Wilkinson Microwave Anisotropy Probe DR4
The data made available through this page has been updated. The most recent version of this data may be accessed through https://lambda.gsfc.nasa.gov/product/wmap/current/"
The WMAP (Wilkinson Microwave Anisotropy Probe) mission is designed to determine the geometry, content, and evolution of the universe via a 13 arcminute FWHM resolution full sky map of the temperature anisotropy of the cosmic microwave background radiation. The choice of orbit, sky-scanning strategy and instrument/spacecraft design were driven by the goals of uncorrelated pixel noise, minimal systematic errors, multifrequency observations, and accurate calibration. The skymap data products derived from the WMAP observations have 45 times the sensitivity and 33 times the angular resolution of the COBE DMR mission. The WMAP mission characteristics are summarized in the table below.
In the first release of WMAP data (February 2003), only the temperature data and analyses from the first year of operations at L2 were provided.
Much more information and data was provided in the second release (March 2006); the differences between the two are characterized by:
The third data release took place in March 2008. It was characterized by:
The fourth release of data is now available. It is characterized by:
The WMAP satellite ended science observations on 20 August 2010. On 8 September 2010, WMAP departed L2 for a heliocentric orbit approximately 7% larger the Earth's orbit. The complete nine-year data set is now being processed and the final legacy data products will be released by 2012.