eta Scuti

{{short description|Star in the constellation Scutum}}

{{Starbox begin

| name = η Scuti

}}

{{Starbox image

|image=

{{Location mark

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

|label=|position=right

|mark=Red circle.svg|mark_width=10|mark_link=Eta Scuti

|x=300|y=260

}}

|caption=Location of η Scuti (circled)

}}

{{Starbox observe

| epoch = J2000

| constell = Scutum

| ra = {{RA|18|57|03.67027}}{{cite DR2|4253892913176211200}}

| dec = {{DEC|−05|50|46.7305}}

| appmag_v = 4.83{{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=93026 Vizier catalog entry]

}}

{{Starbox character

| type = horizontal branch

| class = K1-III{{cite journal | bibcode=1989ApJS...71..245K | doi=10.1086/191373| title=The Perkins catalog of revised MK types for the cooler stars| journal=The Astrophysical Journal Supplement Series| volume=71| pages=245| year=1989| last1=Keenan| first1=Philip C.| last2=McNeil| first2=Raymond C.}}

| b-v = +1.08{{cite journal | bibcode=2014JAVSO..42..443M | title=Sloan Magnitudes for the Brightest Stars | journal=The Journal of the American Association of Variable Star Observers | volume=42 | issue=2 | pages=443 | last1=Mallama | first1=A. | year=2014 }}[http://vizier.u-strasbg.fr/viz-bin/VizieR-4?-source=J/other/JAVSO/42.443/ugriz&HD=175751 Vizier catalog entry]

| u-b = +1.02

}}

{{Starbox astrometry

| radial_v = {{Val|−92.22|0.16}}

| prop_mo_ra = +61.545

| prop_mo_dec = −41.429

| parallax = 15.2960

| p_error = 0.1740

| parallax_footnote =

| absmag_v = 0.87

}}

{{Starbox detail

| mass = 1.50{{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=93026 Vizier catalog entry]

| radius = {{Val|11.97|0.18|0.13}}

| temperature = {{Val|4693|27|266|fmt=commas}}

| luminosity = {{Val|62.7|0.8}}

| rotational_velocity = < 1.0{{cite journal | bibcode=2014A&A...561A.126D | doi=10.1051/0004-6361/201220762 | arxiv=1312.3474 | title=A catalog of rotational and radial velocities for evolved stars | journal=Astronomy & Astrophysics | volume=561 | pages=A126 | year=2014 | last1=De Medeiros | first1=J. R. | last2=Alves | first2=S. | last3=Udry | first3=S. | last4=Andersen | first4=J. | last5=Nordström | first5=B. | last6=Mayor | first6=M. | s2cid=54046583 }} [http://vizier.u-strasbg.fr/viz-bin/VizieR-4?-source=J/A%2bA/561/A126/table1&HD=175751 Vizier catalog entry]

| gravity = 2.54

| metal_fe = −0.03

| age_gyr = 2.8

}}

{{Starbox catalog

| names = {{odlist | B=η Sct | BD=-06°4976 | FK5=3821 | HD=175751 | HIP=93026 | HR=7149 | SAO=142838 | GC=26013 | GSC=05127-07358 }}{{cite simbad | title=eta Sct | accessdate=2019-08-23 }}

}}

{{Starbox reference

| Simbad = Eta+Scuti

}}

{{Starbox end}}

Eta Scuti, Latinized from η Scuti, is a single star in the southern constellation of Scutum, near the constellation border with Aquila. Eta Scuti was a latter designation of 9 Aquilae before the official constellation borders were set in 1922. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of +4.83. This object is located approximately 213 light-years from the Sun based on parallax, and is moving closer with a radial velocity of −92 km/s.

This is an aging giant star with a stellar classification of K1-III. After exhausting the supply of hydrogen at its core, the star cooled and expanded until currently it has 12 times the girth of the Sun. It is a red clump giant, which indicates it is presently on the horizontal branch and is generating energy through core helium fusion. The star is about 2.8 billion years old with 1.5 times the mass of the Sun. It is radiating 63 times the Sun's luminosity from its swollen photosphere at an effective temperature of {{val|4693|ul=K|fmt=commas}}.