The problem of the sighting line stabilization for axial meridian circles

✍ Scribed by P. F. Lazorenko; A. V. Sergeev

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 523 KB
• Volume: 316
• Category: Article
• ISSN: 0004-6337
• DOI: 10.1002/asna.2103160212

✦ Synopsis

The paper deals with the method based on treating the axial meridian circle and a long-focus light mark in the prime vertical as a single virtual instrument that has properties of meridian circle. A horizontal axis, a sighting line, and a micrometer cross-wire of the instrument are created by optical means. The key function here is performed by the light mark that ensures a reference direction used for formation of instrumental ljlrincipal planes and directions. Stability of instrumental azimuth, inclination, and collimation is expected to be about f O . 01. Besides, an accuracy of observations is not affected by any temperature and weight deformations of telescope mechanics. Owing to the last circumstance, the design is cheap and the telescope aperture may be increased significantly, to about lm. An estimate of accuracg of obserYFtions depends on the adopted model of image motion, and for sites with excellent seeing and bright stars is fO. 03 to fO. 05 (rms).