Taurus AThe radio source in the constellation Taurus that is identified with the Crab nebula. It has a flux density at 178 megahertz of 1420 jansky, most of which comes from synchrotron emission in the nebula, which is a supernova remnant. A small fraction of the radio flux is pulsed, due to the pulsar in the nebula rotating about 30 times per second. Unlike other supernova remnants, such as Cassiopeia A, the Crab nebula does not have a regular ringlike radio structure, probably because of its internal energy source – the pulsar.
Taurus A[′tȯr·əs ′ā]
A strong, discrete radio source in the constellation Taurus, associated with the Crab Nebula.