Research activities can be divided into four fields:

1: Observations on Mt Wilson with the MKIII optical interferometer,
   which is operated on a rotating basis by personnel based at NRL;
2: Reduction of interferometric data of binary stars and
   the determination of their orbits;
3: Reduction of astrometric data and determination of the positions of 
   stars;
4: Radioastronomical research on the jets of quasars.

ad 1: Five trips to Mt Wilson, CA, were made, each lasting about
      two weeks. Data taken with the MKIII instrument provides the
      basis of research fields 2 and 3. Responsibility for the
      scheduling of binary observations has been taken over.
ad 2: A database of calibrated visibilities has been compiled, covering
      all binary related observations of the last four years. It was
      used to assess the status of the binary project and to select
      binaries for more detailed observations. New programs have been
      written and added to the software, which allowed to determine
      six more orbits of spectroscopic binaries. The results of this
      work was presented in a poster at the "ESO Conference on High 
      Resolution Imaging by Interferometry", held in Munich, October 
      14 to 18, 1991.
ad 3: Reduction of astrometric data accumulated over the last three
      years was begun by modifying, complementing and compiling programs 
      written at USNO. The software is being tested and improved at the time.
ad 4: A paper on radioastronomical observations of a quasar, obtained
      while graduating at the University of Bonn, was completed, in 
      collaboration with NRL co-workers. Follow-up observations with
      the VLA were made and reduced during a stay at NRAO, Socorro.