Astronomers see the Big Bang in action

Jason Corneveaux
Arizona State University

Recently, NASA astronomers announced new evidence supporting the Big Bang theory, which states that the universe was once subatomic in size and, in only one trillionth of a second, expanded to astronomical proportions. [1]

The findings are based on data collected by NASA’s Wilkinson Microwave Anisotropy Probe (WMAP) satellite. The satellite, which was launched in 2001, measures the Cosmic Microwave Background (CMB), or, more simply, the radiant heat left behind from the Big Bang. [1]

In 2003, researchers announced that, with WMAP data, they were able to capture a snapshot of the primordial universe and ascertained its age to be approximately 13.7 billion years old. Based on these preliminary findings, researchers determined that it was not until about 200 million years after the Big Bang that conditions cooled down enough to foster the development of the first stars. Another surprising twist came with the conclusion that the universe is comprised of approximately 4 percent ‘real’ matter and 23 percent dark matter, while the remaining 73 percent is composed of dark energy. The real mystery lies in the fact that dark matter and dark energy have yet to be understood and defined. [1]

According to Lyman Page, a WMAP researcher who spoke at the NASA press conference, “this new signal is roughly 100 times weaker than the signal we analyzed three years ago and about a billion times less than the radiant warmth we feel from the Sun.” [1]

Inflation theory, a sub-theory of the Big Bang, states that as the universe expanded following the Big Bang, some regions increased in size more quickly than others. Researchers were able to test this theory using the new WMAP observations, which revealed density fluctuations on the order of 1 to 10 billion light years. Such fluctuations are believed to have played a role in helping matter coalesce and form galaxies. [1]

These findings bring scientists closer to elucidating the origins of matter and the universe. The more we learn about the origins of the macrocosm, the more precise our answers will be to one of humankind’s most enduring questions.

References:

[1] Than, Ker. “Astronomers Detect First Split-Second of the Universe” Space.com. 16 March 2006. http://www.space.com/scienceastronomy/060316_wmap_results.html

Images courtesy NASA/WMAP Science Team