Will Study More Than 100,000 Stars Over Next 3.5 Years

ANN REALTIME UPDATE 03.06.09 2252 EST: Liftoff! Moments ago, NASA's Kepler spacecraft lifted off the pad from Cape Canaveral Air Force Station in Florida, propelled towards the heavens atop a Delta II launch vehicle. T-Minus zero came at 1950 Pacific Time.

Sixty-two minutes after launch, Kepler is to separate entirely from its rocket and will be in its final Earth-trailing orbit around the sun, an orbit similar to that of NASA's Spitzer Space Telescope.

After a commissioning period lasting about two months, Kepler will begin its job of staring at more than 100,000 stars for three-and-one-half years, looking for planets. Its isolated perch behind Earth will give the telescope an unobstructed view of a single, very large patch of sky near the Cygnus and Lyra constellations.

"We will monitor a wide range of stars; from small cool ones, where planets must circle closely to stay warm, to stars bigger and hotter than the sun, where planets must stay well clear to avoid being roasted," said William Borucki, science principal investigator for the mission at NASA's Ames Research Center at Moffett Field, CA.

Borucki has been working on the mission for 17 years. "Everything about the mission is optimized to find Earth-size planets with the potential for life, to help us answer the question -- are Earths bountiful or is our planet unique?"

Original Report

0200 EST: NASA's Kepler mission to seek other Earth-like planets is undergoing final preparations for liftoff Friday, March 6, from Pad 17-B at Cape Canaveral Air Force Station in Florida. NASA has two opportunities for launch Friday, from 7:49 to 7:52 pm PST and 8:13 to 8:16 pm PST.

Kepler is designed to find the first Earth-size planets orbiting stars in habitable zones -- regions where water could pool on the surface of the planets. Liquid water is believed to be essential for the formation of life.

"This mission attempts to answer a question that is as old as time itself -- are other planets like ours out there?" said Ed Weiler, associate administrator for NASA's Science Mission Directorate at NASA Headquarters in Washington. "It's not just a science question -- it's a basic human question."

Kepler will find planets by looking for periodic dips in starlight. Planets that happen to pass directly in front of their stars from Earth's point of view cause the stars to dim by almost imperceptible amounts. Kepler's powerful camera, the largest ever flown in space, can see the faintest of these "winks."

Ahead of Kepler's launch, NASA provided the following "Fast Facts" about the upcoming mission:

• Kepler is the world's first mission with the ability to find true Earth analogs -- planets that orbit stars like our sun in the "habitable zone." The habitable zone is the region around a star where the temperature is just right for water -- an essential ingredient for life as we know it -- to pool on a planet's surface.
• By the end of Kepler's three-and-one-half-year mission, it will give us a good idea of how common or rare other Earths are in our Milky Way galaxy. This will be an important step in answering the age-old question: Are we alone?
• Kepler detects planets by looking for periodic dips in the brightness of stars. Some planets pass in front of their stars as seen from our point of view on Earth; when they do, they cause their stars to dim slightly, an event Kepler can see.
• Kepler has the largest camera ever launched into space, a 95-megapixel array of charge-coupled devices, or CCDs, like those in everyday digital cameras.
• Kepler's telescope is so powerful that, from its view up in space, it could detect one person in a small town turning off a porch light at night.

"We are very excited to see this magnificent spacecraft come to life when it reaches space," said James Fanson, Kepler project manager at NASA's Jet Propulsion Laboratory, Pasadena, CA.

ANN will provide updates on Friday's launch. Stay tuned.

FMI: www.nasa.gov/kepler