Cassiopeia A - supernova remnant nebula
Cassiopeia A , is a supernova remnant nebula located in the constellation Cassiopeia .
Cassiopeia A is magnitude and is 5" in size. For reference, the full moon is 30' (arc minutes) or 0.5° in size.
- Cassiopeia A
- supernova remnant nebula
* One can see up to magnitude 7-8 objects with perfect eyes under ideal dark sky conditions.