9 Boötis

{{Starbox observe

| epoch = J2000

| constell = Boötes

| ra = {{RA|13|56|34.18103}}

| dec = {{DEC|+27|29|31.4932}}

| appmag_v = 5.02

}}

{{Starbox character

| type = AGB

| class = K3 III

| b-v = {{Val|1.441|0.005}}

| u-b =

| variable = suspected irregular

}}

{{Starbox astrometry

| radial_v = {{Val|−41.07|0.14}}

| prop_mo_ra = +28.154

| prop_mo_dec = −48.279

| parallax = 5.2113

| p_error = 0.1011

| parallax_footnote =

| absmag_v = −1.23

}}

{{Starbox detail

| mass = {{val|3.5|0.5}}

| radius = 44

| luminosity = 857

| temperature = 4,197

| metal_fe = −0.27

| gravity = 1.85

| rotational_velocity = 1.5

| age_myr =

}}

{{Starbox catalog

| names={{odlist | F=9 Boo | BD=+28°2278 | HD=121710 | HIP=68103 | HR=5247 | SAO=83084 | GC=18850 | NSV=6502 }}

}}

{{Starbox reference

| Simbad=9+Boo

}}

9 Boötis is a single, variable star in the northern constellation of Boötes, located around 630 light years away from the Sun. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.0. This object is moving closer to the Earth with a heliocentric radial velocity of −41 km/s.

This is an aging giant star with a stellar classification of K3 III, which indicates it has exhausted the hydrogen at its core and evolved of the main sequence. As a consequence, its outer atmosphere has swollen to 44 times the radius of the Sun. It is a suspected irregular variable that ranges in photographic magnitude from 6.1 down to 6.6. 9 Boötis is considered mildly lithium-rich with a moderate level of chromospheric activity. It is radiating 857 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,197 K.

References

{{reflist|refs=

{{cite journal |bibcode=2000A&A...359..563C |title=The Nature of the lithium rich giants. Mixing episodes on the RGB and early-AGB |last1=Charbonnel |first1=C. |last2=Balachandran |first2=S. C. |journal=Astronomy and Astrophysics |date=2000 |volume=359 |page=563 |arxiv=astro-ph/0005280 }}

{{citation

| title=On Infrared Excesses Associated with Li-rich K Giants

| display-authors=1 | last1=Rebull | first1=Luisa M.

| last2=Carlberg | first2=Joleen K. | last3=Gibbs | first3=John C.

| last4=Deeb | first4=J. Elin | last5=Larsen | first5=Estefania

| last6=Black | first6=David V. | last7=Altepeter | first7=Shailyn

| last8=Bucksbee | first8=Ethan | last9=Cashen | first9=Sarah

| last10=Clarke | first10=Matthew | last11=Datta | first11=Ashwin

| last12=Hodgson | first12=Emily | last13=Lince | first13=Megan

| journal=The Astronomical Journal | postscript=.

| doi=10.1088/0004-6256/150/4/123 | bibcode=2015AJ....150..123R | arxiv=1507.00708 | s2cid=46595131 }}

{{citation | postscript=.

| title= The Perkins catalog of revised MK types for the cooler stars

| journal= Astrophysical Journal Supplement Series

| last1=Keenan |first1=Philip C. |last2=McNeil |first2=Raymond C.

| issn=0067-0049 | volume=71 | pages=245 | year=1989

| bibcode= 1989ApJS...71..245K | doi= 10.1086/191373 }}

{{citation

| 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

| doi=10.1111/j.1365-2966.2008.13596.x | doi-access=free | postscript=.

| bibcode=2008MNRAS.389..869E | arxiv=0806.2878 | s2cid=14878976 }}

{{citation | postscript=.

| last=McWilliam | first=Andrew

| title=High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances

| journal=Astrophysical Journal Supplement Series

| volume=74 | pages=1075–1128 | date=December 1990

| doi=10.1086/191527 | bibcode=1990ApJS...74.1075M | doi-access=free}}

{{citation

| title=Lithium and rapid rotation in chromospherically active single giants

| last1=Fekel | first1=Francis C. | last2=Balachandran | first2=Suchitra

| journal=Astrophysical Journal, Part 1 | postscript=.

| volume=403 | issue=2 | pages=708–721 | date=February 1993

| doi=10.1086/172242 | bibcode=1993ApJ...403..708F }}

{{citation

| display-authors=1 | last1=Samus | first1=N. N.

| last2=Kazarovets | first2=E. V. | last3=Durlevich | first3=O. V.

| last4=Kireeva | first4=N. N. | last5=Pastukhova | first5=E. N.

| title=General Catalogue of Variable Stars

| version=5.1 | journal=Astronomy Reports

| year=2017 | volume=61 | issue=1 | pages=80–88

| doi=10.1134/S1063772917010085 | bibcode=2017ARep...61...80S | s2cid=125853869 | postscript=. }}

{{citation

| title=NSV 6502 | publisher=American Association of Variable Star Observers

| work=The International Variable Star Index

| url=https://www.aavso.org/vsx/index.php?view=detail.top&oid=45126

| access-date=2019-04-26 | postscript=. }}

{{citation

| title=XHIP: An extended hipparcos compilation

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

| journal=Astronomy Letters | postscript=.

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

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

| doi=10.1134/S1063773712050015 | s2cid=119257644 }}

}}

Category:K-type giants

Category:Suspected variables

Category:Irregular variables

Category:Boötes

Category:Durchmusterung objects

Category:Asymptotic-giant-branch stars