CCD Astrometry of Critical List'' Minor Planets
Session 43 -- SL-9, Comets, Solar System
Display presentation, Tuesday, 10, 1995, 9:20am - 6:30pm

## [43.11] CCD Astrometry of Critical List'' Minor Planets

A.K.B. Monet (U.S. Naval Observatory Flagstaff Station)

Minor planet observations are being made at the USNO Flagstaff Station with an 8-inch transit telescope with a CCD camera operated in scan mode. Telescope operation is completely automatic and is monitored remotely by an observer using another telescope at the station. On a typical night, 80 to 100 objects are observed. Positions are determined with respect to the Guide Star Catalog (GSC) stars appearing in each frame, and are generally accurate to $\pm$0.3 arcseconds. All results are published, usually within a few weeks after observation, in the Minor Planet Center (MPC) circulars.

When this project began in March 1994, the plan was to do follow--on astrometry of recently--discovered near--Earth objects (NEOs). But the capacity of this observing program far exceeds the number of available NEOs. So the observing list was expanded to include several other categories of objects and projects, including minor planets of particular scientific interest, mass--determination candidates, objects which can be used to improved the dynamical reference frame, and MPC Critical List'' objects --- minor planets whose orbits and positions are especially in need of improvement. This paper will report on the progress to date in this last category of observation, on the quality of the results, and on some of the science being done or planned for the near future.