HD 156846

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Stern
HD 156846
AladinLite
Observation
dates equinoxJ2000.0 , epoch : J2000.0
Constellation Snake bearer
Right ascension 17 h 20 m 34.31 s
declination -19 ° 20 ′ 1.5 ″
Apparent brightness 6.5 mag
Typing
B − V color index +0.58 
Spectral class G1 V
Astrometry
Radial velocity (−68.6 ± 0.3) km / s
parallax (21.00 ± 0.51)  mas
distance (155 ± 4)  ly
(48 ± 1)  pc  
Visual absolute brightness M vis +3.1 mag
Proper movement 
Rec. Share: (−136.65 ± 0.61)  mas / a
Dec. portion: (−144.25 ± 0.29)  mas / a
Physical Properties
Dimensions 1.43  M
Effective temperature 6138  K
Metallicity [Fe / H] 0.22
Age 2.1 · 10 9  a
Other names
and catalog entries
Bright Star Catalog HR 6441 [1]
Henry Draper Catalog HD 156846 [2]
Hipparcos catalog HIP 84856 [3]
SAO catalog SAO 160474 [4]
Tycho catalog TYC 6242-339-1 [5]Template: Infobox star / maintenance / specification of the TYC catalog

HD 156846 is a yellow dwarf in the constellation Ophiuchus. It has an apparent magnitude of 6.5 mag.

In 2007, Omer Tamuz discovered, using the radial velocity method, a substellar companion that orbits this star and bears the systematic name HD 156846 b . The orbital period of the companion is around 360 days and its major semi-axis measures approximately one astronomical unit , but with an uncertainty between 0.15 and 1.83 AU. Since the orbital inclination of the object to the central star is also not known, one can only estimate its minimum mass. This is 10.5 masses of Jupiter. Since this only corresponds exactly in the (unlikely) case, if we were to look directly at the polar plane of the system, the real mass of the object should be significantly higher, so it should probably be a brown dwarf, but it still remains that Possibility of an exoplanet open. If the actual semi-major axis of HD 156846 b lies in the outer area of ​​the above-mentioned uncertainty zone, the object would even be in the habitable zone of its central star with some certainty.

Web links

Individual evidence

  1. a b c Hipparcos catalog (ESA 1997)
  2. Bright Star Catalog
  3. Pulkovo radial velocities for 35493 HIP stars
  4. a b c Hipparcos, the New Reduction (van Leeuwen, 2007)