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Yale Astronomy

Lick Planet Search

The Lick Observatory Planet Search (LPS) is the longest running exoplanet survey in the world. The Hamilton Spectrograph is used with either the 3-meter Shane Telescope or the 0.6-meter Coude Auxiliary Telescope (affectionately known as "The CAT") to measure the change in a star's radial velocity over time.

Some noteworthy discoveries credited to the Lick Observatory Planet Search include:

  • confirmation of the first planet found to orbit a sun-like star (51 Peg b),
  • the first multi-planet system (Ups And b, c, d), and
  • the first five-planet system (55 Cnc b, c, d, e, f).

Additionally, major LPS contributions to the field include:

  • the detection of planets around evolved stars,
  • a catalog of over 2,600 stellar chromospheric activity measurements, and
  • the planet-metallicity correlation.

The 25 year project is summarized in a paper by Fischer, Marcy & Spronck 2014, "The Twenty Five Year Lick Planet Search"
ApJS, 210, 5