theta1 Microscopii

{{For|other stars with the name θ Microscopii|Theta Microscopii}}

{{Starbox image

| image =

{{Location mark

|image=Microscopium constellation map.svg|alt=|float=center|width=240

|label=|position=right

|mark=Red circle.svg|mark_width=10|mark_link=Theta¹ Microscopii

|x=380|y=836

}}

| caption = Location of θ¹ Microscopii (circled)

}}

{{Starbox observe

| epoch = J2000

| constell = Microscopium

| ra = {{RA|21|20|45.62633}}

| dec = {{DEC|-40|48|34.3607}}

| appmag_v = 4.82

}}

{{Starbox character

| type =

| class = A7VpSrCrEu

| b-v = +0.02

| u-b = -0.07

| variable = α² CVn

}}

{{Starbox astrometry

| radial_v = +2.30

| prop_mo_ra = +75.480

| prop_mo_dec = +8.657

| parallax = 18.2678

| p_error = 0.5314

| parallax_footnote =

| absmag_v = 1.03

}}

{{Starbox detail

| source =

| mass = {{Val|2.32|0.18|0.26}}

| radius = {{Val|2.35|0.34}}

| temperature = {{Val|9240|480|fmt=commas}}

| luminosity = {{Val|36.3|8.4|6.8}}

| rotational_velocity = {{Val|43.7|1.7}}

| gravity = {{Val|4.06|0.12}}

| metal_fe = 0.00

| age_myr = {{Val|437|209}}

}}

{{Starbox catalog

| names = {{odlist | B=θ¹ Mic | CD=-41°14475 | FK5=802 | HD=203006 | HIP=105382 | HR=8151 | SAO=230644 | GC=29854 | WDS=J21208-4049 }}

}}

{{Starbox reference

| Simbad = Theta1+Microscopii

}}

θ¹ Microscopii, Latinized as Theta¹ Microscopii, is a suspected binary star system in the southern constellation of Microscopium. It is visible to the naked eye was a faint, white-hued point of light with an apparent visual magnitude of 4.82. The distance to this system is approximately 179 light years based on parallax.

File:Theta1MicLightCurve.png for Theta¹ Microscopii, plotted from TESS data]]

The primary is an α² CVn variable with a period of 2.125 days and a magnitude ranging from 4.77 to 4.87, as well as an Ap star, a chemically peculiar star with strong metallic lines in its spectrum. It is an A-type main-sequence star with a stellar classification of A7VpSrCrEu, where the suffix notation indicates abundance anomalies of strontium, chromium, and europium. The star is 437 million years old with 2.3 times the mass of the Sun and 2.4 times the Sun's radius. It is radiating 36 times the luminosity of the Sun from its photosphere at an effective temperature of 9,240 K.

Its companion is a magnitude 7.42 star at an angular separation of {{Val|0.10|ul=arcsecond}} from the primary along a position angle of 46°, as of 2018.

References

{{reflist|refs=

{{cite web

| 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=8 December 2021}}

{{cite simbad

| title=tet01 Mic | accessdate=2019-09-03 | postscript=. }}

{{cite conference

| last1=Watson| first1=C. L.

| title=The International Variable Star Index (VSX)

| conference=The Society for Astronomical Sciences 25th Annual Symposium on Telescope Science. Held May 23–25

| volume=25 | pages=47 | year=2006

| bibcode=2006SASS...25...47W }}

{{cite journal

| last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.

| title=A catalogue of multiplicity among bright stellar systems

| journal=Monthly Notices of the Royal Astronomical Society

| volume=389 | issue=2 | pages=869–879 | date=September 2008

| bibcode=2008MNRAS.389..869E | arxiv=0806.2878

| doi=10.1111/j.1365-2966.2008.13596.x | doi-access=free | s2cid=14878976 }}

{{cite journal | display-authors=1

| title=A Volume-Limited Survey of mCP Stars Within 100pc I: Fundamental Parameters and Chemical Abundances

| last1=Sikora | first1=J. | last2=Wade | first2=G. A.

| last3=Power | first3=J. | last4=Neiner | first4=C.

| journal=Monthly Notices of the Royal Astronomical Society

| volume=483 | issue=2 | pages=2300–2324 | date=February 2019

| arxiv=1811.05633 | doi=10.1093/mnras/sty3105

| doi-access=free

| bibcode=2019MNRAS.483.2300S | s2cid=119089236

}}

{{cite journal

| display-authors=1 | last1=Mason | first1=B. D.

| last2=Wycoff | first2=G. L. | last3=Hartkopf | first3=W. I.

| last4=Douglass | first4=G. G. | last5=Worley | first5=C. E.

| title=The Washington Visual Double Star Catalog

| doi=10.1086/323920 | s2cid=119533755 | doi-access=free }}

{{cite journal

| last1=Ducati | first1=J. R.

| title=VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system

| journal=CDS/ADC Collection of Electronic Catalogues

| volume=2237 | year=2002 | bibcode=2002yCat.2237....0D }}

{{cite journal

| last1=Abt | first1=Helmut A. | last2=Morrell | first2=Nidia I.

| title=The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars

| journal=Astrophysical Journal Supplement

| volume=99 | pages=135 | year=1995

| doi=10.1086/192182 | bibcode=1995ApJS...99..135A | doi-access=free }}

{{cite journal

| last=Wilson | first=R. E. | year=1953

| title=General Catalogue of Stellar Radial Velocities

| journal=Carnegie Institute Washington D.C. Publication | publisher=Carnegie Institution of Washington

| bibcode=1953GCRV..C......0W | isbn=9780598216885 | lccn=54001336 }}

{{cite journal

| last1=Anderson | first1=E. | last2=Francis | first2=Ch.

| title=XHIP: An extended hipparcos compilation

| journal=Astronomy Letters

| volume=38 | issue=5 | pages=331 | year=2012

| bibcode=2012AstL...38..331A | arxiv=1108.4971

| doi=10.1134/S1063773712050015

| s2cid=119257644 }} [http://vizier.u-strasbg.fr/viz-bin/VizieR-4?-source=V/137D/XHIP&HIP=105382 Vizier catalog entry]

{{cite journal

| doi=10.1134/S1063773712120031

| title=Dependence of kinematics on the age of stars in the solar neighborhood

| journal=Astronomy Letters

| volume=38 | issue=12 | pages=771–782 | year=2012

| last1=Gontcharov | first1=G. A.

| bibcode=2012AstL...38..771G | arxiv=1606.08814

| s2cid=118345778

}} [http://vizier.u-strasbg.fr/viz-bin/VizieR-4?-source=J/PAZh/38/860/thin&HIP=105382 Vizier catalog entry]

}}

Category:A-type main-sequence stars

Category:Ap stars

Category:Microscopium

Category:Alpha2 Canum Venaticorum variables