More on finding extrasolar Earths
Saturday, June 21, 2008
Two days ago there was an article on space.com with a general overview of how the hunt for extrasolar Earths (the only thing that will completely change the average person's view of space in my opinion) here.
There's nothing there that I haven't touched on here before but it's still a good overview of how things are going. Here's part of it (dealing with the Kepler Mission, one of the most exciting missions this decade):
Super-Earths are beginning to be found with high-precision instruments like HARPS. Hints of small planets have also been reported by the COROT (COnvection ROtation and planetary Transits) Mission and by the gravitational lensing experiments underway.
But the holy grail — an Earth-size planet in the habitable zone of its star — awaits NASA's Kepler Mission.
The Kepler spacecraft launches in February 2009, 400 years after Johannes Kepler published his first two laws of planetary motion in Astronomia Nova, the "New Astronomy," which first described planets orbiting on ellipses and at varying speeds around the sun. Ten years later, he published his third law, which relates the period of the planet to its mean distance from the sun. Kepler used his discoveries to predict solar transits of Mercury and Venus, but did not survive to observe them.
Soon, NASA scientists will seek transits to discover Earth-size planets about distant stars. And, they named the mission in honor of Johannes Kepler.
The Kepler Mission is especially designed to discover small planets around sun-like stars by observing transits. The Kepler Mission will observe more than 100,000 stars for at least 3.5 years, seeking evidence of other Earths. Lots of hot, close-in planets will be discovered in the first months of the mission.
Finding Earth-size planets in Earth-like orbits requires patience, because observations must be repeated to confirm discoveries. If an alien astronomer in a distant solar system were looking for us, Earthly transits would be seen once per year, and that good astronomer would require at least three transit observations to announce a discovery. The same is true for the Kepler scientists. Kepler's scientific prospectors should be announcing discoveries of Earth-size planets in habitable zones by 2011-2012.
So there it is: 2011-2012, if not earlier. That's when space will cease to look like a large uninhabitable black ocean, and begin to look like a large uninhabitable black ocean - with huge inhabitable islands here and there to visit if we can just get to them.
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