Note: this is an archived version which has been superseded.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, and NE `jet'.
X-ray: Incomplete shell, with hard spectral component, and compact central source.
Distance: Optical expansion, plus proper motions indicate 3.4 kpc.


Last updated: 26 Nov 2001

Dave Green/MRAO, Cambridge, UK/