Nu Cephei

Quality 0.50 · 1 view · Updated 2 months ago

Star in the constellation Cepheus

title: "Nu Cephei" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["a-type-supergiants", "alpha-cygni-variables", "cepheus-(constellation)", "bayer-objects", "bright-star-catalogue-objects", "durchmusterung-objects", "flamsteed-objects", "henry-draper-catalogue-objects", "hipparcos-objects"] description: "Star in the constellation Cepheus" topic_path: "general/a-type-supergiants" source: "https://en.wikipedia.org/wiki/Nu_Cephei" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Star in the constellation Cepheus ::

| name = ν Cephei | image = |image=Cepheus constellation map.svg|alt=|float=center|width=240 |label=|position=right |mark=Red circle.svg|mark_width=10|mark_link=ν Cep |x=744|y=954 | caption = Location of ν Cephei (circled in red) | epoch = J2000.0 | constell = Cepheus | ra = | dec = | appmag_v = 4.289 () | class = A2Iab | appmag_1_passband = U | appmag_1 = 4.94 | appmag_2_passband = B | appmag_2 = 4.81 | appmag_3_passband = J | appmag_3 = 3.14 | appmag_4_passband = K | appmag_4 = 2.85 | b-v = +0.518 | u-b = +0.119 | variable = Alpha Cygni | type = Blue supergiant | radial_v = −25.90 | prop_mo_ra = −3.545 | prop_mo_dec = −2.025 | pm_footnote = | parallax = 0.9321 | p_error = 0.0865 | parallax_footnote = | dist_pc = 1,450

| absmag_v = −6.82 | source = | mass = 15.4 | radius = 137 | gravity = 1.35 | luminosity = 102,000 | temperature = 8,800 | metal_fe = | rotation = | rotational_velocity = 15 | age_myr = 8 | names = | Simbad = HD+207260 | ARICNS =

Nu Cephei is a blue-hued variable star in the northern constellation Cepheus. Its name is a Bayer designation that is Latinized from ν Cephei, and abbreviated Nu Cep or ν Cep. This is a pulsating α Cygni variable star that ranges in apparent visual magnitude from . This is bright enough to make it visible to the naked eye as a fourth-magnitude star. Distance estimates place it at about 3,500 light-years from Earth. It is drifting closer to the Sun with a line of sight velocity component of −26 km/s.

ν Cephei is a member of the Cepheus OB2 stellar association, which includes stars such as μ Cephei and VV Cephei.

Properties

::figure[src="https://upload.wikimedia.org/wikipedia/commons/8/87/NuCepLightCurve.png" caption="TESS]]'' data,"] ::

The stellar classification of this star is A2Iab, matching an evolved blue supergiant. It began life as an approximately main sequence star around eight million years ago. Nu Cephei has exhausted its core hydrogen and expanded and cooled into a supergiant. Elemental abundance analyses indicate that it has not yet spent time as a red supergiant, which would have brought about convection of fusion products to the surface in a dredge-up.

ν Cephei is currently about 15 times as massive as the sun, 137 times as large, and 100,000 times as luminous. Its large size and luminosity cause it to be somewhat unstable and produce irregular pulsations. This is a common feature of class A and B supergiants, which are grouped as α Cygni variable stars. Variability was first reported by Helmut Abt in 1957. The brightness changes by at most a tenth of a magnitude. A variety of values for the variability period have been published, including 5 to 10 days, 7.6 days and 90 days.

References

| title=MAST: Barbara A. Mikulski Archive for Space Telescopes | url=https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html | publisher=Space Telescope Science Institute | access-date=27 September 2024}}

--

| title=Understanding A-type supergiants. II. Atmospheric parameters and rotational velocities of Galactic A-type supergiants | display-authors=1 | last1=Verdugo | first1=E. | last2=Talavera | first2=A. | last3=Gómez De Castro | first3=A. I. | journal=Astronomy and Astrophysics | volume=346 | pages=819 | year=1999 | bibcode=1999A&A...346..819V }}

References

  1. "nu. Cep".
  2. {{Cite Gaia DR3. 2203889767044993920
  3. Abt, Helmut A.. (July 1957). "The Variability of Supergiants". Astrophysical Journal.
  4. (August 1983). "Photometric variability of B- and A-type supergiants". Publications of the Astronomical Society of the Pacific.
  5. Buscombe, W.. (June 1974). "Variations in the spectra of A-type supergiants". The Observatory.
  6. "nu. Cep". AAVSO.
  7. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics.
  8. (2012). "Quantitative spectroscopy of Galactic BA-type supergiants. I. Atmospheric parameters". Astronomy & Astrophysics.
  9. (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.
  10. Ducati, J. R.. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues.
  11. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters.
  12. Yüce, Kutluay. (2005). "Spectral Analysis of 4 Lacertae and ν Cephei". Baltic Astronomy.
  13. Firnstein, Markus. (2010). "Quantitative Spectroscopy of Galactic BA-Type Supergiants". Erlangen, Nürnberg, Univ.
  14. Humphreys, R. M.. (1978). "Studies of luminous stars in nearby galaxies. I. Supergiants and O stars in the Milky Way". Astrophysical Journal.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::

a-type-supergiantsalpha-cygni-variablescepheus-(constellation)bayer-objectsbright-star-catalogue-objectsdurchmusterung-objectsflamsteed-objectshenry-draper-catalogue-objectshipparcos-objects