72 Leonis

{{Short description|Single, variable M-type giant star in the constellation Leo}}

{{Starbox image

| image=

{{Location mark

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

|label=|position=right

|mark=Red circle.svg|mark_width=10|mark_link=72 Leonis

|x=324|y=300

}}

|caption=Location of 72 Leonis (circled)

}}

{{Starbox observe

| epoch =J2000

| constell = Leo

| ra = {{RA|11|15|12.22709}}

| dec = {{DEC|+23|05|43.8373}}

| appmag_v = 4.63

}}

{{Starbox character

| type =

| class = M3 IIb

| b-v = {{Val|1.657|0.003}}

| u-b =

| variable = LC

}}

{{Starbox astrometry

| radial_v = {{Val|14.76|0.21}}

| prop_mo_ra = −25.56

| prop_mo_dec = −6.00

| parallax = 3.40

| p_error = 0.65

| parallax_footnote =

| absmag_v = −2.69

}}

{{Starbox detail

| source =

| mass = 3.11

| radius = 195

| luminosity = 5,770

| temperature = {{Val|3613|48|fmt=commas}}

| metal_fe = {{val|-0.03}}

| gravity = 1.16

| rotational_velocity =

| age_myr = 400

}}

{{Starbox catalog

| names={{odlist | V=FN Leo | F=72 Leo | BD=+23°2322 | FK5=2897 | HD=97778 | HIP=54951 | HR=4362 | SAO=81736 | AAVSO=1109+23 }}

}}

{{Starbox reference

| Simbad=72+Leo

}}

File:Leonis72.png star 72 Leonis]]

72 Leonis is a single variable star in the zodiac constellation of Leo, located roughly 1,000 light years away from the Sun. It has the variable star designation FN Leonis; 72 Leonis is the Flamsteed designation. In Chinese astronomy, 72 Leonis is called 虎賁, Pinyin: Hǔbēn, meaning Emperor’s Bodyguard, because this star is marking itself and stands alone in the Emperor’s Bodyguard asterism, Supreme Palace enclosure mansion (see : Chinese constellation).

This object is visible to the naked eye as a red-hued star with an apparent visual magnitude of 4.56. It is an evolved bright giant with a stellar classification of M3 IIb and was listed as a spectral standard star for that class. The star is classified as an irregular variable of type LC, ranging from Hipparcos magnitude 4.56 down to 4.64. It has a radius 162 to 179 times that of the Sun and radiates 5,407 times the Sun's luminosity at an effective temperature of around 3,734 K. The star is moving away from the Earth with a heliocentric radial velocity of 15 km/s.

File:FNLeoLightCurve.png for FN Leonis, plotted from Hipparcos data ]]

References

{{reflist|refs=

{{citation |bibcode=2018AJ....155...30B |title=Fundamental Parameters of 87 Stars from the Navy Precision Optical Interferometer |last1=Baines |first1=Ellyn K. |last2=Armstrong |first2=J. Thomas |last3=Schmitt |first3=Henrique R. |last4=Zavala |first4=R. T. |last5=Benson |first5=James A. |last6=Hutter |first6=Donald J. |last7=Tycner |first7=Christopher |last8=Van Belle |first8=Gerard T. |journal=The Astronomical Journal |year=2018 |volume=155 |issue=1 |pages=30 |doi=10.3847/1538-3881/aa9d8b |arxiv=1712.08109 |s2cid=119427037 |postscript=. |doi-access=free }}

{{citation |bibcode=2017MNRAS.471..770M |title=Fundamental parameters and infrared excesses of Tycho-Gaia stars |last1=McDonald |first1=I. |last2=Zijlstra |first2=A. A. |last3=Watson |first3=R. A. |journal=Monthly Notices of the Royal Astronomical Society |year=2017 |volume=471 |issue=1 |pages=770 |doi=10.1093/mnras/stx1433 |doi-access=free |arxiv=1706.02208 |s2cid=73594365 |postscript=. }}

{{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=Validation of the new Hipparcos reduction | last1=van Leeuwen | first1=F. | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | date=2007 | arxiv=0708.1752 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 | s2cid=18759600 | postscript=. }}

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

{{cite web |title=Hipparcos Tools Interactive Data Access |url=https://www.cosmos.esa.int/web/hipparcos/interactive-data-access |website=Hipparcos |publisher=ESA |access-date=8 December 2021}}

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

{{citation

| display-authors=1 | last1=Dyck | first1=H. M. | last2=Van Belle | first2=G. T. | last3=Thompson | first3=R. R. | title=Radii and Effective Temperatures for K and M Giants and Supergiants. II | journal=The Astronomical Journal | volume=116 | issue=2 | pages=981 | year=1998 | doi=10.1086/300453 | bibcode=1998AJ....116..981D | citeseerx=10.1.1.24.1889 | s2cid=16674990 | postscript=. }}

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

{{citation | title=XHIP: An extended hipparcos compilation | last1=Anderson | first1=E. | last2=Francis | first2=Ch. | journal=Astronomy Letters | volume=38 | issue=5 | pages=331 | year=2012 | bibcode=2012AstL...38..331A | arxiv=1108.4971 | doi=10.1134/S1063773712050015 | s2cid=119257644 | postscript=. }}

{{Citation | last1=Kaler | first1=James B. | title=72 Leonis | date=May 11, 2012 | website=stars.astro.illinois.edu | url=http://stars.astro.illinois.edu/sow/72leo.html | access-date=2017-10-09 | postscript=. }}

{{citation|url=http://www.ianridpath.com/startales/leo.htm |publisher=Ian Ridpath's Startales |title=Leo the Lion |access-date=2019-02-10 | postscript=. }}

{{citation|bibcode=2002yCat.2237....0D|title=VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system|journal=CDS/ADC Collection of Electronic Catalogues|volume=2237|last1=Ducati|first1=J. R.|year=2002 | postscript=. }}

}}

Category:M-type bright giants

Category:Slow irregular variables

Category:Leo (constellation)

Category:Durchmusterung objects