One billion light years of nothing. That’s approximately 6 billion trillion miles of emptiness.
Can you approximate that? Okay, if the figure is too mind-numbing for you, just close your eyes … empty all thoughts … and do that until your last breathe!
That’s how vast it is! And we’re not talking about the size of the universe, just a tiny hole in it that has astronomers scratching their heads because they couldn’t see a thing in that hole.
The universe is supposed to be filled with stars, galaxies, black holes and dark matter. But in this part of the universe where a team of University of Minnesota astronomers cast their gaze on Thursday, there is totally nothing – not even dark matter or black holes.
Astronomers have known for many years that there are patches in the universe where nobody’s home. In fact, one such place is practically a neighbor, a mere 2 million light years away. But what the Minnesota team discovered, using two different types of astronomical observations, is a void that’s far bigger than scientists ever imagined.
“This is 1,000 times the volume of what we sort of expected to see in terms of a typical void,” said Minnesota astronomy professor Lawrence Rudnick, author of the paper that will be published in Astrophysical Journal. “It’s not clear that we have the right word yet … This is too much of a surprise.”
Rudnick was examining a sky survey from the National Radio Astronomy Observatory, which essentially takes radio pictures of a broad expanse of the universe. But one area of the universe had radio pictures indicating there was up to 45 percent less matter in that region, Rudnick said.
The rest of the matter in the radio pictures can be explained as stars and other cosmic structures between here and the void, which is about 5 to 10 billion light years away.
Rudnick then checked observations of cosmic microwave background radiation and found a cold spot. The only explanation, Rudnick said, is it’s empty of matter.
On the Net:
Rudnick paper: http://xxx.lanl.gov/pdf/0704.0908
National Radio Astronomy Observatory: http://www.nrao.edu/pr/2007/coldspot/