The Discovery of WMAP
Back in 2001, NASA launched the Wilkinson Microwave Anisotropy Probe (WMAP) satellite, with the goal of studying the cosmic microwave background radiation (CMB). The mission aimed to measure the temperature and polarization of the CMB and help us understand the early universe.
WMAP was a successor to the Cosmic Background Explorer (COBE) mission, which was launched in 1989. COBE provided the first evidence of the CMB, but WMAP’s more precise measurements helped us learn even more about the universe.
What is the Cosmic Microwave Background Radiation?
The cosmic microwave background radiation is the afterglow of the Big Bang. It’s the oldest light in the universe, and it permeates all of space. The CMB was first detected in 1964 by Arno Penzias and Robert Wilson at Bell Labs, and it has been studied ever since.
The CMB is incredibly uniform, with tiny fluctuations in temperature and polarization. These fluctuations are caused by variations in the density of matter in the early universe, and they provide a glimpse into the conditions that existed when the universe was just a few hundred thousand years old.
What Did WMAP Discover?
WMAP’s measurements provided a wealth of information about the universe. Here are some of the key discoveries:
1. The Age of the Universe
WMAP helped us determine the age of the universe with unprecedented accuracy. The satellite measured the temperature of the CMB to be 2.725 Kelvin, which allowed us to calculate the age of the universe to be about 13.8 billion years.
2. The Composition of the Universe
WMAP also helped us understand the composition of the universe. The satellite measured the amount of dark matter and dark energy in the universe, which make up about 95% of its total mass-energy. This has major implications for our understanding of the universe’s evolution and eventual fate.
3. Inflationary Cosmology
One of the most exciting discoveries from WMAP was evidence for inflationary cosmology. Inflation is a theory that suggests the universe underwent a period of exponential expansion in the first fraction of a second after the Big Bang. WMAP’s measurements of the CMB provided strong support for this theory.
What’s Next for CMB Research?
WMAP’s mission ended in 2010, but its legacy lives on. The European Space Agency’s Planck satellite carried on where WMAP left off, providing even more precise measurements of the CMB. And in the future, there are plans for even more ambitious CMB missions, such as the Cosmic Origins Explorer (COrE) and the Primordial Inflation Explorer (PIXIE).
Q&A
Q: What is the CMB?
A: The cosmic microwave background radiation is the afterglow of the Big Bang. It’s the oldest light in the universe, and it permeates all of space. The CMB was first detected in 1964 by Arno Penzias and Robert Wilson at Bell Labs, and it has been studied ever since.
Q: What did WMAP discover?
A: WMAP made many important discoveries, including the age and composition of the universe and evidence for inflationary cosmology. Its measurements of the CMB provided unprecedented insights into the early universe.
Q: What’s next for CMB research?
A: There are plans for even more ambitious CMB missions in the future, such as the Cosmic Origins Explorer (COrE) and the Primordial Inflation Explorer (PIXIE).
