Epsilon Andromedae

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

{{Starbox begin

| name = ε Andromedae}}

{{Starbox image

| image= {{Location mark

|image=Andromeda constellation map.svg|alt=|float=center|width=260

|label=|position=right

|mark=Red circle.svg|mark_width=10|mark_link=ζ And

|x=632|y=742

}}

| caption=Location of ε Andromedae (circled) }}

{{Starbox observe

| epoch = J2000.0

| equinox = J2000.0 (ICRS)

| constell = Andromeda

| ra = {{RA|00|38|33.347}}{{Cite Gaia EDR3|2858181236614036864}}

| dec = {{DEC|+29|18|42.31}}

| appmag_v = 4.357{{cite journal | last1=Jennens | first1=P. A. | last2=Helfer | first2=H. L. | title=A new photometric metal abundance and luminosity calibration for field G and K giants. | journal=Monthly Notices of the Royal Astronomical Society | volume=172 | pages=667–679 |date=September 1975 | issue=3 | bibcode=1975MNRAS.172..667J | doi = 10.1093/mnras/172.3.667 | doi-access=free }}

}}

{{Starbox character

| type = red clump

| class = {{nowrap|G6 III Fe−3 CH1}}{{cite journal | title=The Perkins catalog of revised MK types for the cooler stars | journal=Astrophysical Journal Supplement Series | volume=71 | pages=245 | year=1989 | last1=Keenan | first1=Philip C. | last2=McNeil | first2=Raymond C. | bibcode=1989ApJS...71..245K | doi=10.1086/191373 }}

| u-b = +0.463

| b-v = +0.8713

| v-r = +0.6

| r-i = +0.51[http://webviz.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=V/50/catalog&recno=163 HR 163], database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID [http://vizier.u-strasbg.fr/viz-bin/Cat?V/50 V/50]. Accessed on line August 28, 2008.

}}

{{Starbox astrometry

| radial_v = {{Val|−84.43|0.15}}

| prop_mo_ra = −228.701

| prop_mo_dec = −253.206

| pm_footnote =

| parallax = 19.2451

| p_error = 0.1188

| parallax_footnote =

| absmag_v = +0.69{{cite journal | display-authors=1 | last1=Takeda | first1=Yoichi | last2=Sato | first2=Bun'ei | last3=Murata | first3=Daisuke | title=Stellar Parameters and Elemental Abundances of Late-G Giants | journal=Publications of the Astronomical Society of Japan | date=August 2008 | volume=60 | issue=4 | pages=781–802 | bibcode=2008PASJ...60..781T | arxiv=0805.2434 | doi=10.1093/pasj/60.4.781 | s2cid=16258166 }}

}}

{{Starbox detail

| source={{cite journal | title=Stellar parameters and chemical abundances of 223 evolved stars with and without planets | journal=Astronomy & Astrophysics | volume=574 | pages=A50 | year=2015 | last1=Jofré | first1=E. | last2=Petrucci | first2=R. | last3=Saffe | first3=C. | last4=Saker | first4=L. | last5=de la Villarmois | first5=E. Artur | last6=Chavero | first6=C. | last7=Gómez | first7=M. | last8=Mauas | first8=P. J. D. | bibcode=2015A&A...574A..50J | doi=10.1051/0004-6361/201424474 | arxiv=1410.6422 | s2cid=53666931 }}

| rotational_velocity = {{Val|1.70|0.45}}

| radius ={{Val|9.04|0.34}}

| mass = {{Val|1.01|0.35}}

| metal_fe = {{Val|−0.53|0.05}}

| gravity = {{Val|2.88|0.02}}

| temperature = {{Val|5082|20|fmt=commas}}

| luminosity = 51.3

| age_gyr = {{Val|5.71|5.29}}

}}

{{Starbox catalog

| names = {{odlist | B=ε And, eps And | F=30 Andromedae | BD=+28°103 | FK5=19 | HD=3546 | HIP=3031 | HR=163 | SAO=74164 | GC=759 | LTT=10215 | NLTT=2065 | PPM=90002 }}{{cite simbad|title=eps And|access-date=August 28, 2008}}

}}

{{Starbox reference

| Simbad=eps+and}}

{{Starbox end}}

Epsilon Andromedae is a star in the constellation of Andromeda. Its identifier is a Bayer designation that is Latinized from ε Andromedae, and abbreviated eps And or ε And, respectively. This star can be seen with the naked eye, having an apparent visual magnitude of 4.4. Based upon an annual parallax shift of 19.2 mas as seen from Earth, it is located approximately 169 light years from the Sun. The system is moving closer to the Sun with a radial velocity of −84 km/s. Its orbit in the Milky Way is highly eccentric, causing it to move rapidly relative to the Sun and its neighboring stars.

This is an evolved G-type giant star with a stellar classification of {{nowrap|G6 III Fe−3 CH1}}. The suffix notation indicates there is a strong underabundance of iron in the spectrum, and an overabundance of cyanogen (CN). ε Andromedae is believed to be a red clump star which is fusing helium in its core. It has about the same mass as the Sun, but has expanded to nine times the Sun's radius. The star is radiating 51 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 5,082 K.