3 Geminorum

Last updated
3 Geminorum
Gemini constellation map.svg
Red circle.svg
Location of 3 Gem (circled)
Observation data
Epoch J2000.0        Equinox J2000.0 (ICRS)
Constellation Gemini
Right ascension 06h 09m 43.9853s [1]
Declination +23° 06′ 48.472″ [1]
Apparent magnitude  (V)5.71 - 5.77 [2]
Characteristics
Evolutionary stage Blue supergiant star
Spectral type B3Ia [3]
U−B color index −0.63 [4]
B−V color index +0.21 [4]
Variable type α Cyg [5] [2]
Astrometry
Radial velocity (Rv)16.00±4.3 [6]  km/s
Proper motion (μ)RA: −0.064 [1]   mas/yr
Dec.: −2.685 [1]   mas/yr
Parallax (π)0.3878 ± 0.0616  mas [1]
Distance approx. 8,000  ly
(approx. 2,600  pc)
Absolute magnitude  (MV)−6.26 [7]
Details
Mass 21 [7]   M☉
Radius 55 [8]   R☉
Luminosity 204,000 [8]   L☉
Surface gravity (log g)2.45 [8]   cgs
Temperature 16,500 [8]   K
Rotational velocity (v sin i)80 [8]  km/s
Other designations
3  Geminorum, PU  Gem, HR  2173, HIP  29225, HD  42087, BD+23°1226, AAVSO  0603+23
Database references
SIMBAD data

3 Geminorum is a blue supergiant star in the constellation Gemini. It is a small amplitude pulsating variable and a close double star, with a mean combined apparent visual magnitude of about 5.7.

A light curve for PU Geminorum, plotted from Hipparcos data PUGemLightCurve.png
A light curve for PU Geminorum, plotted from Hipparcos data

3 Geminorum was found to be an α Cygni variable in 1998 and given the designation PU Geminorum. It varies by a few tenths of a magnitude [5] with a main period of 6.807 days [2] and a secondary period of 25 days. [8]

3 Geminorum is also a close double star. The brighter component is the variable blue supergiant. The companion is 2.5 magnitudes fainter. The separation is about 0.6 arc-seconds. [10] There is also a much fainter, approximately 14th magnitude, star 14" away. [11]

Faint Hα emission lines have been detected in the spectrum of 3 Geminorum, [12] but this is not usually expressed in published spectral classifications. [3] An "e" is only occasionally appended to the spectral type to reflect the emission lines. [13] [5] 3 Geminorum has frequently been classified as a normal supergiant (luminosity class Ib), [14] although a bright supergiant (Ia) luminosity class is now preferred. [3]

3 Geminorum can be occulted by the Moon. Observations of these occultations can give information about the angular diameter of a star, or about close companions. Occultations of 3 Geminorum have been observed, but no double or diameter information has been published. [15]

Related Research Articles

<span class="mw-page-title-main">V533 Carinae</span> Star in the constellation Carina

V533 Carinae is a A-type supergiant and a Alpha Cygni variable star with a mean apparent magnitude of +4.59 in the constellation Carina. It is located at a distance of about 13,000 light years.

<span class="mw-page-title-main">119 Tauri</span> Star in the constellation Taurus

119 Tauri is a red supergiant star in the constellation Taurus. It is a semiregular variable and its angular diameter has been measured at about 10 mas. It is a similar star to Betelgeuse although redder and more distant.

Omicron<sup>1</sup> Centauri Star in the constellation Centaurus

Omicron1 Centauri is a star in the constellation Centaurus. It is approximately 10,000 light years from Earth.

KW Sagittarii is a red supergiant star, located approximately 2,420 parsecs away from the Sun in the direction of the constellation Sagittarius. It is one of the largest known stars, with a diameter about 1,000 times larger than the Sun. If placed at the center of the Solar System, the star's surface would engulf Mars, coming close to Jupiter's orbit.

<span class="mw-page-title-main">Zeta Cephei</span> Star in the constellation Cepheus

Zeta Cephei is a red supergiant star, located about 1000 light-years away in the constellation of Cepheus. Zeta Cephei marks the left shoulder of Cepheus, the King of Ethiopia. It is one of the fundamental stars of the MK spectral sequence, defined as type K1.5 Ib.

