By Ron Cowen
Holding his 3-month-old son, Joshua, in his arms, cosmologist David N. Spergel will proudly watch the launch next week of a NASA satellite that he helped father. The satellite will record the remnant glow from the infant universe in greater detail than ever before. Even before the Microwave Anisotropy Probe satellite gets off the ground, however, Spergel and his colleagues have hatched a plan to examine that early light in a dramatically different way.
The satellite will continue the practice of treating the cosmic microwave background (CMB) –the glow left over from the Big Bang–as a snapshot of the early universe. Taking a new perspective, Spergel and his colleagues propose to use that radiation as a flashlight to illuminate the evolution of structure in the universe over its 13-billion-year history. That evolution began with the condensation of gas clouds into fledgling galaxies and continued with production of the first stars and the assembly of galaxies into mammoth clusters.