth-size and smaller planets in or nearby the habitable zone. The habitable zone encompasses the distances from a start where liquid water can exist on a planet’s surface.

The scientific objective of the Kepler Mission is to explore the structure and diversity of planetary systems. This is achieved by surveying a large sample of stars to:

  1. Determine the percentage of terrestrial and larger planets that are in or near the habitable zone of a wide variety of stars
  2. Determine the distribution of sizes and shapes of the orbits of these planets
  3. Estimate how many planets there are in the multiple-star systems
  4. Determine the variety of orbit sizes and planet reflectivities, sizes, masses and densities of short-period giant planets
  5. Identify additional members of each discovered planetary system using other techniques
  6. Determine the properties of those starts that harbor planetary systems

Last updated: February 9, 2016

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