Sigma1 Cancri
A-type main sequence star in the constellation Cancer
title: "Sigma1 Cancri" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["a-type-main-sequence-stars", "ap-stars", "binary-stars", "cancer-(constellation)", "bayer-objects", "bright-star-catalogue-objects", "durchmusterung-objects", "flamsteed-objects", "henry-draper-catalogue-objects", "hipparcos-objects"] description: "A-type main sequence star in the constellation Cancer" topic_path: "science/astronomy" source: "https://en.wikipedia.org/wiki/Sigma1_Cancri" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0
::summary A-type main sequence star in the constellation Cancer ::
| name = Sigma1 Cancri | epoch = J2000.0 | equinox = J2000.0 (ICRS) | constell = Cancer | ra = | dec = | appmag_v = 5.68 + 13.3 | type = main sequence | class = A8 Vas | b-v = +0.20 | u-b = +0.08 | r-i = | variable = Constant | radial_v = | prop_mo_ra = −5.598 | prop_mo_dec = +15.832 | pm_footnote = | parallax = 14.7289 | p_error = 0.0959 | parallax_footnote = | absmag_v = +1.62 | component1 = σ1 Cnc A | mass = 1.84 | radius = 2.32 | luminosity = 17.7 | temperature = 7,780 | gravity = 3.97 | metal_fe = | rotational_velocity = 84 | age_myr = 301 | component2 = σ1 Cnc B | mass2 = 0.62 | names = | Simbad = 51+Cnc Sigma1 Cancri is a binary star system in the zodiac constellation of Cancer. Its name is a Bayer designation that is Latinized from σ1 Cancri, and abbreviated Sigma1 Cnc or σ1 Cnc. The primary component is faintly visible to the naked eye, with an apparent visual magnitude of +5.68. Based upon an annual parallax shift of as seen from Earth, this star is located around 221 ly from the Sun. It is moving further away with a line of sight velocity of −11 km/s.
This is a chemically peculiar A-type main sequence star with a stellar classification of A8 Vas. At an age of about 301 million years, Sigma1 Cancri is around 67% of the way through its main sequence lifespan. The star has 1.8 times the mass of the Sun and is radiating 18 times the Sun's luminosity from its photosphere at an effective temperature of .
There is a magnitude 13.3 companion at an angular separation of 5.2 arc seconds along a position angle of 276°, as of 2011. At that distance, the pair have a projected separation of 333.2 AU. This star, designated Sigma1 Cancri B, has an estimated 62% of the mass of the Sun.
References
| display-authors=1 | last1=Mason | first1=B. D. | last2=Wycoff | first2=G. L. | last3=Hartkopf | first3=W. I. | last4=Douglass | first4=G. G. | last5=Worley | first5=C. E. | title=The Washington Visual Double Star Catalog | journal=The Astronomical Journal | postscript=. | year=2014 | volume=122 | issue=6 | pages=3466–3471 | bibcode=2001AJ....122.3466M | doi=10.1086/323920 | doi-access=free }}
| title=Spectral Classification of a and F Stars | last=Barry | first=Don C. | postscript=. | journal=Astrophysical Journal Supplement | volume=19 | page=281 | date=January 1970 | doi=10.1086/190209 | bibcode=1970ApJS...19..281B }}
| last1=Zorec | first1=J. | last2=Royer | first2=F. | title=Rotational velocities of A-type stars. IV. Evolution of rotational velocities | journal=Astronomy & Astrophysics | volume=537 | page=A120 | date=January 2012 | doi=10.1051/0004-6361/201117691 | bibcode=2012A&A...537A.120Z | arxiv=1201.2052 | s2cid=55586789 | postscript=. }}
| title=The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets | last1=David | first1=Trevor J. | last2=Hillenbrand | first2=Lynne A. | journal=The Astrophysical Journal | volume=804 | issue=2 | pages=146 | year=2015 | bibcode=2015ApJ...804..146D | doi=10.1088/0004-637X/804/2/146 | arxiv=1501.03154 | s2cid=33401607 | postscript=. }}
| last1=Guetter | first1=H. H. | last2=Hewitt | first2=A. V. | title=Photoelectric UBV photometry for 317 PZT and VZT stars | journal=Astronomical Society of the Pacific | volume=96 | pages=441–443 | date=1984 | postscript=. | bibcode=1984PASP...96..441G | doi=10.1086/131362 | doi-access=free }}
| title=* sig01 Cnc | mode=cs2 | accessdate=2017-06-13 | postscript=. }}
| title=Gaia Data Release 3 (Gaia DR3). Part 1. Main source | author=Gaia Collaboration | date=May 2022 | work=VizieR On-line Data Catalog: I/355. Originally published in: doi:10.1051/0004-63 | doi=10.26093/cds/vizier.1355 | bibcode=2022yCat.1355....0G }}
| title=The VAST Survey - III. The multiplicity of A-type stars within 75 pc | last1=De Rosa |first1=R. J. |last2=Patience |first2=J. | last3=Wilson |first3=P. A. |last4=Schneider |first4=A. | last5=Wiktorowicz |first5=S. J. |last6=Vigan |first6=A. | last7=Marois |first7=C. |last8=Song |first8=I. | last9=MacIntosh |first9=B. |last10=Graham |first10=J. R. | last11=Doyon |first11=R. |last12=Bessell |first12=M. S. | last13=Thomas |first13=S. |last14=Lai |first14=O. |year=2014 | journal=Monthly Notices of the Royal Astronomical Society | volume=437 | issue=2 | pages=1216 | display-authors=1 | bibcode=2014MNRAS.437.1216D | arxiv=1311.7141 | doi=10.1093/mnras/stt1932 | doi-access=free | s2cid=88503488 }}
References
- {{Cite Gaia DR3. 712988829111292672
- {{Cite XHIP. 43584
- (2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal.
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