U Vulpeculae

{{Short description|Variable star in the constellation Vulpecula}}

{{Starbox begin

| name = U Vulpeculae

}}

{{Starbox image

| image = 250px

| caption = A visual band light curve for U Vulpeculae, adapted from Kiss (1998)

}}

{{Starbox observe

| epoch = J2000.0

| constell = Vulpecula

| ra = {{RA|19|36|37.7281}}

| dec = {{DEC|20|19|58.5692}}

| appmag_v = 6.73 - 7.54

}}

{{Starbox character

| class = F6Iab-G2

| appmag_1_passband =

| appmag_1 =

| r-i =

| v-r =

| b-v =

| u-b =

| variable = δ Cep

}}

{{Starbox astrometry

| radial_v =

| prop_mo_ra = {{val|0.906|0.050}}

| prop_mo_dec = {{val|−0.960|0.062}}

| parallax = 1.0530

| p_error = 0.0390

| parallax_footnote =

| absmag_v = -3.69

}}

{{Starbox orbit

| reference =

| period_unitless = 2,510 days

| eccentricity = 0.675

| k1 = 3.64

| periastron = 2444800

| periarg = 353

}}

{{Starbox detail

| mass = 6.5

| radius = 60

| gravity = 1.75 - 1.85

| luminosity =

| temperature = 5,655 - 5,965

| metal_fe = 0.09

| rotational_velocity =

| age_myr = 82

}}

{{Starbox catalog

| names = {{odlist | BD=+20° 4200 | HD=185059 | HIP=96458 | HR=7458 | SAO=87447}}

}}

{{Starbox reference

| Simbad = U+Vulpeculae

}}

U Vulpeculae is a variable and binary star in the constellation Vulpecula. It is not visible to the naked eye, but can be seen with binoculars.

It is a classical Cepheid variable and its apparent magnitude ranges from 6.73 to 7.54 over a precise cycle of 7.99 days. Its variable nature was discovered in 1898 at Potsdam Observatory by Gustav Müller and Paul Kempf.

In 1991 a study of radial velocities showed that it U Vulpeculae is a spectroscopic binary and a full orbit with a period of 2510 days (6.9 years) was first calculated in 1996. The secondary star is invisible and is only known from its effect on the motion of the primary.

References

{{Reflist|refs=

{{cite journal |last1=Kiss |first1=Laszlo L. |title=A photometric and spectroscopic study of the brightest northern Cepheids - I. Observations |journal=Monthly Notices of the Royal Astronomical Society |date=July 1998 |volume=297 |issue=3 |page=825 |doi=10.1046/j.1365-8711.1998.01559.x |bibcode=1998MNRAS.297..825K |doi-access=free }}

{{cite web | title=U Vulpeculae | url=http://www.aavso.org/vsx/index.php?view=detail.top&oid=38179 | last=Watson | first=Christopher | date=4 January 2010 | work=AAVSO Website | publisher=American Association of Variable Star Observers | access-date=2 August 2015}}

{{cite journal | title=Cepheids and binarity. II. Radial velocities and spectroscopic orbits of four galactic Cepheids: RX Camelopardalis, MW Cygni, Z Lacertae and U Vulpeculae | language=fr | last1=Imbert | first1=M. | journal=Astronomy and Astrophysics Supplement | volume=116 | pages=497–514 | year=1996 | bibcode=1996A&AS..116..497I | doi=10.1051/aas:1996312| doi-access=free }}

{{cite journal | title=Zwei neue Veränderliche von kurzer Periode | url=https://zenodo.org/record/1424765 | language=de | last1=Müller | first1=G. | last2=Kempf | first2=P. | journal=Astronomische Nachrichten | volume=146 | issue=3 | pages=37–42 | year=1898 | bibcode=1898AN....146...37M | doi=10.1002/asna.18981460303 }}

{{cite journal | title=Northern Cepheids: Period Update and Duplicity Effects | url=http://articles.adsabs.harvard.edu/full/1991CoKon..96..123S | last1=Szabados | first1=L. | journal=Communications of the Konkoly Observatory | volume=11 part 3 | number=96 | pages=123–244 | year=1991 | bibcode=1991CoKon..96..123S }}

{{cite journal|bibcode=2009yCat....102025S|title=VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)|journal=VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S|volume=1|pages=B/gcvs|display-authors=etal|last1=Samus|first1=N. N.|last2=Durlevich|first2=O. V.|year=2009}}

{{cite journal|bibcode=2013AstL...39..851M|title=Properties of the population of classical Cepheids in the Galaxy|journal=Astronomy Letters|volume=39|issue=12|pages=851|last1=Marsakov|first1=V. A.|last2=Koval'|first2=V. V.|last3=Kovtyukh|first3=V. V.|last4=Mishenina|first4=T. V.|year=2013|doi=10.1134/s1063773713120050|s2cid=119788977}}

{{cite journal|bibcode=2013MNRAS.428.3252A|title=Barium abundances in Cepheids|journal=Monthly Notices of the Royal Astronomical Society|volume=428|issue=4|pages=3252|last1=Andrievsky|first1=S. M.|last2=Lépine|first2=J. R. D.|last3=Korotin|first3=S. A.|last4=Luck|first4=R. E.|last5=Kovtyukh|first5=V. V.|last6=MacIel|first6=W. J.|year=2013|doi=10.1093/mnras/sts270|arxiv=1210.6211|doi-access=free}}

{{cite journal|bibcode=2010MNRAS.408.1568K|title=Accurate luminosities for F-G supergiants from FeII/FeI line depth ratios|journal=Monthly Notices of the Royal Astronomical Society|volume=408|issue=3|pages=1568|last1=Kovtyukh|first1=V. V.|last2=Chekhonadskikh|first2=F. A.|last3=Luck|first3=R. E.|last4=Soubiran|first4=C.|last5=Yasinskaya|first5=M. P.|last6=Belik|first6=S. I.|year=2010|doi=10.1111/j.1365-2966.2010.17217.x|doi-access=free|url=https://hal.archives-ouvertes.fr/hal-00521973/file/mnras0408-1568.pdf}}

{{cite journal|bibcode=2008A&A...488...25G|title=Baade-Wesselink distances and the effect of metallicity in classical cepheids|journal=Astronomy and Astrophysics|volume=488|issue=1|pages=25–35|last1=Groenewegen|first1=M. A. T.|year=2008|arxiv=0807.1269|doi=10.1051/0004-6361:200809859|s2cid=13871801}}

}}

Category:Vulpecula

Category:Classical Cepheid variables

Vulpeculae, U

Category:F-type supergiants

Category:G-type supergiants

Category:Durchmusterung objects

7458

185059

096458

Category:Spectroscopic binaries