HD 74423

HD 74423

A light curve for HD 74423 plotted from TESS data
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Volans
Right ascension 08h 40m 17.985s
Declination −64° 50′ 16.84″
Apparent magnitude (V) 8.58–8.66
Characteristics
Evolutionary stage main sequence
Spectral type A7VkA0mA0 λ Boo
Apparent magnitude (B) 8.81±0.02
Apparent magnitude (J) 8.065±0.020
Apparent magnitude (H) 8.021±0.067
Apparent magnitude (K) 7.944±0.040
Variable type α2 CVn or Ellipsoidal and δ Sct
Astrometry
Proper motion (μ) RA: −9.719 mas/yr
Dec.: 11.732 mas/yr
Parallax (π)2.1018±0.0150 mas
Distance1,550 ± 10 ly
(476 ± 3 pc)
Details
primary
Mass2.1 M☉
Radius3.3 R☉
Surface gravity (log g)3.6 cgs
Temperature7,900 K
Metallicity [Fe/H]−1.0 dex
secondary
Mass2.0 M☉
Radius3.2 R☉
Surface gravity (log g)3.6 cgs
Temperature7,600 K
Metallicity [Fe/H]−1.0 dex
Age800 Myr
Other designations
HD 74423, CD−64°342, SAO 250298, TYC 8934-1662-1, TIC 355151781
Database references
SIMBADdata

HD 74423 is a heartbeat binary star and one component pulsates on only one hemisphere. This is caused by tidal interaction with its partner. The star is located in the constellation Volans.

HD 74423 is slightly variable in brightness. It fluctuates between magnitudes 8.58 and 8.66 every 19 hours. The exact variability type is unclear. It was initially found in a search for α2 Canum Venaticorum variables and assumed to be one, but has since been considered to be a δ Scuti variable. The spectrum shows unusually strong absorption lines of some iron peak elements, a characteristic of λ Boötis stars. Both components are thought to show the chemical peculiarity.

References

  1. ↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
  2. ↑ Staff (2 August 2008). "Finding the constellation which contains given sky coordinates". DJM.cc. Retrieved 31 July 2020.
  3. 1 2 3 4 5 6 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.
  4. 1 2 3 Bernhard, K.; Hümmerich, S.; Otero, S.; Paunzen, E. (2015). "A search for photometric variability in magnetic chemically peculiar stars using ASAS-3 data". Astronomy and Astrophysics. 581: A138. arXiv:1507.01112. Bibcode:2015A&A...581A.138B. doi:10.1051/0004-6361/201526424. S2CID 54062866.
  5. 1 2 3 4 5 Gray, R. O.; Riggs, Q. S.; Koen, C.; Murphy, S. J.; Newsome, I. M.; Corbally, C. J.; Cheng, K. -P.; Neff, J. E. (2017). "The Discovery of λ Bootis Stars: The Southern Survey I". The Astronomical Journal. 154 (1): 31. Bibcode:2017AJ....154...31G. doi:10.3847/1538-3881/aa6d5e.
  6. 1 2 3 4 "HD 74423 -- Star". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 31 July 2020.
  7. 1 2 3 4 5 Handler, G.; Kurtz, D. W.; Rappaport, S. A.; Saio, H.; Fuller, J.; Jones, D.; Guo, Z.; Chowdhury, S.; Sowicka, P.; Aliçavuş, F. Kahraman; Streamer, M. (9 March 2020). "Tidally trapped pulsations in a close binary star system discovered by TESS". Nature Astronomy. 4 (7): 684–689. arXiv:2003.04071. Bibcode:2020NatAs...4..684H. doi:10.1038/s41550-020-1035-1. ISSN 2397-3366. S2CID 212634328.
  8. 1 2 3 4 5 6 Fuller, J.; Kurtz, D. W.; Handler, G.; Rappaport, S. (2020). "Tidally trapped pulsations in binary stars". Monthly Notices of the Royal Astronomical Society. 498 (4): 5730. arXiv:2008.02836. Bibcode:2020MNRAS.498.5730F. doi:10.1093/mnras/staa2376.