sigma Persei

{{Short description|Star in the constellation Perseus}}

{{Starbox begin

| name = σ Persei

}}

{{Starbox image

|image=

{{Location mark

|image=Perseus constellation map.svg|alt=|float=center|width=280

|label=|position=right

|mark=Red circle.svg|mark_width=10|mark_link=Sigma Persei

|x=521|y=471

}}

|caption=Location of σ Persei (circled)

}}

{{Starbox observe

| epoch = J2000

| constell = Perseus

| ra = {{RA|03|30|34.48537}}

| dec = {{DEC|+47|59|42.7789}}

| appmag_v = 4.36{{cite journal |bibcode=2002yCat.2237....0D |title=VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system |journal=CDS/ADC Collection of Electronic Catalogues |volume=2237 |last1=Ducati |first1=J. R. |year=2002 }}

}}

{{Starbox character

| type = horizontal branch

| class = K3III{{cite journal | bibcode=1995yCat.5050....0H | title=VizieR Online Data Catalog: Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991) | journal=VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H | volume=5050 | last1=Hoffleit | first1=D. | last2=Warren | first2=W. H. | year=1995 }}

| b-v = +1.35

| u-b = +1.54

}}

{{Starbox astrometry

| radial_v = {{val|+14.32|0.15}}

| prop_mo_ra = +3.954

| prop_mo_dec = +18.968

| pm_footnote =

| parallax = 9.5060

| p_error = 0.2003

| parallax_footnote =

| absmag_v = −0.85{{cite journal | bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015 | arxiv=1108.4971 | title=XHIP: An extended hipparcos compilation | journal=Astronomy Letters | volume=38 | issue=5 | pages=331 | year=2012 | last1=Anderson | first1=E. | last2=Francis | first2=Ch. | s2cid=119257644 }} [http://vizier.u-strasbg.fr/viz-bin/VizieR-4?-source=V/137D/XHIP&HIP=16335 Vizier catalog entry]

}}

{{Starbox detail

| mass = 1.32{{cite journal | arxiv=1412.4634 | bibcode=2015A&A...574A.116R | doi=10.1051/0004-6361/201322360 | title=Precise radial velocities of giant stars | journal=Astronomy & Astrophysics | volume=574 | pages=A116 | year=2015 | last1=Reffert | first1=Sabine | last2=Bergmann | first2=Christoph | last3=Quirrenbach | first3=Andreas | last4=Trifonov | first4=Trifon | last5=Künstler | first5=Andreas | hdl=10722/215277 | s2cid=59334290 }} [http://vizier.u-strasbg.fr/viz-bin/VizieR-4?-source=J/A%2bA/574/A116&HIP=16335 Vizier catalog entry]

| radius = 36.89

| temperature = 4,165

| luminosity = 368

| rotational_velocity = 2.2{{cite journal |bibcode=2007A&A...475.1003H |title=Precise radial velocities of giant stars. III. Spectroscopic stellar parameters |last1=Hekker |first1=S. |last2=Meléndez |first2=J. |journal=Astronomy and Astrophysics |date=2007 |volume=475 |issue=3 |page=1003 |doi=10.1051/0004-6361:20078233 |arxiv=0709.1145 }}

| gravity = 1.46

| metal_fe = −0.20

| age_hyr = 6.6

}}

{{Starbox catalog

| names = {{odlist | B=σ Per | F=35 Per | BD=+47 843 | FK5=124 | GC=4158 | HD=21552 | HIP=16335 | HR=1052 | NSV=1167 | PPM=46257 | SAO=38890}}

}}

{{Starbox reference

| Simbad = Sigma+Persei

}}

{{Starbox end}}

Image:Sigma Persei.jpg

Sigma Persei (Sigma Per, σ Persei, σ Per) is an orange K-type giant star with an apparent magnitude of +4.36. It is approximately 343 light-years from Earth.

Sigma Persei is moving through the Galaxy at a speed of 17.4 km/s relative to the Sun. Its projected Galactic orbit carries it between 24,400 and 43,600 light years from the center of the Galaxy. It came closest to the Sun 5.1 million years ago when it had brightened to magnitude 3.11 from a distance of 202 light years.[https://web.archive.org/web/20140330041910/http://www.astrostudio.org/xhip.php?hip=16335 Sigma Persei (HIP 16335)]

In 2014 a planet was reported, Sigma Persei b, with a period of 580 days and a mass approximately 6.5 times that of Jupiter.{{cite journal | bibcode=2014JKAS...47...69L | doi=10.5303/JKAS.2014.47.2.69 | arxiv=1405.2130| title=PLANETARY COMPANION IN K GIANT σ PERSEI | journal=Journal of the Korean Astronomical Society | volume=47 | issue=2 | pages=69 | year=2014 | last1=Lee | first1=Byeong-Cheol | last2=Han | first2=Inwoo | last3=Park | first3=Myeong-Gu | last4=Mkrtichian | first4=David E. | last5=Jeong | first5=Gwanghui | last6=Kim | first6=Kang-Min | last7=Valyavin | first7=Gennady }} However, a 2025 study found that the observed radial velocity variations are intrinsic to the star, and not caused by a planetary companion.