This program is under development.
The following poster paper has been presented at the 189th meeting of the
American Astronomical Society
(AAS) in January 1997.
A New Astrometric Survey of the Southern Hemisphere
Gauss, F. S., Zacharais, N., Rafferty, T.J., Germain, M. E.,
Holdenried, E.R., Pohlman, J.W., and Zacharias, M.I.,
U.S. Naval Observatory
Abstract.
With the advent of space-based star catalogs of unprecedented accuracy
and the measurement of the Palomar Schmidt Survey plates, there is a
pressing need for a new high-quality catalog covering the stars in the
intermediate magnitudes. Testing with the USNO 8-inch CCD astrograph,
equipped with a new, 5-element lens and a small CCD camera have shown
that accuracies of 20mas or better can be obtained in a reasonable
time using a two-fold overlap method. A grating allows stars as
bright as 6th magnitude to be observed at the same time as the
faintest stars. A program is planned to start within a year in the
Southern Hemisphere using this telescope and a new 4K CCD camera. The
goal is to produce an astrometric catalog of all stars down to 15th
magnitude in a period of two years.
USNO CCD Astrometric Catalog - South
(UCAC-S)
- To produce a high density catalog of reference stars in the
Southern Hemisphere between magnitudes 7 and 16 with accuracies
of ~20 mas at epoch
- http://ad.usno.navy.mil/proj/UCAC/
Project Plan
- 2-fold overlap
- preliminary reduction with Tycho stars
- direct link to Hipparcos stars
- link to extra-galactic sources
- with global block adjustment
- start summer 97
- one color only
Projected Accuracy
USNO 8-inch CCD Astrograph
- built as
- Boller and Chivens Twin Astrograph
- yellow and blue lenses
- new red-corrected 8-inch lens
- yellow lens used as 8-inch guidescope
- SBIG ST-4 autoguider
- embedded single-board control computer
Picture of the telescope
Description of optics and camera
Camera Picture
Characteristics and Data of UCAC-S
Sky coverage
Computer control
Catalog Properties
- positions better than Tycho for 9th magnitude and fainter at epoch 1997
- improved proper motions for all stars in catalog
- 4x greater density than GSC - ~2000/sq. deg
- preliminary data available as observations progress
Applications
- dense, accurate general reference stars
- bridge Hipparcos/Tycho to faint photographic surveys
- reference stars for NEOs predictions
- improved Schmidt plate reductions
- Sloan Digital Sky Survey astrometric reduction of individual photometric chips
- reference stars for IR surveys (DENIS, 2MASS) at about same epoch
- input catalog for future space missions