Giant hole discovered in the universe

Researchers discover giant hole in the universe

Astronomers have found a giant hole in the universe for which they have no explanation. There is not a single star in the region, which is nearly a billion light-years across. And even black holes or dark matter are not to be found there.

It is an inconceivably large nothingness that astronomers have now discovered. The gigantic gap in the universe, which researchers at the University of Minnesota have discovered, is almost a billion light-years wide.

In the cosmic void there is absolutely nothing, Lawrence Rudnick and his colleagues believe: no stars, no galaxies, no black holes, even for the mysterious dark matter there is no evidence. Neither previous research nor computer simulations provided an explanation for the phenomenon, the astronomers report in the Astrophysical Journal. The void lies in the constellation Eridanus.

The universe consists of only about four percent conventional matter such as atoms, dark matter and dark energy together make up about 96 percent of the mass. Barren regions in space where absolutely nothing can be found have been known for some time. But the hole that has now been discovered is beyond the imagination of researchers and puts them in a bind to explain it.

"It's a thousand times bigger than a typical void," Rudnick explains. They don't have a suitable name for it yet, he adds. "This is a huge surprise."

Losers in cosmic wrestling

Astronomers had discovered the void using the Very Large Array (VLA) radio telescopes. The facility is located in the U.S. state of New Mexico. They then compared the measurements with observations of cosmic background radiation - made with Nasa's Wilkinson Microwave Anisotropy Probe (WMAP) satellite. These confirmed that there is a giant cold spot in the universe. The only explanation is that there is no matter there, Rudnick said. The area is between five and 10 billion light-years from Earth.

James Condon of the National Radio Astronomy Observatory said it could also be a statistical freak of nature. But he said it is more likely that it is actually a giant hole.

"This is probably something that needs to be taken very seriously," commented University of Hawaii astronomer Brent Tully, who, like Condon, was not involved in Rudnick's work. Tully had been studying another void that is much smaller and only about two million light-years from Earth. Holes in the universe are probably created by areas with a large mass using their gravity to pull matter from less dense areas, Tully explained. After 13 billion years, these holes are something of losers in the battle with regions where there are particularly high concentrations of matter, he added.




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A giant hole in the Universe is devoid of galaxies, stars and even lacks dark matter, astronomers said on Thursday.

The team at the University of Minnesota said the void is nearly a billion light-years across and they have no idea why it is there.

"Not only has no one ever found a void this big, but we never even expected to find one this size," said astronomy professor Lawrence Rudnick.

Writing in the Astrophysical Journal, Rudnick and colleagues Shea Brown and Liliya Williams said they were examining a cold spot using the Wilkinson Microwave Anisotropy Probe satellite, and found the giant hole.

"We already knew there was something different about this spot in the sky," Rudnick said. The region stood out as being colder in a survey of the Cosmic Microwave Background -- the faint radio buzz left over from the Big Bang that gave birth to the Universe.

"What we've found is not normal, based on either observational studies or on computer simulations of the large-scale evolution of the Universe," Williams said in a statement.

The astronomers said the region even appeared to lack dark matter, which cannot be seen directly but is usually detected by measuring gravitational forces.

The void is in a region of sky in the constellation Eridanus, southwest of Orion.

The researchers have posted images on the Internet at

http://www.nrao.edu/pr/2007/coldspot/graphics.shtml