HR 7703

HR 7703
Observation data
Epoch J2000      Equinox J2000
Constellation Sagittarius
Right ascension 20h 11m 11.93827s[1]
Declination –36° 06′ 04.3610″[1]
Apparent magnitude (V) 5.31[2]/11.50[3]
Characteristics
Spectral type K2.5 V[4] + M4 V[5]
U−B color index +0.43[2]
B−V color index +0.85[2]
Astrometry
Radial velocity (Rv)–129.4[6] km/s
Proper motion (μ) RA: +456.99[1] mas/yr
Dec.: –1574.64[1] mas/yr
Parallax (π)166.3272 ± 0.1065 mas[7]
Distance19.61 ± 0.01 ly
(6.012 ± 0.004 pc)
Absolute magnitude (MV)6.53[8]
Details
HR 7703 A
Mass0.65[9] M☉
Radius0.66[9] R☉
Luminosity0.26[9] L☉
Surface gravity (log g)4.48 ± 0.17[9] cgs
Temperature5,075 ± 43[9] K
Metallicity [Fe/H]–0.56 ± 0.04[9] dex
Rotational velocity (v sin i)1.8 ± 0.2[8] km/s
Age7.7[10] Gyr
HR 7703 B
Mass0.24[11] M☉
Radius0.28[3] R☉
Other designations
279 G. Sagittarii, Gliese 783, CD –36°13940, GCTP 4782.00, HD 191408, HIP 99461, SAO 211885.[12]
HR 7703 A: LHS 486, LFT 1529, LTT 7988
HR 7703 B: LHS 487, LFT 1530, LTT 7989
Database references
SIMBADThe system
A
B
HR 7703 is located in the constellation Sagittarius
HR 7703 is located in the constellation Sagittarius
HR 7703
Location of HR 7703 in the constellation Sagittarius

HR 7703 (Gliese 783, 279 G. Sagittarii) is a binary star system in the constellation of Sagittarius. The brighter component has an apparent visual magnitude of 5.31,[2] which means it is visible from suburban skies at night. The two stars are separated by an angle of 7.10″, which corresponds to an estimated semimajor axis of 56.30 AU for their orbit.[11]

Based upon an annual parallax shift of 0.16625 arc seconds as measured by the Hipparcos satellite, this system is 19.62 light-years (6.015 parsecs) from Earth. It is approaching the Solar System at a velocity of approximately 129 kilometers per second.[6] At this rate, it will make its closest approach in 41,100 years when it comes to within 6.7 light-years (2.05 parsecs) of the Sun.[13]

This star system has been examined for an excess of radiation in the infrared. The presence of an infrared excess can be taken as an indication of a debris disk orbiting the star. However, no such excess was discovered around HR 7703.[14] Radial velocity data collected over a period of 12 years was examined for signs of periodicity caused by a planet orbiting at a distance of 3–6 AU, but none was detected.[15] A slight linear trend in the radial velocities of the primary is probably due to the companion star.[16]

  1. ^ a b c d Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference ibsh8_30 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference CADARS was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference aj132_1_161 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference APJSS149_2_423 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference aaa418_989 was invoked but never defined (see the help page).
  7. ^ Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  8. ^ a b Cite error: The named reference AmmlerVonEiff2012 was invoked but never defined (see the help page).
  9. ^ a b c d e f Cite error: The named reference apj720_2_1290 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference MH08 was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference aaa468_2_721 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference arXiv1003.2160 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference apj674_2_1086 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Wittenmyer2011 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Howard2016 was invoked but never defined (see the help page).