WASHINGTON - NASA is preparing to launch the Kepler space telescope Friday on the space agency's first mission to detect Earth-like planets that may harbor life in our solar system.
Kepler's massive telescope is scheduled for launch atop a Delta II rocket from Cape Canaveral Air Force Station, in Florida, on March 6 at 10:48 pm (0348 GMT Saturday).
It will be the National Aeronautics and Space Administration's first mission in search of Earth-like planets orbiting suns similar to ours, at just the right distance and temperature for life-sustaining water to exist.
"Kepler is a critical component in NASA's broader efforts to ultimately find and study planets where Earth-like conditions may be present," Jon Morse, astrophysics division director at the US space agency's Washington headquarters, told a press conference last month.
"The planetary census Kepler takes will be very important for understanding the frequency of Earth-size planets in our galaxy and planning future missions that directly detect and characterize such worlds around nearby stars," he added.
Kepler's discoveries "may fundamentally alter humanity's view of itself."
Equipped with the largest camera ever launched into space -- a 95-megapixel array of charged couple devices, known as CCDs -- the Kepler telescope is able to detect the faint, periodic dimming of stars that planets cause as they pass by.
"If Kepler were to look down at a small town on Earth at night from space, it would be able to detect the dimming of a porch light as somebody passed in front," according to Kepler project manager James Fanson.
At a cost of close to 600 million dollars, the Kepler mission will last three years and examine more than 100,000 sun-like stars around the Swan and Lyre constellations of the Milky Way.
Astrophysicist Alan Boss is convinced that either Kepler or the French-led COROT satellite that has been in orbit since 2006 will be able to find Earth-sized planets over the next few years.
"I will be absolutely astonished if Kepler or COROT didn't find any earth-like planets, because basically we are finding them already," Boss told reporters at a February science conference in Chicago.
COROT has already discovered the smallest extraterrestrial planet so far. At a little over twice the Earth's diameter, the planet is very close to its star and very hot, astronomers reported earlier this month.
William Borucki, Kepler's principal investigator based at NASA's Ames Research Center in California, said the project was about finding places where conditions are perfect for sustaining life.
"What we're interested in finding are planets that are not too hot and not to cold," he said.
"We're looking for planets where the temperature is just about right for liquid water on the surface of the planet."
"If we find that many, it certainly will mean that life may well be common throughout our galaxy, that there is an opportunity for life to have a place to evolve," noted Borucki.
"If none or only a few of these planets are found, it might suggest that habitable planets like Earth are very rare and Earth may be a lonely outpost for life," he said.
Astronomer Debra Fischer at San Francisco State University said that NASA's mission is a cornerstone in understanding what types of planets are formed around other stars.
Information that Kepler will help to compile, she said, "will help us chart a course toward one day imaging a pale blue dot like our planet, orbiting another star in our galaxy."