Moonwatch
Moonwatch was an artificial satellite observation organization founded by Fred Whipple of the Smithsonian Institution in 1956 and which existed until around 1980.
The program was aimed at amateur astronomers and those interested in space travel all over the world and supported the participants with data and, in some cases, with measuring instruments in order to be able to determine precise orbital elements of difficult-to-observe satellites . Similar programs also existed in the Soviet Union .
Initially, the earth satellites were observed in small groups, each of which observed an overlapping section of the sky with a powerful Apogee telescope (see picture). Because the orbital data were still imprecise and the satellite passages were also relatively "unpunctual". Later, when good forecasting programs were also available, the work shifted to individual observers. Many of the telescopes then quickly received swiveling azimuthal mounts from military stocks.
In the early 1970s , several hundred groups worked at Moonwatch worldwide, including around 15 in Germany and 3 in Austria. The measurements were the basis of many scientific investigations, in particular of satellites with low perigee , so-called "Low Perigee Objects". Such bodies can hardly be photographed by satellite cameras as they are only visible at dusk .
The accuracy of the measurements was checked using a few satellites with stable orbits and was - depending on the equipment and experience of the observer - between 10 "and about 5 '. Some observed with binoculars in front of the star background , others with theodolite- like instruments or powerful ones Apogee telescopes : The program also included the observation of re-entry of satellites into the earth's atmosphere.
See also
literature
- Nelson Hayes: Trackers of the Skies . Howard Doyle Publ. 1968 and Academic Press 1975
- SAO Moonwatch Center: Moonwatch Newsletters 1965–1975
- Günter Seeber: Satellite Geodesy . De Gruyter-Verlag 1989