Epsilon Reticuli
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| Observation data Epoch J2000 |
|
|---|---|
| Constellation (pronunciation) |
Reticulum |
| Right ascension | 4h 16m 29.03s |
| Declination | -59° 18′ 07.76″ |
| Apparent magnitude (V) | 4.44 / 12.5 |
| Characteristics | |
| Spectral type | K2IVa / D |
| Astrometry | |
| Distance | 59.45 ly (18.23 pc) |
| Other designations | |
|
HR 1355, HD 27442, HIP 19921
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| Database references | |
| SIMBAD | data |
Epsilon Reticuli is a binary system approximately 59 light-years away in the constellation of Reticulum. The primary star is an orange subgiant star, while the secondary star is a white dwarf star. The primary star should be easily visible without optical aid under dark skies in southern hemisphere. As of 2000, an extrasolar planet has been confirmed to be orbiting the primary star in the system.
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[edit] Star system
The primary star, Epsilon Reticuli A, is an orange subgiant 20% more massive than our Sun. Being a subgiant it is ceasing or has already ceased fusing hydrogen in its core. Soon the star will swell up and become a red giant. Despite its advanced stage, it cannot be much older than the Sun.
The companion star, Epsilon Reticuli B, is a white dwarf star located around 240 AU from Epsilon Reticuli A. It has a surface temperature between 9000 and 17000 K.
[edit] Planetary system
On December 11, 2000, a team of astronomers announced the discovery of a planet Epsilon Reticuli b. With a minimum mass of 1.17 that of Jupiter and a similar radius, the planet moves around Epsilon Reticuli with an average separation of 1.16 AUs. The eccentricity of the planet is extremely low (at 0.06), and orbits around the star every 418 days (or 1.13 years).
| Planet (in order from star) |
Mass (MJ) |
Orbital period (days) |
Semimajor axis (AU) |
Eccentricity |
|---|---|---|---|---|
| b | >1.56±0.14 | 428.1±1.1 | 1.271±0.073 | 0.060±0.043 |
[edit] References
- Butler et al. (2001). "Two New Planets from the Anglo-Australian Planet Search". The Astrophysical Journal 555 (1): 410 – 417. doi:.
[edit] External links
- Epsilon Reticulum. Interstellar Card. Retrieved on 2008-06-11.
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