August 10, 2001

New View of Primordial Helium Traces Structure of Early Universe

NASA's Far Ultraviolet Spectroscopic Explorer (FUSE) satellite has given astronomers their best glimpse yet at the ghostly cobweb of helium gas left over from the Big Bang, which underlies the universe's structure. The helium is not found in galaxies or stars but spread thinly through the vastness of space.

The observations, published in the August 10 issue of the journal Science, help confirm theoretical models of how matter in the expanding universe condensed into a web-like structure pervading all the space between galaxies. The helium traces the architecture of the universe back to very early times. This structure arose from small gravitational instabilities seeded in the chaos just after the Big Bang.

"Visible galaxies are only the peaks in the structure of the early universe. The FUSE observations of ionized helium show us the details of the hills and valleys between the mountain tops," said Gerard Kriss, leader of the FUSE observing team and astronomer at the Space Telescope Science Institute in Baltimore.

For the complete press release, go to: http://www.gsfc.nasa.gov/topstory
/20010809fuse.html