WASHINGTON, March 16 (Xinhuanet) -- Scientists said Thursday that with the aid of NASA's WMAP spacecraft, they have found evidence that the universe went through a rapid expansion in less than a trillionth of a second after the Big Bang, which is believed to give birth to the universe.

    From what they called "the most precise measurements of our infant universe" by the WMAP (Wilkinson Microwave Anisotropy Probe), scientists have found "new evidence that the universe suddenly grew from sub-microscopic to astronomical size in less than the blink of an eye," said physicist Charles Bennett of Johns Hopkins University, principal investigator for the WMAP spacecraft.

    "This tremendous inflation of the universe happened in much less than a trillionth of a second," he said at a telephone news conference.

    The evidence came from the analysis of brightness variations in the cosmic microwave background. The WMAP detected light that was produced in the early universe and seen in the form of faint microwaves. This early light helped scientists perceive tiny variations in the infant universe, where nothing but tiny differences in temperature existed.

    Scientists said these tiny temperature differences formed patterns that eventually clumped into stars, galaxies and planets.

    The WMAP's latest observations confirmed WMAP scientists' estimate three years ago of the age of the universe, at about 13.7 billion years, but revised the time they reported of stars beginning to shine to 400 million years after the Big Bang from 200 million years.

    The discoveries are scheduled to be published in a future issue of the Astrophysical Journal.

    The WMAP was launched by NASA in 2001, and it is expected to work through September 2009. The probe is now about 1.6 million km away from the Earth. Enditem