HD 49798
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Stern HD 49798 |
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| AladinLite | |||||||||||
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Observation dates equinox : J2000.0 , epoch : J2000.0 |
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| Constellation | Aft deck of the ship | ||||||||||
| Right ascension | 06 h 48 m 4.7 s | ||||||||||
| declination | -44 ° 18 ′ 58.4 ″ | ||||||||||
| Apparent brightness | 8.28 likes | ||||||||||
| Typing | |||||||||||
| B − V color index | −0.29 | ||||||||||
| Spectral class | O6 | ||||||||||
| Astrometry | |||||||||||
| Radial velocity | (13.5 ± 4.5) km / s | ||||||||||
| Proper movement | |||||||||||
| Rec. Share: | (−4.73 ± 0.53) mas / a | ||||||||||
| Dec. portion: | (5.39 ± 0.52) mas / a | ||||||||||
| Physical Properties | |||||||||||
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Other names and catalog entries |
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HD 49798 is a about 650 parsecs from Earth distant star in the constellation Puppis . It has an apparent magnitude of 8.3 mag.
In 1997, scientists discovered an unidentifiable X-ray source called RX J0648.0–4418 near it. Only the XMM-Newtonian space telescope was able to identify the object causing the radiation. It is a massive white dwarf with about 1.3 solar masses that orbits HD 49798 and rotates once around its axis every 13 seconds. It is thus about to explode (on astronomical timescales) as a Type Ia supernova .
Web links
- HD 49798 (ESO)
- HD 49798 (SIMBAD)
- The Discovery of 13 second X-Ray Pulsations from the Hydrogen-depleted Subdwarf O6 Star Binary HD 49798
- HD 49798, a New O-Type Subdwarf
Individual evidence
- ↑ a b c Hipparcos catalog (ESA 1997)
- ↑ Pulkovo radial velocities for 35493 HIP stars
- ^ Hipparcos, the New Reduction (van Leeuwen, 2007)
- ↑ White dwarf is about to explode