BD +6°398
 There's something missing here…This page is a Wikipedia or SolStation data dump with little or no relation – or, worse yet, possibly with contradictions – to the situation in Fenspace. You can help FenWiki by expanding this page. |
| BD +6°398 A | |
| Stellar characteristics | |
|---|---|
| Constellation | Cetus |
| Right ascension (Epoch J2000) | 2h 36m 4.9s |
| Declination (Epoch J2000) | +6° 53' 12.7" |
| Spectral type | M3.5 Vn |
| Distance from Sol | 23.8 ± 0.2 ly |
| Other designations | HR 753* A, Gl 105 A, Hip 12114, HD 16160, BD+06 398, SAO 110636, FK5 1073, G 73-70, G 76-11, LHS 15, LTT 10858, LFT 217. |
| BD +6°398 B | |
| Stellar characteristics | |
|---|---|
| Constellation | Cetus |
| Right ascension (Epoch J2000) | 2h 36m 15s |
| Declination (Epoch J2000) | +06° 52′ 18″ |
| Spectral type | M3.5 Vn |
| Distance from Sol | 23.8 ± 0.2 ly |
| Other designations | BX Ceti, HR 5568 B, Gl 105 B, HD 16160 B, BD+06 398 B, G 73-71, G 76-12, LHS 16, LTT 10859, LFT 218, Vys or McC 396, Rob 153. |
| BD +6°398 C | |
| Stellar characteristics | |
|---|---|
| Constellation | Cetus |
| Right ascension (Epoch J2000) | 02h 35m 58.8s |
| Declination (Epoch J2000) | +06° 52′ 00″ |
| Spectral type | M7 V |
| Distance from Sol | 23.8 ± 0.2 ly |
| Other designations | HR 753 C, Gl 105 C |
Also known as Gliese 105, this triple star system is located 23.5 ly away from Sol. It lies in the northern edge of the constellation Cetus, the Whale. Many astronomers now refer to this star system by its designation in the famous Gliese Catalogue of Nearby Stars [1] of Wilhelm Gliese (1915-93), who was a longtime astronomer at the Astronomiches Rechen-Institut at Heidelberg (even when it was at Berlin).
Star A was found to have a distant, proper motion companion "B" by Adriaan van Maanen (1884-1946) before March 1938 [2]. However, a second, closer but unseen companion "C" to Star A had been on the astrometric program at Sproul Observatory (Swarthmore College) since 1937[3]. In 1994, David Golimowski and collaborators at the Palomar Observatory in California visually detected the third stellar member to Gliese 105[4]. While Star C is a much closer stellar companion of Star A than Star B, it apparently lies near the theoretical minimum mass limit of 0.75 to 0.80 Solar for core fusion of hydrogen
Contents
BD +6°398 A
Star A is a main sequence, orange-red dwarf of spectral and luminosity type K3 V. It may have around 81 percent of Sol's mass, 85 percent of its diameter, and only 21 percent of its luminosity. Star A's late spectral type and dim luminosity puts it possibly close to the lower limit of habitability for (multicellular) Earth-type plant and animal life, given the redness of its light and the increased risk of tidal locking from the closeness of the orbit necessary for liquid water on a planetary surface. The distance from Star A where an Earth-type planet would be "comfortable" with liquid water is centered around 0.45 AU -- within the orbital distance of Mercury in the Solar System. At that distance from the star, such a planet would have an orbital period of about 124 days, or around a third of an Earth year.
BD +6°398 B
This star is a red dwarf of spectral and luminosity type M3.5 Vn. It has about 21 percent of Sol's mass, 28 percent of its diameter, and 1/1000th of its brightness. The SIMBAD Astronomical Database identifies Star B as a variable star with the designation BX Ceti. Despite its variability, the star has "anomalously low" chromospheric and coronal activity[5]. For Star B, the water-zone orbit lies around 0.031 AU. As a result, a planet in such an orbit would have a period of only about 4.3 days. Tidal locking of such a closely orbiting planet would resulting in perpetual day on one side and perpetual night on the other.
BD +6°398 C
An extremely dim red dwarf, Star C is of spectral and luminosity type M7 V with only about 8.2 percent of Sol's mass, (Golimowski et al, 2000, in ps; and 1995). In addition, Star C may have a diameter not much larger than Jupiter's and only around 7.5 one-millionth of its visual luminosity. For Star C, the water zone orbit lies only around 0.0027 AU, even closer than for Star B. A planet in such an orbit would have a period of only around 14 hours. Again, tidal locking of such a closely orbiting planet would resulting in perpetual day on one side and perpetual night on the other.
(Data from SolStation.com)
Notes
- ↑ (CNS, now ARICNS database)
- ↑ (object Number 3 in Table 2 on page 33)
- ↑ (Sarah Lee Lippincott, 1973)
- ↑ (Golimowski et al, 1995; and May, 1995)
- ↑ (Doyle et al, 1998)
