Recent 'Earth-like planet' found in April 'too hot' for life say some scientists

Tuesday, June 12, 2007

Artist's impression of the planetary system around the red dwarf Gliese 581.
Image: European Southern Observatory.

German and American scientists have announced that the recent planet, Gliese 581c is too hot to host any life that would be found on Earth. It orbits around the star Gliese 581.

"It’s just too hot. I would not recommend mankind to move to that planet right now," said Potsdam Institute for Climate Impact Research astronomer who was part of the study, Dr. Manfred Cuntz who also said that the same system that Gliese 581c is in may have another planet that could be comfortable for humans.

The planet, Gliese 581d orbits the same star as Gliese 581c but at a distance of 23 million miles. The researchers say that the planet could have a "greenhouse" effect and that water that may be present on the planet would be liquid. If no greenhouse effect is present, the planet would have frozen water.

"We cannot cool down an atmosphere of a planet, but we can heat it up. Despite the adverse conditions of this planet, at least some primitive forms of life may be able to exist on its surface," added Cuntz. File:Gliese 581 c in the habitable zone.svg

A range of theoretical habitable zones with stars of different mass (our solar system is at the centre, a red dwarf similar to Gliese 581 at the bottom).
(Image missing from Commons: image; log)

Some scientists disagree and say that Gliese 581 is very old and that its light is dimmer than that of a newer star.

Scientists began to monitor Gliese 581c right after the announcement of its discovery in April for six weeks using the Microvariability and Oscillations of STars (MOST), operated by the Canadian Space Agency.

"Gliese 581 seems remarkably stable over the six weeks it was monitored by MOST. The brightness of the star changed by only a few tenths of a percent over that time. This level of stability means that it provides a stable source of light -- hence heat -- to the surface of planet Gliese 581c. The climate there should not be a wild rollercoaster ride that would make it difficult for life to get a foothold," said astronomer at the University of British Columbia, Jaymie Matthews.

Matthews says that Gliese 581 is much older than the Sun and Earth and that life should have already evolved on the surface.

"So if Gliese 581 has been around for at least that long, it’s more encouraging for the prospects of complex life on any planet around it," added Matthews.