<span class="mw-page-title-main">1 Vulpeculae</span> Star in the constellation Vulpecula

1 Vulpeculae is a class B4IV star in the constellation Vulpecula. Its apparent magnitude is 4.77 and it is approximately 780 light years away based on parallax.

<span class="mw-page-title-main">NO Aurigae</span> Star in the constellation Auriga

NO Aurigae is a pulsating variable star in the constellation Auriga. It is an unusually-luminous asymptotic giant branch star about 3,500 light years away.

<span class="mw-page-title-main">6 Cassiopeiae</span> Star in the constellation Cassiopeia

6 Cassiopeiae is a white hypergiant in the constellation Cassiopeia, and a small-amplitude variable star.

<span class="mw-page-title-main">V381 Cephei</span> Triple star system in the constellation Cepheus

V381 Cephei is a triple star system in the northern constellation of Cepheus. Its apparent magnitude is slightly variable between 5.5 and 5.7.

<span class="mw-page-title-main">5 Lacertae</span> Star in the constellation Lacerta

5 Lacertae is a spectroscopic binary in the constellation Lacerta. Its apparent magnitude is 4.36.

<span class="mw-page-title-main">Sigma Ophiuchi</span> Star in the constellation Ophiuchus

Sigma Ophiuchi, Latinized from σ Ophiuchi, is a single, orange-hued star in the equatorial constellation Ophiuchus. Its apparent visual magnitude is 4.31, which is bright enough to be faintly visible to the naked eye. The annual parallax shift of 3.62 mas as seen from Earth provides a distance estimate of roughly 900 light years. It is moving closer to the Sun with a radial velocity of −28 km/s.

<span class="mw-page-title-main">1 Puppis</span> Star in the constellation Puppis

1 Puppis is a single star in the southern constellation of Puppis. It lies in the northern part of the constellation at a distance of about 790 ly, east of Aludra in Canis Major and just north of the white supergiant, 3 Puppis. This object is visible to the naked eye as a faint, red-hued star with an apparent visual magnitude of 4.59. It is moving further from the Earth with a heliocentric radial velocity of +32.4 km/s.

<span class="mw-page-title-main">V1073 Scorpii</span> Variable star in the constellation Scorpius

V1073 Scorpii is a variable star in the constellation Scorpius. It has a non-Greek Bayer designation of k Scorpii. The star has a blue-white hue and is visible to the naked eye with an apparent visual magnitude that fluctuates around +4.87. Parallax measurements yield a distance estimate of approximately 2,920 ly (896 pc) from the Sun, and it is drifting further away with a radial velocity of +7 km/s. It has an absolute magnitude of −6.8

<span class="mw-page-title-main">Y Centauri</span> Variable star in the constellation Centaurus

Y Centauri or Y Cen is a semiregular variable star in the constellation of Centaurus.

<span class="mw-page-title-main">10 Persei</span> Blue supergiant star in the constellation Perseus

10 Persei is a blue supergiant star in the constellation Perseus. Its apparent magnitude is 6.26 although it is slightly variable.

<span class="mw-page-title-main">Y Lyncis</span> Variable star in the constellation Lynx

Y Lyncis is a semiregular variable star in the constellation Lynx. It is an asymptotic giant branch star of spectral type M6S, with a luminosity class of Ib, indicating a supergiant luminosity. It is around 1,160 light years away.

<span class="mw-page-title-main">V520 Persei</span> Star in the constellation Perseus

V520 Persei is a blue supergiant member of NGC 869, one of the Perseus Double Cluster open clusters. It is an irregular variable star. At a magnitude of 6.55, V520 Persei is the brightest member in either NGC 869 or NGC 884, although the brighter HD 13994 lies in the foreground along the same line of sight.

<span class="mw-page-title-main">V915 Scorpii</span> Variable star in the constellation Scorpius

V915 Scorpii is a hypergiant and semiregular variable star, located 1,718 parsecs (5,600 ly) away in the constellation Scorpius. Its apparent magnitude varies between 6.22 and 6.64, being heavily diminshed by 2.93 magnitudes due to interstellar extinction.

