Epsilon Eridani
| Epsilon Eridani | |
| Stellar characteristics | |
|---|---|
| Constellation | Eridanus |
| Right ascension (Epoch J2000) | 03h 32m 55.8442s |
| Declination (Epoch J2000) | -09° 27' 29.744" |
| Spectral type | K2V |
| Distance from Sol | 10.5 ± 0.03 ly |
| Other designations | 18 Eridani, BD -09°697, GCTP 742.00, GJ 144, HD 22049, HIP 16537, HR 1084, LHS 1557, SAO 130564, WDS 03330-0928. |
| Planets | Epsilon Eridani b |
Epsilon Eridani is located only about 10.5 light-years (ly) away in the northeastern part of the constellation Eridanus, the River. Somewhat smaller and cooler than our own Sun, Sol, Epsilon Eridani is also less luminous. In Earth's night sky, however, it is clearly visible to the naked eye as the third closest star viewable without a telescope.
The Epilson Eridani system has two asteroid belts made of rocky and metallic debris left over from the early stages of planetary formation[1]. The innermost debris belt is located roughly around the same position as the Main Asteroid Belt in our solar system and is rich in silicate dust[2], while the second, denser belt (which is also mostly likely to be composed of bodies rich in rock as well as ices) lies between the first belt and a broad, outer ring of icy bodies at 35 to 90 AUs out from Epsilon Eridani that is similar to the Solar System's Edgeworth-Kuiper Belt.
This main sequence, orange-red dwarf (K2 V) is a relative young star that may be around 850 million years old, within the range between 500 million to a billion years old[2][3][4]. It may have about 83 (+/- 0.05) to 85 percent of Sol's mass[3][5], 84 percent of its diameter[6], but only about 27.8 percent of its luminosity[7].
The distance from Epsilon Eridani where an Earth-type rocky planet may have liquid water on its surface may have to be between 0.47 and 0.91 AU[8] -- between the orbital distances of Mercury and Earth in the Solar System. In that distance range from the star, such a planet would have an orbital period shorter an Earth year.
Known Places Around Epsilon Eridani
- Starbase 3 (Fenspace Infinities)
- Epsilon Eridani b A Jupiter class planet with a mass of about 1.55 times that of Jupiter. Its orbit has an average radius of 3.39 AUs and takes about 6.9 years to complete. At its maximum distance of 5.8 AU from its primary any water on its moons would freeze. However, under certain conditions life could survive in these circumstances.
Notes
- ↑ (Spitzer press release)
- ↑ 2.0 2.1 (Backman et al, 2008)
- ↑ 3.0 3.1 (Benedict et al, 2006)
- ↑ (Saffe et al, 2005)
- ↑ (RECONS)
- ↑ (Johnson and Wright, 1983, page 653)
- ↑ (Saumon et al, 1996, page 17)
- ↑ (Jones and Sleep, 2003)
