February 1, 2009
NASA Prepares Kepler For Launch
NASA on Friday showed off its new telescope aimed at determining if a habitable planet exists in other solar systems.
Set to launch aboard a United Launch Alliance Delta II rocket, the Kepler telescope is designed to survey more than 100,000 stars in the galaxy with the goal of identifying the number of sun-like stars that have Earth-size and larger planets, including those that lie in a star's "habitable zone," a region where liquid water, and perhaps life, could exist, the space agency said.Kepler is being prepared for launch on March 5 at Space Launch Complex 17 at Cape Canaveral Air Force Station.
Kepler will mark the first mission to survey the Milky Way galaxy in search of Earth-size planets around other stars.
"A null result is as important as finding planets," Michael Bicay, director of science at NASA's Ames Research Center in California, told reporters in Titusville, Florida.
Kepler has a 0.95-meter diameter photometer - or light meter - with a large field of view for an astronomical telescope. It is equipped with a 95 megapixel camera "“ the largest ever flown in space.
NASA hopes to determine the distribution of sizes and shapes of the orbits of larger planets in or near the habitable zone of wide variety planets.
"Kepler finds planets by looking for tiny dips in the brightness of a star when a planet crosses in front of it"”we say the planet transits the star," said NASA.
"Once detected, the planet's orbital size can be calculated from the period (how long it takes the planet to orbit once around the star) and the mass of the star using Kepler's Third Law of planetary motion."
"The size of the planet is found from the depth of the transit (how much the brightness of the star drops) and the size of the star. From the orbital size and the temperature of the star, the planet's characteristic temperature can be calculated. From this the question of whether or not the planet is habitable (not necessarily inhabited) can be answered," the space agency added.
To find a planet like Earth, scientists will need to catch at least four transits, a process that will take about 3 1/2 years. Its gaze will be fixed on a patch of sky between the constellations Cygnus and Lyra. Ground-based telescopes will be used to verify results, according to Reuters.
More than 330 planets have been observed circling stars in other solar systems, but none of them have had the size or properties suitable for sustaining life.
"There's several astrophysical phenomena that masquerade as planets," Bicay said. "We're going to have to sort them out."
Image Caption: Kepler Mission Star Field - An image by Carter Roberts of the Eastbay Astronomical Society in Oakland, CA, showing the Milky Way region of the sky where the Kepler spacecraft/photometer will be pointing. Each rectangle indicates the specific region of the sky covered by each CCD element of the Kepler photometer. There are a total of 42 CCD elements in pairs, each pair comprising a square. Credit: Carter Roberts / Eastbay Astronomical Society
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