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Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
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We present an analysis of new and existing photometric and spectroscopicobservations of the ongoing eruption in the symbiotic star AG Pegasi,showing that this binary has evolved considerably since the turn of thecentury. Recent dramatic changes in both the UV continuum and the windfrom the hot component allow a more detailed analysis than in previouspapers. AG Peg is composed of a normal M3 giant and a hot, compact starembedded in a dense, ionized nebula. The hot component powers theactivity observed in this system, including a dense wind and aphotoionized region within the outer atmosphere of the red giant. Thehot component contracted in radius at roughly constant luminosity from1850 to 1985. Its bolometric luminosity declined by a factor of about 4during the past 5 yr. Both the mass loss rate from the hot component andthe emission activity decreased in step with the hot component's totalluminosity, while photospheric radiation from the red giant companionremained essentially constant.
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Datos observacionales y astrométricos
| Constelación: | Pegaso |
| Ascensión Recta: | 21h51m51.91s |
| Declinación: | +11°05'28.5" |
| Magnitud Aparente: | 6.653 |
| Distancia: | 71.633 parsecs |
| Movimiento Propio en Ascensión Recta: | 75.1 |
| Movimiento Propio en Declinación: | 25.2 |
| B-T magnitude: | 6.962 |
| V-T magnitude: | 6.679 |
Catálogos y designaciones:
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