APF and Keck Observatory discovers three Super-Earths around a nearby Star

Scientists have recently discovered three planets, categorized as super-Earths due to their massive size, orbiting a nearby star; the process of discovery involves the use of a robotic telescope.

Each of these newly discovered planets is seven to eight times bigger than the earth. The star they are orbiting, on the other hand, is located 54 light-years away from the Earth; this distance makes the star a close neighbor of our planet.

The distance between these three newly discovered planets and the star they are orbiting is less than the distance between the Sun and Mercury. They complete their orbiting respectively in just 24, 15 and five days.

The team of researchers managed to discover these new planets by spotting the star’s wobble caused by the gravitational pull of the orbiting planets. Here, it must be mentioned that the name given to the star in question is HD 7924.


The robotic telescope used for discovering these super-Earths is called APF or Automated Planet Finder Telescope. The telescope that is located in the W M Keck Observatory in Maunakea, Hawaii and Lick Observatory in California succeeded in tracing the orbits of the three massive planets out using Doppler technique. In the past, this technique has successfully located hundreds of planets, the majority of which are large in size, orbiting neighboring stars.

The APT or Automatic Photometric Telescope installed in Arizona’s Fairborn Observatory, on the other hand, was used for making crucial measurements, for instance, HD 7924’s brightness. This was important for assuring the validity of the discovery.


BJ Fulton of the University of Hawaii said that initially the research team used APF in the same manner as they would have used an ordinary telescope. However, later they decided to use software that will replace them with a robot.

The first evidence of existence of planets orbiting the HD 7924 was found way back in 2009; the entity that made that discovery possible was the Keck Observatory. The event involved discovery of the innermost planet using an instrument called the HIRES; HIRES was installed on the 10 m long Keck I telescope. The other two planets took another six years to be discovered.

Researchers are saying that these three super-Earths do not resemble any entity of our solar system.