Bruce Peterson (astronomer)

Prior to obtaining his PhD, Peterson and James Gunn argued in 1965 that if the universe had a high enough density of neutral hydrogen atoms near a quasar, then almost all photons emitted by the quasar that are more energetic than the Lyman-alpha wavelength of 1216 angstroms should be absorbed by the neutral hydrogen. The effect, called the Gunn–Peterson trough,^[2] should yield zero emission at wavelengths shorter than 1216 angstroms (after shifting for redshift) in the observed spectrum of the quasar.^[3] The effect was detected in 2001 in a quasar at a redshift of 6.28.^[5]

Peterson obtained a research position at Mount Stromlo Observatory at the Australian National University in Australia, where he continued research into quasars and the Stromlo-APM redshift survey.^[1] He played a major role in the MACHO Project that was conducted on a Mount Stromlo telescope to look for massive compact halo objects, a possible candidate for dark matter.^[6] Peterson was active in the 2dF Galaxy Redshift Survey, in identifications of gamma-ray bursts and in searches for high-redshift quasars.^[2]

In 2004, Peterson received a Thomson ISI Citation Laureate for his "outstanding contribution to Space Sciences in Australia". He had the highest number of citations among Australian astronomers for the period from 1980 to 2004: 176 papers cited 11039 times, according to Thomson ISI.^[2]