Currently the expanding cloud from the supernova remnant is about 10 light years across.
A supernova
SN 1572 or Tycho's Supernova was a supernova type Ia, in the constellation Cassiopeia
Cassiopeia A is a supernova remnant in the constellation Cassiopeia.It has no single point of luminosity, so no definitive magnitude can be attributed to it.
its very big
The North Star, Polaris, is about half-way between the Big Dipper and Cassiopeia.
Cassiopeia A is a supernova remnant in the constellation Cassiopeia.It has no single point of luminosity, so no definitive magnitude can be attributed to it.
Although not noted as a supernova, the nebula "Cassiopeia A" was first observed by John Flamsteed on August 16, 1680. It is likely that intervening dust clouds obscured the brightness of the supernova, which might otherwise have been observed in 1667.Current estimates place the distance from Earth as around 11,000 light years. If that is correct, then the supernova explosion actually took place around 9,000 BCE. (see related link)
Black Hole Blast Off Big Bang
Supernova - 2005 Big Red 2-3 is rated/received certificates of: Australia:M
There are more than five stars in Cassiopeia but the major ones are as follows from the left of the 'W' / 'M': Caph, Beta Cassiopeia Shedar, Alpha Cassiopeia Cih, Gamma Cassiopeia Ruchbah, Delta Cassiopeia Sagin, Epsilon Cassiopeia
Supernova stars' are at least three times the solar mass of the Sun.
Big History - 2013 Silver Supernova - 1.15 was released on: USA: 21 December 2013