ESOcast 83 Ultracool Dwarf Planets

The search for signs of life — planets around ultracool dwarfs

2 May 2016

Where is the best place to look for signs of life in the Universe? New findings by an international team of astronomers suggest we should be looking at nearby stars known as ultracool dwarf stars. These are very dim stars, much cooler and redder than the Sun, and not much larger than Jupiter. But they are quite common, accounting for around 15% of the stars near to the Sun.

2MASS J23062928-0502285, also known as TRAPPIST-1, is an ultracool dwarf in the constellation of Aquarius. It is only 40 light-years from Earth, so despite its being very dim, astronomers were able to make very precise measurements using a specialist telescope called TRAPPIST at ESO’s La Silla Observatory in Chile.

In this ESOcast, you will hear how they discovered three Earth-sized planets in orbit around TRAPPIST-1, which may have regions on them that could sustain life. These are the first such planets to be found around an ultra cool dwarf star and they are the best target for future telescopes to search for the signs of life elsewhere in the Universe.

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Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591

About the Announcement



Artist’s impression of the ultracool dwarf star TRAPPIST-1 and its three planets
Artist’s impression of the ultracool dwarf star TRAPPIST-1 and its three planets


ESOcast 83: Ultracool Dwarf with Planets
ESOcast 83: Ultracool Dwarf with Planets