Physics Today: Eight new papers interpreting new data from the WMAP (Wilkinson Microwave Anisotropy Probe) mission have been released. WMAP is designed to elucidate the history and composition of the universe by creating an high resolution map of temperature fluctuations and polarization in the cosmic microwave background radiation.

The new papers are based on five-years worth of observations, two years more than the 2003 set of papers (see Physics Today April 2003, page 21). The new data have yielded improved determinations of the Hubble constant (70.1 ± 1.3 km/s per Mpc) and the cosmic density of baryonic (ordinary) matter (4.6 ± 0.2% pf the total cosmic budget of matter and energy) that has implications for cosmological models of the early universe. WMAP has also refined the age of the Universe to 13.73 ± 0.12 billion years. The new WMAP data rules out the existence of very massive neutrino species.

Related Links
Physics Today April 2003, page 21
WMAP group
The Reference Frame