Washington, March 7: NASA's Kepler mission, which would search other Earth-like planets, has been successfully launched into space from Cape Canaveral Air Force Station, Florida, US, aboard a United Launch Alliance Delta II.
Kepler is designed to find the first Earth-size planets orbiting stars at distances where water could pool on the planet's surface. Liquid water is believed to be essential for the formation of life.
Engineers acquired a signal from Kepler at 12:11 a.m. on March 7th, after it separated from its spent third-stage rocket and entered its final sun-centered orbit, trailing 950 miles behind Earth.
The spacecraft is generating its own power from its solar panels.
Engineers have begun to check Kepler to ensure it is working properly, a process called 'commissioning' that will take about 60 days.
In about a month or less, NASA will send up commands for Kepler to eject its dust cover and make its first measurements.
After another month of calibrating Kepler's single instrument, a wide-field charge-couple device camera, the telescope will begin to search for planets.
The first planets to roll out on the Kepler 'assembly line' are expected to be the portly 'hot Jupiters' - gas giants that circle close and fast around their stars.
Neptune-size planets will most likely be found next, followed by rocky ones as small as Earth.