Circular No. 2209 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Cable Address: SATELLITES, NEWYORK Western Union: RAPID SATELLITE CAMBMASS REPORT ON THE 2.7-METER REFLECTOR Dr. Harlan J. Smith, Director of the McDonald Observatory, University of Texas, communicates the following: "In view of highly exaggerated and incorrect news stories of grave damage to the 2.7-m (107-inch) McDonald Observatory reflector, a prompt summary of the facts may be of interest to the astronomical community. Shortly before CST midnight Feb. 5 (Feb. 6 UT), a newly-hired employee fired seben point-blank shots into the front surface of the fused silica primary mirror, using a 9-mm pistol apparently brought with him from his previous home in the north. He has been committed by local authorities to a state mental institution, on ground of insanity. The harm suffered by the mirror from his bullets and his several preliminary blows with a hammer was extraordinarily small. The damage is limited to small craters about 3 to 5cm in radius, which reduce the light collecting efficiency by about 1 percent and introduce a very small amount of diffraction. Surface and Foucault examinations by Mr Donald Davidson and Dr. Robert Tull, the opticians responsible for producing the mirror, show that there is no change of figure. Astronomical observations of all types are essentially unimpaired by this tragic episode; the telescope resumed its observing program the following night, producing some of the best photographs (of quasar fields) so far obtained with this instrument in its first year of use". PERIODIC COMET CURJUMOV-GERASIMENKO (1969h) Further precise positions have been reported as follows: 1969/70 UT R.A. (1950) Decl. Mag. Observer Nov. 9.81944 10 18 05.92 +17 47 08.2 Candy Dec. 9.83229 11 12 07.25 +15 03 23.4 14 Seki 18.83652 11 22 07.90 +14 47 02.9 " 20.83576 11 23 55.72 +14 45 56.0 " Feb. 4.08359* 11 20 08.91 +18 01 42.0 Milet 4.09120* 11 20 07.81 +18 01 48.7 " 4.09466 11 20 07.76 +18 01 47.1 " M. P. Candy (Perth Observatory). 33-cm f/10 astrograph. T. Seki (Kochi Observatory). B. Milet (Nice Observatory). *Weak images. 1970 February 10 (2209) Brian G. Marsden
Our Web policy. Index to the CBAT/MPC/ICQ pages.