Earthlike Planet Orbiting Nearby Star

The Bad Astronomer writes "Astronomers in Europe have announced the discovery of a planet with only 5 times the Earth's mass, orbiting a red dwarf star 20 light years away. It orbits the star so closely that it only takes 13 days to go around... but the star is so cool that the temperature of the planet is between 0 and 40 Celsius. At this temperature there could be liquid water. Models indicate the planet is either rocky like the Earth or covered in an ocean. While it's not known if there actually is liquid water on the planet, this is a really big discovery, and indicates that we are getting ever closer to finding another Earth orbiting an alien star."

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[Beolach]

The BBC and Scientific American have good quotes from Stephane Udry of the Geneva Observatory, lead author of the scientific paper reporting the results. Others are already calling it "possibly habitable".

Very cool news!

quick maths on gravity

[quenda]

Assuming its the same density as Earth, cube root of 5 is 1.7, so 1.7x the radius. Gravity is mass/r^2, 5/1.7^2 x earth, so 1.7 or 70% more. ie surface gravity only goes up with the cube root of mass, for a constant density, so 5x isn't as bad as it sounds. But if it has more rock, and less iron core, the surface might me much nicer.

Re:How long to get there?

[Wonko the Sane]

Don't think so. If that were the case, it could be 2,000,000,000 light years, and it would still be instantaneous. It doesn't make any sense. Of course, neither does the ability to travel at light-speed.

As you approach the speed of light, your perception of time changes with respect to a stationary observer. If you could actually achieve the speed of light (you can't) the transit time would be 0, no matter how much distance you had traveled.

Re:Uninhabital new worlds

[Filip22012005]

From Pubmed:

ORL J Otorhinolaryngol Relat Spec. 1995 Jul-Aug;57(4):189-93.
Effect of prolonged hypergravity on the vestibular system: a behavioural study.Sondag HN, de Jong HA, Oosterveld WJ.
Vestibular Department ENT, University of Amsterdam, The Netherlands.

Golden hamsters were exposed to conditions of 2.5 times normal gravity (hypergravity, HG) for 4 months. During this period, tests were carried out to study equilibrium maintenance, swimming behaviour and open-field behaviour of these HG hamsters and of control hamsters living in a normal-gravity environment. The tests proved to be useful devices for detecting differences in perceptive-motor behaviour between HG hamsters and control hamsters. The HG hamsters had more difficulties in balancing on tubes and orientation during swimming. In the open-field study, the HG hamsters showed less locomotor activity than control hamsters. However, no differences were observed between the groups in washing, rearing and number of times having defaecation. These findings indicate that the daily transition from 2.5 to 1 g was not experienced as stressful by the hamsters, although performance on several perceptive-motor tasks was decreased, especially during the first weeks.