44 Tauri, also known as HD 1287 and IM Tauri, is a star located about 210 light years from the Earth, in the constellation Taurus.[3] It is a 5th magnitude star, making it faintly visible to the naked eye of an observer located far from city lights. It is a Delta Scuti variable star, ranging between magnitude 5.37 and 5.58 over a period of about 3.5 hours.[4]

44 Tauri

A light curve for IM Tauri, plotted from TESS data.[1] The 3.479 hour period[2] is marked in red.
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Taurus
Right ascension 04h 10m 49.86084s[3]
Declination +26° 28′ 51.4365″[3]
Apparent magnitude (V) 5.37 - 5.58[4]
Characteristics
Spectral type F2 IV[5]
Variable type δ Scuti[4]
Astrometry
Radial velocity (Rv)17.43±0.64[3] km/s
Proper motion (μ) RA: −30.919±0.123[3] mas/yr
Dec.: −35.105±0.072[3] mas/yr
Parallax (π)15.4199 ± 0.0863 mas[3]
Distance212 ± 1 ly
(64.9 ± 0.4 pc)
Absolute magnitude (MV)1.44±0.16[6]
Details
Primary
Mass1.89[6] M
Surface gravity (log g)3.6±0.1[5] cgs
Temperature7000±200[7] K
Rotational velocity (v sin i)2±1[7] km/s
Other designations
p Tauri, IM Tauri, BD+26 411, HIP 19513, HD 26322, HR 1287, SAO 76485[8]
Database references
SIMBADdata

In 1966, Ivan Danziger and Robert Dickens discovered that 44 Tauri was a low amplitude variable star, with a period of approximately 3.22 hours.[9] In a follow-up study published the next year, they reported that the period was irregular, indicating beat phenomena, and they classified it as a δ Scuti variable.[10] In 1968, 44 Tauri was given the variable star designation IM Tauri.[11]

44 Tauri has been a popular object for detailed astroseismic and spectroscopic studies, because its very slow (relative to other δ Scuti stars) rotation speed of 3±2 km/sec does not complicate pulsation mode identification or greatly broaden spectral lines.[5][7][12] As of 2010, 44 Tauri had been found to pulsate with 15 independent periods, ranging from 1.89 to 4.52 hours.[5]

References

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  1. ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 16 January 2023.
  2. ^ "IM Tau". The International Variable Star Index. AAVSO. Retrieved 19 January 2023.
  3. ^ a b c d e f g 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. ^ a b c Samus', N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.
  5. ^ a b c d Lenz, P.; Pamyatnykh, A. A.; Zdravkov, T.; Breger, M. (January 2010). "A δ Scuti star in the post-MS contraction phase: 44 Tauri" (PDF). Astronomy and Astrophysics. 509: A90. arXiv:0911.4339. Bibcode:2010A&A...509A..90L. doi:10.1051/0004-6361/200912914. S2CID 119311255. Retrieved 19 January 2023.
  6. ^ a b Civelek, R.; Kızıloğlu, N.; Kırbıyık, H. (October 2001). "Radial and Nonradial Oscillations of 44 Tauri". The Astronomical Journal. 122 (4): 2042–2046. Bibcode:2001AJ....122.2042C. doi:10.1086/323078. S2CID 122087742.
  7. ^ a b c Lenz, P.; Pamyatnykh, A. A.; Zdravkov, T.; Breger, M. (August 2007). "High-resolution spectroscopy of the δ Scuti star 44 Tauri: photospheric element abundances and mode identification" (PDF). Astronomy and Astrophysics. 471 (1): 237–245. arXiv:0911.4339. Bibcode:2010A&A...509A..90L. doi:10.1051/0004-6361/200912914. S2CID 119311255. Retrieved 19 January 2023.
  8. ^ "p Tau -- delta Sct Variable". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-01-19.
  9. ^ Danziger, I. J.; Dickens, R. J. (August 1966). "Observations of Variable F-Type Stars with Short Periods". Information Bulletin on Variable Stars. 150: 1. Bibcode:1966IBVS..150....1D. Retrieved 19 January 2023.
  10. ^ Danziger, I. J.; Dickens, R. J. (July 1967). "Spectrophotometry of New Short-Period Variable Stars". Astrophysical Journal. 149: 55–72. Bibcode:1967ApJ...149...55D. doi:10.1086/149231.
  11. ^ Kukarkin, B. V.; Efremov, Yu. N.; Frolov, M. S.; Medvedeva, G. I.; Kholopov, P. N.; Kurochkin, N. E.; Kukarkina, N. P.; Perova, N. B.; Fedorovich, V. P. (November 1968). "Identification List of the New Variable Stars Nominated in 1968". Information Bulletin on Variable Stars. 311: 1. Bibcode:1968IBVS..311....1K. Retrieved 19 January 2023.
  12. ^ Zima, W.; Lehmann, H.; Stütz, Ch.; Ilyin, I. V.; Breger, M. (August 2007). "High-resolution spectroscopy of the δ Scuti star 44 Tauri: photospheric element abundances and mode identification" (PDF). Astronomy and Astrophysics. 471 (1): 237–245. Bibcode:2007A&A...471..237Z. doi:10.1051/0004-6361:20077201. Retrieved 19 January 2023.