HR 2501

Last updated
HR 2501
HPCMaLightCurve.png
Light curves for HP Canis Majoris. The main plot, from Hipparcos data, [1] shows the long-term variability. The inset plot, from TESS data, [2] shows the short timescale variability.
Observation data
Epoch J2000.0        Equinox J2000.0
Constellation Canis Major
Right ascension 06h 45m 31.18877s [3]
Declination −30° 56′ 56.3297″ [3]
Apparent magnitude  (V)5.35 - 5.80 [4]
Characteristics
Spectral type B1.5 Vne [5]
U−B color index −0.89 [5]
B−V color index −0.19 [5]
Variable type γ Cas + λ Eri [6]
Astrometry
Proper motion (μ)RA: −3.284±0.084 [3]   mas/yr
Dec.: 4.630±0.098 [3]   mas/yr
Parallax (π)1.6500 ± 0.0895  mas [3]
Distance 2,000 ± 100  ly
(610 ± 30  pc)
Absolute magnitude  (MV)−3.23 [7]
Details
Mass 9.6 [8]   M☉
Radius 7.5 [3]   R☉
Luminosity 2,067 [9]   L☉
Surface gravity (log g)3.60 [3]   cgs
Temperature 22,070 [10]   K
Metallicity [Fe/H]+0.18 [3]   dex
Rotational velocity (v sin i)135 [10]  km/s
Age 23 [8]   Myr
Other designations
HP Canis Majoris, HD  49131, HIP  32385, SAO  197177 [11]
Database references
SIMBAD data

HR 2501, also known as HD 49131 and HP Canis Majoris, is a star about 2,000 light years from the Earth, in the constellation Canis Major. [3] It is a 5th magnitude star, so it will be faintly visible to the naked eye of an observer far from city lights. [3] It is a variable star, whose brightness varies from magnitude 5.35 to 5.80 on a variety of timescales ranging from hours to hundreds of days. [4] [12]

In 1838, John Herschel discovered that HR 2501 is a double star, with a magnitude 8.4 companion 4.9 arc seconds away. [13] The companion is a slightly less massive, cooler, and less luminous B-type main sequence star. [3] It is also a chemically peculiar helium-weak star. [5]

In 1977, Mikolaj Jerzykiewicz and Christiaan Sterken detected slight (0.12 magnitude) variability in the brightness of HR 2501 during their search for beta Cephei variable stars in the southern sky. [14] Christoffel Waelkens et al. confirmed that HR 2501 is variable in 1983, and reported that it varied in brightness on a timescale of weeks to months, with no clear period. [15] In 1986 it was given the variable star designation HP Canis Majoris. [16] In 1998, Anne-Marie Hubert and Michele Floquet examined the Hipparcos data for HR 2501, and found that it exhibited outbursts in which the brightness increased by 0.35 magnitudes, with a rise time of 100 days and a decay time of 400 days. [17]

In 1984, Christopher Corbally found that the spectrum HR 2501 shows Hα, Hβ, Hγ and Hδ emission features, which along with its spectral type makes it a Be star. [5] Jacqueline Coté found that the IRAS data for HR 2501 showed excess (above what would be expected from the star's photosphere) 12 and 25 μ emission. She concluded that this infrared excess could be due to either a circumstellar dust shell located 21 stellar radii from HR 2501, with a temperature of about 585 K, or (more likely) free-free emission from circumstellar gas. [18]

An extensive study of HR 2501, published in 2003 by Fabien Carrier and Gilbert Burki, found that the star exhibits several periodicities. The radial velocity varies by 20.5 km/sec with a period of 19.005±0.0091 hours. They confirm the roughly 500 day photometric period found earlier by Hubert and Floquet, and suggest these outbursts may arise from episodes of matter ejection from the star or disk formation. Finally, they found a low amplitude (0.065 magnitude) brightness oscillation with a period of 11.05 hours. Spectroscopic data were presented by Carrier and Burki which suggest that during the brightness outbursts, "blobs" of ejected matter can be detected moving through a Keplerian disk surrounding the star. [12]

Related Research Articles

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<span class="mw-page-title-main">AR Aurigae</span> Binary star system in the constellation Auriga

AR Aurigae, also known by its Flamsteed designation 17 Aurigae, is a binary star in the constellation Auriga. Based on parallax measurements made by the Hipparcos spacecraft, it is approximately 461 light-years from Earth.

<span class="mw-page-title-main">26 Canis Majoris</span> Star in the constellation Canis Major

26 Canis Majoris is a variable star in the southern constellation of Canis Major, located around 1,010 light years away from the Sun. It has the variable star designation MM Canis Majoris; 26 Canis Majoris is the Flamsteed designation. This object is visible to the naked eye as a dim, blue-white hued star with a baseline apparent visual magnitude of 5.89. It is moving further from the Earth with a heliocentric radial velocity of +22 km/s.

