Gliese 581D
by Heather Catchpole
‘Gliese 581d’ is a super-Earth about eight times heavier than our own planet. Gliese 581d and its three known sister planets orbit the low-mass red dwarf star Gliese 581, about 20.3 light-years (194 trillion km) away from us, in the constellation Libra.
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| European Southern Observatory |
| Gliese 581d is the outlying planet in the Gliese 581 system, and orbits its parent star every 66.8 days. It may be covered by a large and deep ocean and is the first serious ‘waterworld’ candidate discovered beyond our Solar System. |
Imagine life from the surface of this planet – its sun, being one third the size of our Sun and 50 times fainter – would be a dull, red glow in the sky. Under a deep, possibly planet-encompassing ocean, thick layers of ice surround the planet’s rocky centre.
It’s the “first serious waterworld candidate”, according to astronomer and exoplanet hunter Stephane Udry, from the Geneva Observatory in Switzerland, who was part of the team that discovered the planet in April 2007. More..