<span class="mw-page-title-main">TV Geminorum</span> Star in the constellation Gemini

TV Geminorum is a variable red supergiant in the constellation Gemini. Its visual magnitude varies from 6.3 to 7.5.

<span class="mw-page-title-main">6 Geminorum</span> Red supergiant star in the constellation Gemini

6 Geminorum is a variable star in the zodiac constellation of Gemini, located roughly 5,800 light years away from the Sun. It has the variable star designation BU Geminorum; 6 Geminorum is the Flamsteed designation. At its brightest this reddish hued star is barely visible to the naked eye but is readily visible with binoculars, found southeast of M 35, just to the south of WY Geminorum. It is moving further from the Earth with a heliocentric radial velocity of +27 km/s. The star is a member of the Gemini OB1 association.

References

  1. 1 2 3 4 5 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.
  2. 1 2 3 "PU Gem". Variable Star Index . Retrieved 2022-05-22.
  3. 1 2 3 Herman, R. (1973). "Classification des éTOILES B à Partir des Raises de l'HYDROGèNE-COMPARAISON avec d'Autres Classificaitons". Spectral Classification and Multicolour Photometry. 50: 17. Bibcode:1973IAUS...50...17H. doi:10.1007/978-94-010-2627-7_3. ISBN   978-94-010-2629-1.
  4. 1 2 Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  5. 1 2 3 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  6. ↑ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv: 1606.08053 . Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID   119231169.
  7. 1 2 Searle, S. C.; Prinja, R. K.; Massa, D.; Ryans, R. (2008). "Quantitative studies of the optical and UV spectra of Galactic early B supergiants. I. Fundamental parameters". Astronomy and Astrophysics. 481 (3): 777. arXiv: 0801.4289 . Bibcode:2008A&A...481..777S. doi:10.1051/0004-6361:20077125. S2CID   1552752.
  8. 1 2 3 4 5 6 Haucke, M.; et al. (June 2018). "Wind properties of variable B supergiants. Evidence of pulsations connected with mass-loss episodes". Astronomy & Astrophysics. 614: 28. arXiv: 1902.01341 . Bibcode:2018A&A...614A..91H. doi:10.1051/0004-6361/201731678. S2CID   126150688. A91.
  9. ↑ "Hipparcos Tools Interactive Data Access". Hipparcos. ESA. Retrieved 8 December 2021.
  10. ↑ Roberts, Lewis C.; Turner, Nils H.; Bradford, L. William; Ten Brummelaar, Theo A.; Oppenheimer, Ben R.; Kuhn, Jeff R.; Whitman, Kathryn; Perrin, Marshall D.; Graham, James R. (2005). "Adaptive Optics Photometry and Astrometry of Binary Stars". The Astronomical Journal. 130 (5): 2262. Bibcode:2005AJ....130.2262R. doi: 10.1086/491586 .
  11. ↑ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode:2001AJ....122.3466M. doi: 10.1086/323920 .
  12. ↑ Rosendhal, J. D. (1973). "A survey of H-alpha emission in early-type high-luminosity stars". Astrophysical Journal. 186: 909. Bibcode:1973ApJ...186..909R. doi:10.1086/152555.
  13. ↑ Kohoutek, L.; Wehmeyer, R. (1999). "Catalogue of H-alpha emission stars in the Northern Milky Way". Astronomy and Astrophysics Supplement. 134 (2): 255. Bibcode:1999A&AS..134..255K. doi: 10.1051/aas:1999101 .
  14. ↑ Skiff, B. A. (2014). "VizieR Online Data Catalog: Catalogue of Stellar Spectral Classifications (Skiff, 2009-2016)". VizieR On-line Data Catalog: B/Mk. Originally Published in: Lowell Observatory (October 2014). 1. Bibcode:2014yCat....1.2023S.
  15. ↑ Meyer, C.; Rabbia, Y.; Froeschle, M.; Helmer, G.; Amieux, G. (1995). "Observations of lunar occultations at Observatoire de la Cote d'Azur". Astronomy and Astrophysics Supplement. 110: 107. Bibcode:1995A&AS..110..107M.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.