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Keck Interferometer (KI)

Keck Interferometer (KI) mission graphic

Phase: Operating

Mission Project Home Page -

Program(s):Exoplanet Exploration

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The Keck Interferometer is a ground-based component of NASA's Exoplanet Exploration Program. At 4,150 meters (13,600 feet) above the Pacific Ocean, atop the dormant volcano Mauna Kea on the "Big Island" of Hawaii, the twin Keck Telescopes are the world's largest telescopes for optical and near-infrared astronomy. The Keck Interferometer joins these giant telescopes to form a powerful astronomical instrument.

The basic concept for the Keck Interferometer was described in the TOPS (Toward Other Planetary Systems) report and restated in the 1996 Road Map for the Exploration of Neighboring Planetary Systems, reviewed by a blue ribbon panel chaired by Professor Charles Townes, a Nobel Prize winning physicist. In 1996, in response to the recommendations of these and other advisory committees, NASA embarked on a program to implement the Keck Interferometer project. NASA selected JPL to implement the interferometer jointly with the California Association for Research in Astronomy (CARA). In 1996, NASA also joined as a partner in the Keck Observatory.

Since 2003, the Keck Interferometer has been in scheduled operation for a range of peer-reviewed science programs. For example, KI observations have been used to study questions about the origins of stars and galaxies. Recent results include observations of disks around young stars which may be in the process of forming planets, and measurements of the massive disks of gas and dust surrounding the black holes at the center of several nearby galaxies.

In 2008 and 2009, the Keck Interferometer Nuller conducted operations for a group of key projects to study emissions from faint dust clouds around other stars. These dust clouds reflect light and give off heat, and so interfere with the search for planets. The KI observations are several times more sensitive than previous searches. Most nearby stars searched by KI had no detected dust clouds, and thus they remain as viable candidates for future searches for terrestrial planets.

Ongoing improvements to KI, funded by a grant from the National Science Foundation to the Keck Observatory, will build on the existing infrastructure to add the capability to observe much fainter targets, and to add an astrometry mode which will measure the true mass of exoplanets and test the effects of general relativity at the center of our own galaxy.

Related Links
  • Virtual Tour of the KI -
  • Animation of the KI -