Kepler's Precision Pointing

For four years, the Kepler spacescraft continuously and simulatenously observed and collected data on more than 150,000 stars. Its mission-- to determine if Earth-size planets orbiting in the habitable zone of stars like our sun are common or rare.

The stability of Kepler's pointing is measured in degrees, arcminutes, arcseconds and milli-arcseconds. To put that into perspective, the image compares the measurements using a movie theatre screen, a small bag of popcorn, a kernel of corn and a grain of salt.

During the four years of science operations, the pointing precision of the spacecraft was controlled to within a few milli-arcseconds. That is the equivalent of keeping your gaze steady on a grain of salt from a quarter mile away.

The next time you're asked to pass the salt think of the Kepler space telescope, and share its story.

Credit

NASA Ames/Wendy Stenzel

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