The emptiness of space is really empty in constellation Eridanus

William Atkins
Saturday, 25 August 2007 21:33

Science - Space

A giant hole in the universe was found by University of Minnesota astronomers using the NASA Wilkinson Microwave Anisotropy Probe (WMAP) satellite.       

The hole is about one billion light-years across, is largely devoid of any matter, and is very puzzling to astronomers. Smaller holes are well known to exist throughout the universe. Such a gigantic hole in space is seen as a very rare occurrence in the universe.

One of the researchers, Lawrence Rudnick, Department of Astronomy professor at the University of Minnesota, says of the discovery, “Not only has no one ever found a void this big, but we never even expected to find one this size.”

Rudnick added, "What we've found is not normal, based on either observational studies or on computer simulations of the large-scale evolution of the Universe.” [Reuters, UK]

The finding of Rudnick, Shea Brown, and Liliya R. Williams is found in the August 3, 2007 issue of the Astrophysical Journal as the article “Extragalactic Radio Sources and the WMAP Cold spot”.

The astronomers were using the WMAP probe to survey the cosmic microwave background (CMB) radiation, the electromagnetic radiation—which peaks at a frequency of about 160.2 gigahertz—that encompasses the universe and is thought to be the left-over radiation from the big bang explosion that created the universe.

The mission of WMAP is to measure the temperature of the radiant heat that remains from the big bang. The satellite was launched by NASA on June 30, 2001. Since that time, it has been mapping out the CMB radiation in order to help scientists learn more about the structure, evolution, and eventual fate of the universe.

When the Minnesota astronomers looked at one section of the sky, within the southern hemisphere constellation Eridanus, they found a region of space that was colder than the other regions of space.

An image of the void in space is found at the website “Graphics: Astronomers Find Enormous Hole in the Universe”, as part of the National Radio Astronomy Observatory article “Astronomers Find Enormous Hole in the Universe”.

The researchers said of their discovery within their Astrophysical Journal paper: “The detection of an extreme “cold spot” … in the foreground-corrected WMAP images was an exciting but unexpected finding.”