Thursday, April 26, 2007
New Exoplanet Discovery to Renew SETI Efforts?
In a follow-up to yesterday's post about the discovery of the most Earth-like exoplanet yet discovered, one of the co-discoverers hopes to be able to detect signs of life on this, and other exoplanets, within the next twenty years. Yahoo News AP wire excerpt:
GENEVA - Swiss scientist Michel Mayor, who heads the European team that announced the discovery of a new potentially habitable planet, has his sights set on an even bigger target, detecting signs of extraterrestrial life.
Mayor predicts that top researchers are less than two decades away from being able to detect real signs of such life — if it exists. "There's only one thing we can do. We can do science, we can do experiments. We have the methodology, the ability to do this simply on science, so let's do it," the University of Geneva scientist said Wednesday.
Mayor, who was credited in 1995 with co-finding the first planets outside our solar system, said the scientist in him was unsure of the presence of other life forms in our universe. "But, personally, I feel comfortable with the idea of life existing elsewhere," the 65-year-old said in a telephone interview with The Associated Press.
Leading astronomers are describing the discovery of the new planet as a big step in the search for life in the universe because it is just the right size, might have water in liquid form, and in galactic terms is relatively nearby at 120 trillion miles (20.5 light-years) away.
But there is still a lot that is unknown about the new planet, named 581 c, discovered by the European Southern Observatory's telescope in La Silla, Chile. The telescope, which Mayor helped design, has a special instrument that splits light to find wobbles in different wave lengths, revealing the possible existence of other worlds.
"It is an absolutely fantastic instrument with great precision," Mayor said, but added that the planet's diameter, atmospheric makeup and contents have yet to be confirmed.
Stephane Udry, the discovery team's lead author also based in Geneva, speculated that the new planet is probably full of liquid water, but conceded that he bases the conjecture on how planets form, not on any evidence.
Mayor said many more planets meeting scientists' requirements for habitability would be found, but that that the most significant short-term discovery would be that of a low-mass planet even more similar to Earth. 581 c is about five times heavier than our planet, but is still the smallest found exoplanet, or one that is outside our solar system.
Mayor predicted that NASA's Terrestrial Planet Finder and the European Space Agency's Darwin satellite would make increasingly significant contributions in the search for extraterrestrial intelligence. He said these institutions will be able to directly look for "signatures of life" on other planets, similar to the high presence of oxygen in our atmosphere, within 15 to 20 years.
As stated yesterday, this planet seems promising, but until we have more data, we really cannot speculate on the prospect that life exists there. Gliese 581c would be about 7 million miles from the host star, at such a close distance, this planet is probably tidally locked, like the Moon, keeping one face pointed to the star. This means that one half of the planet would be in constant sunlight, and the other in constant darkness. What this would do to weather patterns on the planet is anybodys guess -- especially since red dwarf stars are notorious for having significant flare activity. At that distance, flares from even a low-mass red dwarf would likely fry anything alive on the surface. At least Mr. Mayor and his team have their eyes on the prize, so to speak. I look forward to seeing more from this team, and others doing this exciting work.