<span class="mw-page-title-main">27 Canis Majoris</span> Binary star system in the constellation Canis Major

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<span class="mw-page-title-main">Eta Canis Minoris</span> Binary star system in the constellation Canis Minor

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<span class="mw-page-title-main">DL Crucis</span> Star in the constellation Crux

DL Crucis is a variable star in the constellation Crux.

HD 36678 is single star in the northern constellation of Auriga. This star is dimly visible to the naked eye with an apparent visual magnitude of 5.83. It is located at a distance of approximately 840 light years from the Sun based on parallax.

Chi<sup>2</sup> Orionis Star in the constellation Orion

Chi2 Orionis is a B-type supergiant star in the constellation of Orion. It has an apparent visual magnitude of 4.63 but being quite distant, and heavily extinguished it burns with the greatest absolute visual light magnitude among stars in Orion within the near reaches of the galaxy, 0.9 of a magnitude brighter than Rigel. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. It is considered to be a member of the Gemini OB1 association.

<span class="mw-page-title-main">Zeta Chamaeleontis</span> Variable star in the constellation Chamaeleon

Zeta Chamaeleontis, Latinized from ζ Chamaeleontis, is a star located in the constellation Chamaeleon. Located around 570 light-years distant, it shines with a luminosity approximately 522 times that of the Sun and has a surface temperature of 15,655 K. South African Astronomer A.W.J. Cousins noted it to vary between magnitudes 5.06 and 5.17 in 1960. It was classified as a Beta Cephei variable in the Hipparcos and Tycho Catalogues, with a period of 1.07 days, before being reclassified as a slowly pulsating B star in the 2011 version. It is also an eclipsing binary star, with a period of 2.7 days.

<span class="mw-page-title-main">HD 54893</span> Star in the constellation Puppis

HD 54893, often called A Puppis is a suspected variable star in the constellation Puppis. Its apparent magnitude is 4.83 and is approximately 860 light years away based on parallax.

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<span class="mw-page-title-main">PX Andromedae</span> Star in the constellation Andromeda

PX Andromedae is an eclipsing cataclysmic variable star in the constellation Andromeda. It has been classified as a SW Sextantis variable, and its apparent visual magnitude varies between 14.04 and 17.

HD 76270, also known as HR 3544, is a solitary, white hued star located in the southern circumpolar constellation Volans. It has an apparent magnitude of 6.10, making it faintly visible to the naked eye if viewed under ideal conditions. The object is relatively far with a distance of 2,360 light years, but is slowly approaching the Solar System with a heliocentric radial velocity of −2.6 km/s.

<span class="mw-page-title-main">HU Tauri</span> Binary star in the constellation Taurus

HU Tauri is a tight binary star system in the equatorial constellation of Taurus. It is an eclipsing binary, which means that the member stars periodically eclipse each other every 2.056 days. They have a combined apparent visual magnitude of 5.85, which is bright enough to be dimly visible to the naked eye. During the primary eclipse, the magnitude drops to 6.68, while the secondary eclipse decreases the magnitude to 5.91. The distance to this system, based on parallax measurements, is approximately 414 light years.

<span class="mw-page-title-main">HD 44506</span> Star in the constellation of Columba

HD 44506 is a solitary, blue hued star located in the southern constellation Columba. The object is also called HR 2288, which is its Bright Star Catalog designation. It has an average apparent magnitude of 5.52, making it faintly visible to the naked eye under ideal conditions. HD 44506 is located relatively far at a distance of 1,800 light years based on Gaia DR3 parallax measurements but is receding with a heliocentric radial velocity of 54 km/s.

<span class="mw-page-title-main">FY Canis Majoris</span> Variable star in the constellation Canis Major

FY Canis Majoris, also known as HD 58978, is a star about 1,800 light years from the Earth, in the constellation Canis Major. It is usually a 5th magnitude star, so it will be visible to the naked eye of an observer far from city lights. It is a Gamma Cassiopeiae variable star, whose brightness varies from magnitude 4.8 to 6.25.

<span class="mw-page-title-main">V2052 Ophiuchi</span> Variable star in the constellation Ophiuchus

V2052 Ophiuchi, also known as HR 6684, is a star about 920 light years from Earth in the constellation Ophiuchus. It is a 5th-magnitude star, making it faintly visible to the naked eye of an observer far from city lights. V2052 Ophiuchi is a Beta Cephei variable star, varying slightly in brightness from magnitude 5.81 to 5.84 over a period of about 3.4 hours.

<span class="mw-page-title-main">HR 5907</span> Star in the constellation Scorpius

HR 5907, also known as V1040 Scorpii and HD 142184, is a star about 470 light years from the Earth, in the constellation Scorpius. It is a 5th magnitude star, so it will be faintly visible to the naked eye of an observer far from city lights. Its brightness varies slightly, ranging from magnitude 5.39 to 5.43 every 12 hours and 20 minutes. HR 5907 is a member of the Scorpius–Centaurus association.

