Citation
Abstract
The performance of the University of California at San Diego (UCSD) Table Mountain telescope has been evaluated to determine the potential of such an instrudifferential positions of stars at the meridian. The Ronchi technique is summarized in this article, and the operational features of the Table Mountain instrument are described. Results from an analytic model, simulations, and actual data are presented that characterize the telescope’s current performance. For a star pair of visual magnitude 7, the differential uncertainty of a 5-min observation is about 50 nrad (10 marcsec), and tropospheric fluctuations are the dominant error source. (approximately 170 marcsec). This magnitude is equivalent to that of a 2-W laser with a 0.4-m aperture transmitting to Earth from a spacecraft at Saturn. Photoelectron noise is the dominant error source for stars of visual magnitude 8.5 and fainter. If the photoelectron noise is reduced, ultimately tropospheric fluctuations will be the limiting source of error at an average level of 35 nrad (7 marcsec) for stars approximately 0.25 deg apart. Three near-term strategies are proposed for efficiency of the optics, masking background starlight, and averaging tropospheric fluctuations over multiple observations.
Details
- Volume
- 42-110
- Published
- August 15, 1992
- Pages
- 104–117
- File Size
- 711.8 KB