Furuhjelm 46

Furuhjelm 46
Observation data
Epoch J2000      Equinox J2000
Constellation Hercules
Right ascension 17h 12m 07.91s
Declination +45° 39′ 57.2″
Apparent magnitude (V) 10.02/10.25
Characteristics
Spectral type M3 + M3.5
Astrometry
Radial velocity (Rv)–19 ± 5 km/s
Proper motion (μ) RA: +348.59 ± 5.68 mas/yr
Dec.: –1624.84 ± 6.80 mas/yr
Parallax (π)156.66 ± 1.37 mas[1]
Distance20.8 ± 0.2 ly
(6.38 ± 0.06 pc)
Orbit[2]
Period (P)12.9512 ± 0.0096 yr
Semi-major axis (a)0.7620 ± 0.0015″
Eccentricity (e)0.7430 ± 0.008
Inclination (i)149.14 ± 0.25°
Longitude of the node (Ω)160.0 ± 1.3°
Periastron epoch (T)1991.032 ± 0.011[3]
Argument of periastron (ω)
(secondary)		99.0 ± 1.0°
Details
Temperature3,272 ± 28[4] K
Metallicity [Fe/H]–0.31 ± 0.17[4] dex
Other designations
BD+45° 2505, HD 155876, HIP 84140, WDS 17121+5450, KUI 79
Gl 661 A: LFT 1326, LTT 15095, LHS 433, NLTT 44362
Gl 661 B: LFT 1327, LTT 15096, LHS 434, NLTT 44363
Database references
SIMBADThe system
A
B
Furuhjelm 46 is located in the constellation Hercules
Furuhjelm 46 is located in the constellation Hercules
Furuhjelm 46
Location of Furuhjelm 46 in the constellation Hercules

Furuhjelm 46, also known as HD 155876 and Gliese 661, is a nearby binary star system, consisting of two very similar red dwarfs, located in the constellation Hercules.

The star's duplicity was discovered by the Dutch astronomer Gerard Kuiper in 1934 in a systematic survey for duplicity of the known stars within about 25 parsecs from the Sun, carried out with the 36-inch telescope of the Lick Observatory.[5] Furuhjelm 46 is the nearest "true" (i. e. not brown dwarf) star system in Hercules, however, there is brown dwarf in this constellation, located closer: WISE 1741+2553.

  1. ^ Cite error: The named reference Söderhjelm1999 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference aj111_370 was invoked but never defined (see the help page).
  3. ^ Fractional Besselian year.
  4. ^ a b Cite error: The named reference apj748_2_934 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference 1934PASP_46_235K was invoked but never defined (see the help page).