Scientists at the Max Planck Institute for Astrophysics in Germany say they've found the origin of galactic background emissions -- white dwarf stars.

The origin of the so-called galactic X-ray background has been a long-standing mystery. But the Max Planck scientists say they've discovered the blanket of X-ray light is not diffuse, as many have thought, but emanates from hundreds of millions of individual sources that are dominated by a type of dead star called a white dwarf.

If confirmed, the finding would have a profound impact on understanding of the history of the galaxy, from star formation and supernova rates to stellar evolution. The results also will solve major theoretical problems, yet point to a surprising undercounting of stellar objects, the scientists said.

The discovery is discussed by the Max Planck researchers and by scientists from the Space Research Institute of the Russian Academy of Sciences in Moscow in two papers published in the journal Astronomy & Astrophysics.

Copyright 2006 by United Press International