18 Aquarii

{{short description|Yellowish star in the constellation Aquarius}}

{{Starbox begin

| name = 18 Aquarii

}}

{{Starbox observe

| epoch = J2000

| ra = {{RA|21|24|11.49206}}

| dec = {{DEC|−12|52|41.1928}}

| appmag_v = 5.49

| constell = Aquarius

}}

{{Starbox character

| class = F0 V

| b-v = +0.29

| u-b =

| variable =

}}

{{Starbox astrometry

| radial_v = {{Val|−3.0|6.9}}

| prop_mo_ra = +89.60

| prop_mo_dec = +8.62

| parallax = 21.23

| p_error = 0.29

| parallax_error =

| absmag_v = 2.12

}}

{{Starbox detail

| mass = 1.54

| radius =

| luminosity = 11.8

| temperature = 7,194

| metal_fe = –0.16

| gravity = 3.98

| rotational_velocity = 138

| age_myr = 480

}}

{{Starbox catalog

| names = {{odlist | F=18 Aqr | BD=−13°5923 | FK5=1562 | HD=203705 | HIP=105668 | HR=8187 | SAO=164364 }}{{cite simbad | title=18 Aqr | access-date=2018-02-02 }}

}}

{{Starbox reference

| Simbad=18+Aqr

}}

18 Aquarii is a single, yellow-white hued star in the equatorial constellation of Aquarius. The designation is from the catalogue of English astronomer John Flamsteed, first published in 1712. The star is faintly visible to the naked eye with an apparent visual magnitude of 5.49 and is located about {{Convert|154|ly|pc|abbr=off|lk=on}} from Earth.

This is an F-type main sequence star with a stellar classification of F0 V. It is an estimated 480 million years old and has a high rate of spin with a projected rotational velocity of 138 km/s. The star has 1.54 times the mass of the Sun and is radiating 11.8 times the Sun's luminosity from its photosphere at an effective temperature of 7,194 K.

References

{{reflist|refs=

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| bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015

| arxiv=1108.4971 | s2cid=119257644 | postscript=. }}

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| bibcode=2015ApJ...804..146D | doi=10.1088/0004-637X/804/2/146

| arxiv=1501.03154 | s2cid=33401607 | postscript=. }}

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{{citation | last1=Royer | first1=F. | last2=Zorec | first2=J. | last3=Gómez | first3=A. E. | title=Rotational velocities of A-type stars. III. Velocity distributions | journal=Astronomy and Astrophysics | volume=463 | issue=2 | pages=671–682 | doi=10.1051/0004-6361:20065224 | bibcode=2007A&A...463..671R | arxiv=astro-ph/0610785 | postscript=. |date=February 2007| s2cid=18475298 }}

{{citation | display-authors=1 | last1=Soubiran | first1=C. | last2=Le Campion | first2=J.-F. | last3=Cayrel de Strobel | first3=G. | last4=Caillo | first4=A. | title=The PASTEL catalogue of stellar parameters | journal=Astronomy and Astrophysics | volume=515 | page=A111 | doi=10.1051/0004-6361/201014247 | bibcode=2010A&A...515A.111S | postscript=. |arxiv = 1004.1069 |date=June 2010| s2cid=118362423 }}

{{citation | title=The VAST Survey - III. The multiplicity of A-type stars within 75 pc | journal=Monthly Notices of the Royal Astronomical Society | last1=De Rosa | first1=R. J. | last2=Patience | first2=J. | last3=Wilson | first3=P. A. | last4=Schneider | first4=A. | last5=Wiktorowicz | first5=S. J. | last6=Vigan | first6=A. | last7=Marois | first7=C. | last8=Song | first8=I. | last9=MacIntosh | first9=B. | last10=Graham | first10=J. R. | last11=Doyon | first11=R. | last12=Bessell | first12=M. S. | last13=Thomas | first13=S. | last14=Lai | first14=O. | volume=437 | issue=2 | pages=1216 | year=2014 | bibcode=2014MNRAS.437.1216D | doi=10.1093/mnras/stt1932 | doi-access=free | arxiv=1311.7141 | postscript=. }}

}}

External links

[http://aladin.u-strasbg.fr/AladinPreview?-c=SV*+ZI++2007&ident=SV*+ZI++2007&submit=Aladin+previewer Image 18 Aquarii]

Category:F-type main-sequence stars

Category:Aquarius (constellation)

Category:Durchmusterung objects