What is the current accepted density of the universe according to the 5-year data reports from the WMAP?

Question

Has the 5-year report from the WMAP satellite changed the value for the density of the universe since the 3-year report (omega = 1.02 +or- 0.02) Please cite your credible sources.

Answer 1

duh

Answer 2

The papers submitted to the Astrophysical Journal describing and analyzing the five-year results can be found at the LAMBDA website.  The relevant paper is the one by Komatsu et al. "Five-Year Wilkinson Microwave Anisotropy Probe Observations: Cosmological Interpretation"

Omega[k] is not well-constrained by the WMAP data alone.  Combining the data with observations on Type 1a supernovae (SN) and baryon acoustic oscillations (BAO), which come from measurements of the distribution of galaxies in data sets such as the Sloan Digital Sky Survey (SDSS) and the 2-degree-field Galaxy Red-shift Survey (2dFGRS), produces a result with much tighter constraints.

The headline figure is -0.0179 < Omega[k] < 0.0081 which reduces to -0.0178 < Omega[k] < 0.0066 when the equation of state of dark energy, w, is constrained to a value of -1.  The figures are 95% confidence limits.

Answer 3

the best way I've ever heard that phrased involves waling into a vast cathedral with 3 grains of sand--and then the cathedral would be more densely packed with sand than the universe is with stars.

Answer 4

Current estimate is 2.11^ minus 29 kg/cubic meter