Cosmological microwaves, also known as the Cosmic Microwave Background (CMB), are a faint glow of radiation that permeates the universe, serving as a remnant from the Big Bang.
Discovered in 1965 by Arno Penzias and Robert Wilson, the CMB is one of the most compelling pieces of evidence for the Big Bang theory. This ancient radiation, now cooled to just 2.7 degrees above absolute zero, provides a snapshot of the universe when it was merely 380,000 years old, a time when atoms first formed and the universe became transparent to radiation.
The study of the CMB revolutionised our understanding of the cosmos. By analysing the tiny fluctuations in temperature and polarisation of the CMB, scientists mapped the early universe's density variations. These variations eventually led to the large-scale structures we see today, such as galaxies and clusters of galaxies.
The CMB allows cosmologists to measure key properties of the universe, including its age, composition, and rate of expansion. The precision of these measurements has significantly improved with missions like NASA's Wilkinson Microwave Anisotropy Probe (WMAP) and the European Space Agency's Planck satellite. These observations have provided a wealth of data, confirming the standard model of cosmology and offering insights into the nature of dark matter and dark energy.
In essence, cosmological microwaves are an amazing cosmic relic, offering us a direct link to the universe's past and continuing to illuminate the mysteries of its vast expanse.
Resources: