Astronomers have discovered a planetary system comprising of three planets which are super earths (super earth is a planet which revolves around a star other than sun having mass higher than Earth but lower than Uranus and Neptune) revolving around the star named HD 7924 located approximately 55 light years away in the constellation Cassiopeia. This star is smaller, cooler, dimmer, and less massive than our Sun.

This discovery of planetary system around HD 7924 was made possible with the help of Automated Planet Finder (APF) at Lick Observatory and ground-based telescopes in Hawaii and Arizona. It is a fully robotic telescope searches for planets every clear night of the year, so planets and their orbits can be discovered and traced quickly.

Automated Planet Finder (APF)

  • This is the first telescope capable of detecting rocky planets that might support life in other solar systems. Extrasolar planetary research has been very successful at Lick Observatory.
  • Operates robotically on every clear night of the year, the APF is efficient in discovering extrasolar planets.
  • KEY FEATURES : Levy spectrometer has cutting-edge components and higher resolution
  • APF consists of a 2.4-meter automated telescope and enclosure, and the high-resolution Levy spectrograph


2009The Keck Observatory found the first evidence of planets orbiting HD 7924, discovering the innermost planet using the HIRES instrument installed on the 10-meter Keck I Telescope.
2015Two additional planets orbiting HD 7924 were later discovered by Keck Observatory after additional observations and the campaign by the APF Telescope.



Type              :             SUPER EARTH

Mass             :             7 to 8 times that of Earth and

Time               :            complete their orbit’s in just 5, 15, 24 days around HD 7924.