" Wilkinson Microwave Anisotropy Probe, WMAP, is a NASA Explorer mission measuring the temperature of the cosmic background radiation over the full sky with unprecedented accuracy. This map of remnant heat from the Big Bang provides answers to fundamental questions about the origin and fate of our universe. " — From the NASA/WAMP website The probe is over 930,000 miles from Earth and effectively scans the entire sky every six months.
Temperature fluctuations displayed here are 13.7 billion years old,
from the time when the Big Bang was thought to have occurred.
Essentially, it is a detailed, all-sky display of the young universe
developed from three years of WMAP data. The blue areas are cooler
while the red areas are warmer. The temperature range on this map is
± 200 microKelvin, which is incredibly small. The temperature range
is so small because it doesn’t measure absolute temperature but
anisotropy. Anisotropy is the difference between two measurements taken
in opposite directions. This is much more accurate than simply
measuring the absolute temperature in one direction. This data is used
to support the Big Bang theory using inflation. The concept is that the
universe expanded many trillion times its size in less than a trillionth
of a second at the beginning of the Big Bang. This is a map of the
remnant heat left from the big bang. According to NASA, the
measurements reveal size, matter content, age, geometry, and the fate of
the universe.
There are two versions of the WMAP data. This
dataset is from the third year of data collected
and is polarized and has a higher resolution. In the third year
dataset, the formation site of the Milky Way galaxy is visible in the
red band.
The other available dataset from the first year of data collected by WMAP and is lower
resolution.