NASA telescope reveals largest batch of Earth-size, habitable zone planets around a single star

22 February 2017

UCLan researcher included in international research team

"By precisely monitoring the brightness of the host star, we have been able to detect the planets as they pass in front of the star and block a small amount of light."

Dr Daniel Holdsworth, a postdoctoral research associate at the University of Central Lancashire’s (UCLan) Jeremiah Horrocks Institute for Mathematics, Physics and Astronomy, is one of the European scientists involved in the project and monitored the TRAPPIST-1 system in an attempt to measure the transit of the outer most planet in the system.

He said: “The TRAPPIST-1 planetary system hosts the largest number of exoplanets close enough to their parent star that liquid water might exist. By precisely monitoring the brightness of the host star, we have been able to detect the planets as they pass in front of the star and block a small amount of light. By knowing how big the star is, and how much light is blocked, we can calculate how big the planets are. The planets are small and rocky and are comparable in size to the Earth. At just 40 light years away, this makes TRAPPIST-1 a prime target to study the atmospheres of exoplanets to search for traces of water, and even life, in this nearby solar system.

“As the TRAPPIST-1 star is very cool, just 2,550 degrees (compared to the Sun at 6,000 degrees) the team used NASA’s Spitzer space telescope, which is very sensitive to red light, to monitor the star for 500 hours. These data, in conjunction with data collected at some of the largest telescopes around the world, lead to this fantastic discovery.”