HIP 85605

HIP 85605
Observation data
Epoch J2000      Equinox ICRS
Constellation Hercules
Right ascension 17h 29m 36.278s
Declination +24° 39′ 11.01″
Apparent magnitude (V) 11.03
Characteristics
Evolutionary stage red giant branch
Spectral type K4V
B−V color index 1.14
J−H color index 0.526
J−K color index 0.646
Astrometry
Radial velocity (Rv)−21.30±0.16 km/s
Proper motion (μ) RA: +4.837±0.008 mas/yr
Dec.: −8.718±0.011 mas/yr
Parallax (π)1.8860±0.0111 mas
Distance1,730 ± 10 ly
(530 ± 3 pc)
Details
Mass1.2 M☉
Radius5.7 R☉
Luminosity15.8±0.5 L☉
Surface gravity (log g)2.97 cgs
Temperature4,812±96 K
Other designations
2MASS J17293627+2439111, TYC 2079-1800-1, WDS J17296+2439B
Database references
SIMBADdata

HIP 85605 is a star in the constellation Hercules with a visual apparent magnitude of 11.03. It was once thought to be a M dwarf or K-type main-sequence star and a possible companion of the brighter star HIP 85607, but they are now known to be an optical double. Both objects are red giants separated by a greater distance than the original measurements indicated: HIP 85605 is 1,730±10 light years away while HIP 85607 is 1,323±13 light years away.

Distance estimation

The original Hipparcos parallax measurement in 1997 was 202 mas, which would have placed it 16.1 light-years from the Solar System. In 2007, van Leeuwen revised the number to 147 mas (0.147 arcseconds), or 22.2 light-years. With this new value, HIP 85605 would have been unlikely to be one of the 100 closest star systems to the Sun. In 2014, it was estimated that HIP 85605 could approach to about 0.13 to 0.65 light-years (0.04 to 0.2 pc) from the Sun within 240,000 to 470,000 years, assuming the then-known parallax and distance measurements to the object were correct. In that case its gravitational influence could have disrupted the orbits of comets in the Oort cloud and caused some of them to enter the inner Solar System.

With the release of Gaia DR2, it was determined that HIP 85605 is actually a much more distant 1,790±30 light-years away and will not be passing remotely close to the Sun at any point in time.

See also

References

  1. ↑ Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific. 99 (617): 695. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Constellation record for this object at VizieR.
  2. 1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. ↑ Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355. Bibcode:2000A&A...355L..27H.
  4. ↑ Pickles, A.; Depagne, É. (2010). "All-Sky Spectrally Matched UBVRI - ZY and u‧ g‧ r‧ i‧ z‧ Magnitudes for Stars in the Tycho2 Catalog". Publications of the Astronomical Society of the Pacific. 122 (898): 1437. arXiv:1011.2020. Bibcode:2010PASP..122.1437P. doi:10.1086/657947.
  5. ↑ Høg, E.; et al. (February 2000). "The Tycho-2 Catalogue of the 2.5 Million Brightest Stars". Astronomy and Astrophysics. 355 (1): L27–L30. Bibcode:2000A&A...355L..27H.
  6. 1 2 Cutri, Roc M.; Skrutskie, Michael F.; Van Dyk, Schuyler D.; Beichman, Charles A.; Carpenter, John M.; Chester, Thomas; Cambresy, Laurent; Evans, Tracey E.; Fowler, John W.; Gizis, John E.; Howard, Elizabeth V.; Huchra, John P.; Jarrett, Thomas H.; Kopan, Eugene L.; Kirkpatrick, J. Davy; Light, Robert M.; Marsh, Kenneth A.; McCallon, Howard L.; Schneider, Stephen E.; Stiening, Rae; Sykes, Matthew J.; Weinberg, Martin D.; Wheaton, William A.; Wheelock, Sherry L.; Zacarias, N. (2003). "VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". CDS/ADC Collection of Electronic Catalogues. 2246: II/246. Bibcode:2003yCat.2246....0C.
  7. 1 2 Khalatyan, A.; Anders, F.; Chiappini, C.; Queiroz, A. B. A.; Nepal, S.; Dal Ponte, M.; Jordi, C.; Guiglion, G.; Valentini, M.; Torralba Elipe, G.; Steinmetz, M.; Pantaleoni-González, M.; Malhotra, S.; Jiménez-Arranz, Ó.; Enke, H.; Casamiquela, L.; Ardèvol, J. (2024). "Transferring spectroscopic stellar labels to 217 million Gaia DR3 XP stars with SHBoost". Astronomy and Astrophysics. 691: A98. arXiv:2407.06963. Bibcode:2024A&A...691A..98K. doi:10.1051/0004-6361/202451427.
  8. 1 2 3 4 Hon, M.; Huber, D.; Kuszlewicz, J.S.; Stello, D.; Sharma, S.; Tayar, J.; Zinn, J.C.; Vrard, M.; Pinsonneault, M.H. (2023). "Oscillating red giants from the TESS QLP". VizieR On-line Data Catalog. Bibcode:2023yCat..19190131H. doi:10.26093/CDS/VIZIER.19190131.
  9. ↑ "HIP 85605". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved Sep 4, 2025.
  10. 1 2 Coryn A.L. Bailer-Jones (2015). "Close encounters of the stellar kind". Astronomy & Astrophysics. 575: A35. arXiv:1412.3648. Bibcode:2014yCat..35750035B. doi:10.1051/0004-6361/201425221. S2CID 59039482.
  11. ↑ Mamajek, Eric (2015-01-03). "Reason to Doubt the Hipparcos Distance and the Close Flyby Scenario for the "Rogue Star" HIP 85605". Figshare. doi:10.6084/m9.figshare.1284334. Retrieved 2025-09-04.
  12. ↑ Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  13. ↑ Perryman, M. A. C.; Lindegren, L.; Kovalevsky, J.; Hoeg, E.; Bastian, U.; Bernacca, P. L.; Crézé, M.; Donati, F.; Grenon, M.; Grewing, M.; van Leeuwen, F.; van der Marel, H.; Mignard, F.; Murray, C. A.; Le Poole, R. S.; Schrijver, H.; Turon, C.; Arenou, F.; Froeschlé, M.; Petersen, C. S. (July 1997). "The HIPPARCOS Catalogue". Astronomy & Astrophysics. 323: L49–L52. Bibcode:1997A&A...323L..49P.
  14. ↑ van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. ISSN 0004-6361.
  15. ↑ "THE ONE HUNDRED NEAREST STAR SYSTEMS". RECONS (Research Consortium On Nearby Stars). Retrieved 2015-01-12.
  16. ↑ Mamajek, Eric E.; Barenfeld, Scott A.; Ivanov, Valentin D. (2015). "The Closest Known Flyby of a Star to the Solar System". The Astrophysical Journal. 800 (1): L17. arXiv:1502.04655. Bibcode:2015ApJ...800L..17M. doi:10.1088/2041-8205/800/1/L17. S2CID 40618530.
  17. ↑ Coryn Bailer-Jones (2015-01-01). "The closest encounter is Hip 85605. How reliable is this?". Retrieved 2015-01-05.
  18. ↑ Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.