Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Leo |
Right ascension | 11h 47m 40.74723s[1] |
Declination | +00° 15′ 20.1018″[1] |
Apparent magnitude (V) | 13.34[2] |
Characteristics | |
Spectral type | M4V[3] |
V−R color index | +1.22[4] |
R−I color index | +1.55[4] |
Variable type | Flare star |
Astrometry | |
Radial velocity (Rv) | 7.02 ± 0.32[5] km/s |
Proper motion (μ) | RA: −314.284 mas/yr[1] Dec.: −100.757 mas/yr[1] |
Parallax (π) | 53.1361 ± 0.0304 mas[1] |
Distance | 61.38 ± 0.04 ly (18.82 ± 0.01 pc) |
Details | |
Surface gravity (log g) | 4.5[6] cgs |
Temperature | 3100[6] K |
Metallicity | 0.23[3] |
Rotational velocity (v sin i) | 5.60 ± 1.40[5] km/s |
Other designations | |
Database references | |
SIMBAD | data |
ARICNS | data |
GJ 3685 is a star in the constellation of Leo. It is extremely faint; its apparent magnitude is 13.3,[2] and can only be seen with a ten-inch (25 cm) telescope (see Limiting magnitude). Based on a parallax of 53.1361 milliarcseconds,[1] the system is located 61.4 light-years (18.8 parsecs) away from the Earth.
This is a part of a binary star system consisting of two components separated by 24″.[8] The primary component, GJ 3685 (also known as GJ 3685 A), is a very old red dwarf that is also a flare star. A 20-minute flare was observed in 2004 by the GALEX satellite.[9] Its companion, GJ 3686, is another faint red dwarf with a spectral type of M5. It is also known as LP 613-50 and is also located roughly the same distance as its primary.[10]