Astrometry of SN 1987A and Sanduleak -69 202.
Abstract
Photographic plates and CCD frames are used to determine accurate positions for SN 1987A and three components of the Sanduleak-69 202 system. Results give a position of the SN of RA = 5 h 35 min 49.992 sec, and declination = -69 deg, 17 arcmin, 58.08 arcsec (1950.0), confirming the near-coincidence between the SN and star 1 of Sanduleak-69 202. It is suggested that neither of the companions (star 2 and star 3) can be the progenitor. For star 2, a U value of about 14.5 and a spectral type near B0 V are found. Sanduleak-69 202 does not exhibit any variability at the 0.5-mag level, and its measured UBVRI magnitudes are in good agreement with those of a reddened B3 Ia star at the LMC distance. No evidence for a fourth star is found.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- May 1987
- Bibcode:
- 1987A&A...177L...1W
- Keywords:
-
- Astrometry;
- Astronomical Coordinates;
- Supernova 1987a;
- Astronomical Photometry;
- Photographic Plates;
- Position (Location);
- Stellar Magnitude;
- Ultraviolet Spectra;
- Astronomy