101 Virginis

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

{{Starbox begin}}

{{Starbox image

| image=

{{Location mark

|image=Virgo constellation map.svg|alt=|float=center|width=320

|label=|position=right

|mark=Red circle.svg|mark_width=8|mark_link=CY Boo

|x=80|y=110

}}

|caption=Location of CY Boötis (circled)

}}

{{Starbox observe

| epoch=J2000

| constell=Boötes

| ra={{RA|14|17|28.4519}}

{{cite journal

|last1=Van Leeuwen |first1=F.

|year=2007

|title=Validation of the new Hipparcos reduction

|journal=Astronomy and Astrophysics

|volume=474 |issue=2 |pages=653–664

|arxiv=0708.1752

|bibcode=2007A&A...474..653V

|doi=10.1051/0004-6361:20078357

|s2cid=18759600

}}

| dec={{DEC|+15|15|48.167}}

| appmag_v=5.74 - 5.90

}}

{{Starbox character

| type=AGB

| class=M3IIIa

| r-i =

| v-i = 1.98

| b-v = 1.678

| u-b =

| variable=SRb

}}

{{Starbox astrometry

| radial_v=−11.30

{{cite journal

|last1=Famaey |first1=B.

|last2=Pourbaix |first2=D.

|last3=Frankowski |first3=A.

|last4=Van Eck |first4=S.

|last5=Mayor |first5=M.

|last6=Udry |first6=S.

|last7=Jorissen |first7=A.

|year=2009

|title=Spectroscopic binaries among Hipparcos M giants,. I. Data, orbits, and intrinsic variations

|journal=Astronomy and Astrophysics

|volume=498 |issue=2 |page=627

|arxiv=0901.0934

|bibcode=2009A&A...498..627F

|doi=10.1051/0004-6361/200810698

|s2cid=18739721

}}

| prop_mo_ra=14.27

| prop_mo_dec=8.80

| parallax=3.3735

| p_error=0.1766

| parallax_footnote={{cite DR2|1231881287184934272}}

| absmag_v=−0.98{{cite XHIP|69829}}

}}

{{Starbox detail

| mass=1.2{{cite journal |bibcode=2024A&A...691A..98K |title=Transferring spectroscopic stellar labels to 217 million Gaia DR3 XP stars with SHBoost |last1=Khalatyan |first1=A. |last2=Anders |first2=F. |last3=Chiappini |first3=C. |last4=Queiroz |first4=A. B. A. |last5=Nepal |first5=S. |last6=Dal Ponte |first6=M. |last7=Jordi |first7=C. |last8=Guiglion |first8=G. |last9=Valentini |first9=M. |last10=Torralba Elipe |first10=G. |last11=Steinmetz |first11=M. |last12=Pantaleoni-González |first12=M. |last13=Malhotra |first13=S. |last14=Jiménez-Arranz |first14=Ó. |last15=Enke |first15=H. |last16=Casamiquela |first16=L. |last17=Ardèvol |first17=J. |journal=Astronomy and Astrophysics |date=2024 |volume=691 |pages=A98 |doi=10.1051/0004-6361/202451427 |arxiv=2407.06963 }}

| radius=76.78

| luminosity=1,078{{cite journal|bibcode=2012MNRAS.427..343M|title=Fundamental parameters and infrared excesses of Hipparcos stars|journal=Monthly Notices of the Royal Astronomical Society|volume=427|pages=343–357|last1=McDonald|first1=I.|last2=Zijlstra|first2=A. A.|last3=Boyer|first3=M. L.|year=2012|issue=1|doi=10.1111/j.1365-2966.2012.21873.x|doi-access=free |arxiv = 1208.2037 |s2cid=118665352}}

| temperature=3,682

| metal=−0.31

| gravity=1.35

| rotation=

| age=

}}

{{Starbox catalog

| names={{odlist | V=CY Boötis | NSV=6613 | F=101 Vir | BD=+15°2690 | HD=125180 | HIP=69829 | HR=5352 | SAO=100956 | GC=19284 | IRAS=14150+1529 | AG=+15°1445 | GSC=01469-01456 | 2MASS=J14172843+1515478 | TYC=1469-1456-1 | UBV=20098 | PPM=130465 | GCRV=8358 }}

}}

{{Starbox reference

| Simbad=HD+125180

| ARICNS =

}}{{starbox sources|HIP|HR}}

{{Starbox end}}

101 Virginis is a red giant variable star in the Boötes constellation, currently on the asymptotic giant branch.{{cite journal

| title=Asymptotic giant branch stars near the sun

| journal=The Astronomical Journal

| volume=104 | pages=275 | year=1992

| last1=Eggen | first1=Olin J.

| doi=10.1086/116239

| bibcode=1992AJ....104..275E

}}

Its apparent magnitude ranges from 5.74 to 5.9, making it faintly visible to the naked eye under good observing conditions. It was originally catalogued as 101 Virginis by Flamsteed due to an error in the position.

{{cite journal

|last1=Davies |first1=H. S.

|year=1905

|title=Flamsteed and Piazzi Identities

|url=https://archive.org/details/sim_popular-astronomy_1905-10_13_8/page/423 |journal=Popular Astronomy

|volume=13 |page=423

|bibcode=1905PA.....13..423D

}}

{{cite journal

|last1=Wagman |first1=M.

|year=1987

|title=Flamsteed's Missing Stars

|journal=Journal for the History of Astronomy

|volume=18 |issue=3

|page=209

|bibcode=1987JHA....18..209W

|doi=10.1177/002182868701800305

|s2cid=118445625

}} John R. Percy found it to be "marginally variable" in 1993. When it was confirmed as a variable star, it was actually within the border of the constellation Boötes and given the name CY Boötis.

The variability is not strongly defined but a primary period of 23 days and a secondary period of 340 days have been reported.

{{cite journal

|last1=Percy|first1=J. R.

|last2=Dunlop|first2=H.

|last3=Kassim|first3=L.

|last4=Thompson|first4=R. R.

|year=2001

|title=Periods of 25 Pulsating Red Giants

|journal=Information Bulletin on Variable Stars

|volume=5041 |page=1

|bibcode=2001IBVS.5041....1P

}}

CY Boo is listed in the Hipparcos catalogue as a "problem binary", a star which was suspected of being multiple but for which the Hipparcos observations did not give a satisfactory solution. Further observations have always shown it to be single.{{cite journal|bibcode=1999AJ....117.1890M |title=Speckle Interferometry of New and Problem HIPPARCOS Binaries |journal=The Astronomical Journal |volume=117 |issue=4 |pages=1890 |last1=Mason |first1=Brian D. |last2=Martin |first2=Christian |last3=Hartkopf |first3=William I. |last4=Barry |first4=Donald J. |last5=Germain |first5=Marvin E. |last6=Douglass |first6=Geoffrey G. |last7=Worley |first7=Charles E. |last8=Wycoff |first8=Gary L. |last9=Ten Brummelaar |first9=Theo |last10=Franz |first10=Otto G. |year=1999 |doi=10.1086/300823 |doi-access=free }}