Gravitational Lensing by a Massive Black Hole at the Galactic Center
Abstract
The manifestations of gravitational lensing by a massive black hole at the Galactic center, with particular attention given to lensing of stars in the stellar cluster that lie behind Sgr A*, and of Sgr A east, a nonthermal extended radio source which is known with certainty to lie behind the Galactic center. Lensing of the stellar cluster produces a deficit of stellar images within 10 mas of the center, and a surplus between 30 and 300 mas. The results suggest that the proper motion of the stars will produce brightness variations of stellar images on a time scale of a few years or less. Both images of such a source should be visible, and will rise and fall in luminosity together.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1992
- DOI:
- 10.1086/186306
- Bibcode:
- 1992ApJ...387L..65W
- Keywords:
-
- Black Holes (Astronomy);
- Galactic Nuclei;
- Gravitational Lenses;
- Milky Way Galaxy;
- Star Clusters;
- Infrared Stars;
- Radio Astronomy;
- Stellar Luminosity;
- Very Long Base Interferometry;
- Astrophysics;
- GALAXY: CENTER;
- COSMOLOGY: GRAVITATIONAL LENSING;
- INFRARED: STARS;
- RADIO CONTINUUM: INTERSTELLAR