Crab Nebula (M 1)

The Crab Nebula (M1, NGC 1952, Taurus A) is a supernova and pulsar remnant in the constellation Taurus. The nebula was formed by a bright supernova explosion that was recorded in 1054 by various observers, including Chinese, Japanese, and Arab astronomers. This explosion was visible even in the daytime and left behind a nebula that remains an important object of research.

Historical discovery

• John Bevis discovered the nebula in 1731.
• In 1758, Charles Messier independently discovered it and included it in his catalog as the first cloud resembling a comet.
• The nebula was studied by William Herschel in the late 18th century. - William Parsons, 3rd Earl of Rosse, made a drawing of the nebula in 1842–43 using his 36-inch telescope, resembling a crab, hence the name.

Supernova Connection

The Crab Nebula is the remnant of a supernova that was recorded in 1054 as a "guest star". Historical records by Chinese astronomers and Japanese observers confirmed the appearance of a bright star that was visible for several weeks, even during the day.

In 1921, scientists confirmed the nebula's connection to the events of 1054 when they noticed that the nebula was expanding, indicating a recent explosion.

Pulsar in the center of the nebula

At the center of the Crab Nebula is a pulsar (PSR B0531+21) - a neutron star with a diameter of about 25 km. This star rotates at a speed of 30 revolutions per second. The pulsar emits radiation in the range from gamma rays to radio waves.

In 1968, a key discovery was made when two rapidly variable radio sources were detected in the region of the nebula, and one of them was identified as a pulsar. This discovery confirmed that pulsars are not white dwarfs, as previously thought, but rotating neutron stars.

High-energy radiation

The Crab Nebula is one of the brightest sources of gamma radiation. In 1989, it became the first astronomical object confirmed as a source of high-energy gamma radiation above 100 GeV. In 2019, the nebula was detected as a gamma-ray source with energies exceeding 100 TeV.

Importance for Science

Studying the Crab Nebula and the pulsar allows astronomers to probe in depth the physical processes that occur in extreme environments, such as supernova explosions and the magnetic fields of neutron stars. These studies help to understand the processes that occur in stellar systems and in galaxies.

The Crab Nebula continues to be an object of observation for both professional astronomers and amateur astronomers, inspiring scientific research and the popularization of astronomy around the world.