S Andromedae: Supernova 1885 in M31

Supernova 1885, also later named S Andromedae (for the second variable to be discovered in constellation Andromeda), was the first supernova discovered beyond our Milky Way galaxy, on August 20, 1885, by Ernst Hartwig (1851-1923) at Dorpat Observatory in Estonia. It reached mag 6 between August 17 and 20, and it was independently found by several observers. However, only Hartwig realized its significance. It faded to mag 16 in February 1890.

It is the only supernova to now to have been recorded in the Andromeda galaxy, M31.

The remnant of SN 1885 was discovered more than 100 years later by R.A. Fesen et.al. (1989) with the 4-m Mayall telesope of Kitt Peak National Observatory on CCD exposures taken on November 10, 1988, using narrow band interference filters, because of its absorption caused by iron atoms (Fe I). Hamilton and Fesen (1999) have used the Hubble Space Telescope to image absorption of this supernova remnant, and found its diameter to be 0.55 +/- 0.15 arc seconds in the light of Fe II. They calculated from these observations that this remnant contains between 0.1 and 1.0 solar masses of iron.

  • Dead Link! Kevin McLin's S Andromeda and SNR 1885 page. Kevin gives a fuller account to the discovery, observation and classification of both the supernova and its remnant.
  • SIMBAD data for SN 1885
  • NED data for SN 1885


    Hartmut Frommert
    Christine Kronberg

    [SEDS] [MAA] [Home] [Back to M31]

    Last Modification: February 24, 2006