How bright was the crab nebula?

Answer 1

from sci-tech encyclopedia http://content.answers.com/main/content/img/McGrawHill/Encyclopedia/images/CE166300FG0010.gif The Crab Nebula is the remnant of a tremendous stellar explosion witnessed by Chinese astronomers in 1054. The explosion, called a supernova, occurred at a distance of about 2000 parsecs from the Earth (1 parsec = 1.9 × 1013 mi = 3.1 × 1013 km = 3.26 light-years). The Crab now consists of three components. At the heart of the nebula is what is left of the core of the Crab's giant stellar progenitor. This neutron star has twice the mass of the Sun concentrated into an object only about 20 km (12 mi) across, giving it a density of 109 tons per cubic centimeter. The neutron star is spinning at 30 times a second, whipping its powerful (108 tesla) magnetic field around with it. Radiation formed in this extreme environment is concentrated into two intense beams directed away from the neutron star's two magnetic poles. As these beams sweep past the direction of the Earth like the beam from a lighthouse, the star appears to wink on and off, earning it the name "pulsar." The Crab pulsar has been seen in all parts of the electromagnetic spectrum from gamma rays through radio waves. The Crab pulsar's rotational period is slowing by 34 nanoseconds a day, and as it slows it loses 100,000 times more power than is radiated away by the Sun. Most of this energy is carried away from the pulsar by a wind of electrons and positrons moving at close to the speed of light. The wind feeds a vast cloud of highly relativistic particles. This cloud is called the Crab synchrotron nebula because, as the particles spiral through the nebula's magnetic field, they give off the sort of radiation emitted by a synchroton particle accelerator. . The third component of the Crab is a complex of filaments made up of gas ejected by the explosion itself (see illustration). The filaments are ionized by ultraviolet radiation from the synchrotron nebula, causing them to glow like the gas in a fluorescent light bulb

Answer 2

The Crab Nebula is within our own Milky Way Galaxy, but at a distance of about 6500 light years from Earth.

Answer 3

The Crab Nebula is a supernova remenant from a star that exploded in the year 1054. It was recorded by Chinese and Arab astronomers.

Answer 4

Highly unlikely. At the centre of the crab nebula there is a neutron star.

Answer 5

Clouds of dust and gas

Answer 6

5h 34m 31.97s, +22° 00′ 52.1″

Answer 7

Very bright

Answer 8

Taurus