Note: this is an archived version which has been superseded. The current SNR catalogue is at

G111.7-2.1 Cassiopeia A, 3C461

Notes: Presumably the remnant of a late 17th century SN.

Radio: Bright shell with compact knots and extended plateau of emission.
Optical: Fast knots and quasi-stationary flocculli, with many filaments at large radii.
X-ray: Incomplete shell.
Distance: Optical expansion, plus proper motions indicate 2.8 kpc.


Last updated: 20 AUG 1996

Dave Green/MRAO, Cambridge, UK/