Lawrence Rudnick, together with Shea Brown and Liliya R. Williams, all from the University of Minnesota, have reported the find. The researchers came to their conclusion using data from the NRAO VLA Sky Survey (NVSS), which imaged the whole of the sky visible to the Very Large Array (VLA) radio telescope.
The empty region has been called the WMAP Cold Spot since it stood out like a sore thumb in the map of the Cosmic Background (CMB) radiation of the Wilkinson Microwave Anisotopy Probe (WMAP) satellite. It is some six to ten billion light years from Earth and a billion light years across. The nearest void to us is only 2 million light years away and it is thousands of times smaller.