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Far-ultraviolet imagery of a 20 deg diameter field in Sagittarius,centered near (1950) R.A. 18 h 34 m, decl. -30 deg 25 arcmin, wasobtained by the S201 far-ultraviolet camera during the Apollo 16mission. In a 10-minute exposure covering the 1250-1600 A wavelengthrange, 1034 star images are detectable, with a limiting ultravioletmagnitude of about 10. Most of these objects are identified withearly-type stars listed in the Smithsonian Astrophysical ObservatoryStar Catalog, the Catalog of Stellar Identifications, or both, but 203objects remain unidentified or are identified with late-type stars. Thephotometric measurements appear to be in reasonable agreement with thoseof the International Ultraviolet Explorer for stars in common, and withexpectations for A0 stars. A detailed photometric study was made of theMessier 8 region, and it is concluded that dust-scattered starlightcontributes about half of the total radiation observed from the centralregion of M8.
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Datos observacionales y astrométricos
| Constelación: | Sagitario |
| Ascensión Recta: | 18h33m39.76s |
| Declinación: | -36°48'20.3" |
| Magnitud Aparente: | 7.971 |
| Distancia: | 296.736 parsecs |
| Movimiento Propio en Ascensión Recta: | -2.2 |
| Movimiento Propio en Declinación: | -12.1 |
| B-T magnitude: | 7.921 |
| V-T magnitude: | 7.967 |
Catálogos y designaciones:
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