Welcome to The Sound of Science from WNIJ and NIU STEAM. It’s a weekly series explaining important STEM concepts. Today’s hosts are Jeremy Benson and Newt Likier.
We have a question here from Sky, who asks “Why did the Big Bang happen?”
Well, Sky, the short answer is we really don’t know!
That was easy. Next question?
Not so fast, Newt. We don’t know why it happened, yet, but scientists are working on getting a better understanding of how it happened. We can’t go back in time and observe the big bang itself, but we can study it using something called the cosmic microwave background radiation. The cosmic microwave background, or CMB, is the faint bit of radiation that’s still left from the intense moment when the universe exploded into expansion.
The coolest thing about the CMB, pun intended, is its temperature. On average, it’s about negative 270 degrees Celsius. Or 2.72548 degrees above absolute zero if we’re being precise. And precision is exactly what these scientists are after. The warmest and coolest parts of the CMB only vary by about a thousandth of a degree.
Thanks to experiments like NASA’s Cosmic Background Explorer and Wilkinson Microwave Anisotropy Probe, we are building a very precise map of that background radiation across the entire sky. These maps are like baby pictures showing how energy was distributed across space in the first moments of the exploding universe.
By studying these baby pictures and analyzing those minute variations in temperature, scientists have found evidence of a universe created by a rapid expansion of hot gas. New experiments studying the polarization of the CMB radiation may help us to understand more about the role dark matter played in the formation and expansion of our early universe.
So, we may not know why the Big Bang happened. But we are always learning more about our expanding universe. And as our tools get better and better, who knows what we’ll discover tomorrow.
This has been the Sound of Science on WNIJ. Where you learn something new every day.