References

  1. ↑ EAS (1997). "The HIPPARCOS and TYCHO catalogues". Astrometric and Photometric Star Catalogues Derived from the ESA Hipparcos Space Astrometry Mission. ESA SP Series. Noordwijk, Netherlands: ESA Publications Division. 1200. Bibcode:1997ESASP1200.....E. ISBN   9290923997 . Retrieved 15 October 2022.
  2. ↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 19 February 2023.
  3. 1 2 3 4 5 6 7 8 9 10 11 Vallenari, A.; et al. (Gaia Collaboration) (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics . arXiv: 2208.00211 . doi: 10.1051/0004-6361/202243940 . Gaia DR3 record for this source at VizieR.
  4. 1 2 N. N. Samus; O. V. Durlevich; et al. "V918 Sco database entry". Combined General Catalog of Variable Stars (2017 ed.). CDS . Retrieved 2023-02-21.
  5. 1 2 3 4 5 Corbally, C. J. (August 1984). "Close visual binaries.I.MK classifications". Astrophysical Journal Supplement Series. 55: 657–677. Bibcode:1984ApJS...55..657C. doi:10.1086/190973 . Retrieved 23 February 2023.
  6. ↑ "HP CMa". The International Variable Star Index. AAVSO. Retrieved 22 February 2023.
  7. ↑ Melnik, A. M.; Dambis, A. K. (2020). "Distance scale for high-luminosity stars in OB associations and in field with Gaia DR2. Spurious systematic motions". Astrophysics and Space Science. 365 (7): 112. arXiv: 2006.14649 . Bibcode:2020Ap&SS.365..112M. doi:10.1007/s10509-020-03827-0. S2CID   220128144.
  8. 1 2 Tetzlaff, N.; et al. (January 2011). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1): 190–200. arXiv: 1007.4883 . Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. S2CID   118629873.
  9. ↑ McDonald, I.; Zijlstra, A. A.; Watson, R. A. (15 June 2017). "Fundamental parameters and infrared excesses of Tycho–Gaia stars". Monthly Notices of the Royal Astronomical Society. 471 (1): 770–791. arXiv: 1706.02208 . Bibcode:2017MNRAS.471..770M. doi: 10.1093/mnras/stx1433 . eISSN   1365-2966. ISSN   0035-8711.
  10. 1 2 Zorec, J.; et al. (November 2016). "Critical study of the distribution of rotational velocities of Be stars. I. Deconvolution methods, effects due to gravity darkening, macroturbulence, and binarity". Astronomy & Astrophysics. 595: 26. Bibcode:2016A&A...595A.132Z. doi: 10.1051/0004-6361/201628760 .
  11. ↑ "HD 49131 -- Be Star". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2023-02-21.
  12. 1 2 Carrier, F.; Burki, G. (April 2003). "Outbursts in the Be star HR 2501". Astronomy and Astrophysics. 401: 271–279. Bibcode:2003A&A...401..271C. doi:10.1051/0004-6361:20030125 . Retrieved 22 February 2023.
  13. ↑ Worley, C. E.; Douglass, G. G. (November 1997). "The Washington Double Star Catalog (WDS, 1996.0)". Astronomy and Astrophysics Supplement Series. 125 (3): 523. Bibcode:1997A&AS..125..523W. doi:10.1051/aas:1997239 . Retrieved 23 February 2023.
  14. ↑ Jerzykiewicz, M.; Sterken, C. (1977). "Search for beta Cephei stars south of declination -20 . I. Incidence of light variability among early B giants and subgiants - summer objects". Acta Astron. 27: 365–387. Bibcode:1977AcA....27..365J . Retrieved 23 February 2023.
  15. ↑ Waelkens, C.; Rufener, F.; Burnet, M. (1983). "Photometric variations of some early Be stars". Hvar Observatory Bulletin. 7 (1): 125–130. Bibcode:1983HvaOB...7..125W . Retrieved 23 February 2023.
  16. ↑ Kholopov, P. N.; Samus, N. N.; Kazarovets, E. V.; Kireeva, N. N. (August 1987). "The 68th Name-List of Variable Stars" (PDF). Information Bulletin on Variable Stars. 3058: 1. Bibcode:1987IBVS.3058....1K . Retrieved 23 February 2023.
  17. ↑ Hubert, A. M.; Floquet, M. (July 1998). "Investigation of the variability of bright Be stars using HIPPARCOS photometry". Astronomy and Astrophysics. 335: 565–572. Bibcode:1998A&A...335..565H . Retrieved 23 February 2023.
  18. ↑ Coté, J. (July 1987). "B and A type stars with unexpectedly large colour excesses at IRAS wavelengths". Astronomy and Astrophysics. 181: 77–84. Bibcode:1987A&A...181...77C . Retrieved 23 February 2023.
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