HD 96919

{{Short description|Variable star in the constellation Carina}}

{{about|z² Carinae|other stars with the same Bayer designation or for Z Carinae|Z Carinae}}

{{starbox begin

| name=V371 Carinae

}}

{{Starbox image

| image=

{{Location mark

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

|label=|position=right

|mark=Red circle.svg|mark_width=8|mark_link=V371 Car

|x=110|y=468

}}

|caption=Location of V371 Carinae (circled)

}}

{{starbox observe

| epoch=J2000

| constell=Carina

| ra={{RA|11|08|33.99848}}{{cite journal|bibcode=2007A&A...474..653V|title=Validation of the new Hipparcos reduction|journal=Astronomy and Astrophysics|volume=474|issue=2|pages=653–664|last1=Van Leeuwen|first1=F.|year=2007|doi=10.1051/0004-6361:20078357|arxiv = 0708.1752 |s2cid=18759600}}

| dec={{DEC|−61|56|49.8316}}

| appmag_v=5.19{{cite journal|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|pages=0|last1=Ducati|first1=J. R.|year=2002}} {{nowrap|(5.12 - 5.19{{cite journal|bibcode=2009yCat....102025S|title=VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)|journal=VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S|volume=1|display-authors=etal|last1=Samus|first1=N. N.|last2=Durlevich|first2=O. V.|year=2009}})}}

}}

{{starbox character

| class=B9 Iae

| b-v=+0.23

| u-b=−0.46

| variable=α Cyg

}}

{{starbox astrometry

| radial_v=−22.4 ± 2{{cite journal|bibcode=1953GCRV..C......0W|title=General catalogue of stellar radial velocities|journal=Washington|last1=Wilson|first1=Ralph Elmer|year=1953}}

| prop_mo_ra=−5.78

| prop_mo_dec=1.74

| parallax=0.23

| p_error=0.25

| parallax_footnote=

| dist_pc=1,920

| absmag_v=−7.0{{cite journal|bibcode=2010A&A...514A..59K|title=The Carina spiral feature: Strömgren-β photometry approach. II. Distances and space distribution of the O and B stars|journal=Astronomy and Astrophysics|volume=514|pages=A59|last1=Kaltcheva|first1=N.|last2=Scorcio|first2=M.|year=2010|doi=10.1051/0004-6361/200913399|doi-access=free}}

}}

{{Starbox detail

| mass=23{{cite journal|bibcode=1996A&A...305..887K|title=Long-term spectroscopic monitoring of BA-type supergiants. I. Halpha_ line-profile variability|journal=Astronomy and Astrophysics|volume=305|pages=887|last1=Kaufer|first1=A.|last2=Stahl|first2=O.|last3=Wolf|first3=B.|last4=Gaeng|first4=T.|last5=Gummersbach|first5=C. A.|last6=Kovacs|first6=J.|last7=Mandel|first7=H.|last8=Szeifert|first8=T.|year=1996}}

| temperature=12,500{{cite journal|bibcode=2013MNRAS.433.1246S|title=Evolution of blue supergiants and α Cygni variables: Puzzling CNO surface abundances|journal=Monthly Notices of the Royal Astronomical Society|volume=433|issue=2|pages=1246|last1=Saio|first1=Hideyuki|last2=Georgy|first2=Cyril|last3=Meynet|first3=Georges|year=2013|doi=10.1093/mnras/stt796|doi-access=free |arxiv = 1305.2474 |s2cid=119295289}}

| radius=141

| luminosity=105,000

| gravity=1.50

| rotational_velocity=60

}}

{{starbox catalog

| names=z² Carinae, V371 Carinae, 261 G. Carinae,{{cite journal|bibcode=1879RNAO....1....1G|title=Brightness and position of every star, down to the seventh magnitude, within one hundred degrees of the South Pole|journal=Resultados del Observatorio Nacional Argentino|volume=1|last1=Gould|first1=Benjamin Apthorp|year=1879|pages=I}} CD−61°2941, CPD−61°2075, CPC 20.1 3080, FK5 2891, GC 15331, GCRV 6856, GSC 08962-02640, HD 96919, HIC 54461, HIP 54461, HR 4338, PPM 358516, SAO 251286

}}

{{Starbox reference

|Simbad=V371+Car

}}

{{starbox end}}

HD 96919, also known by its Bayer designation of z² Carinae and the variable star designation of V371 Carinae, is a blue supergiant star in the constellation Carina. It lies near the Carina Nebula and at a comparable distance. A 5th magnitude star, it is visible to the naked eye under good observing conditions.

File:V371CarLightCurve.png for V371 Carinae, plotted from Hipparcos data]]

In 1977, Christiaan Sterken announced his discovery that HD 96919 is a variable star. It was given its variable star designation in 1979. V371 Car is an α Cyg variable, erratically pulsating and changing brightness by a few hundredths of a magnitude. Periods of 10–80 days have been identified. It shows unusual emission lines in its spectrum, and high-velocity absorption (HVA) events, temporary spectral features that are thought to indicate localised regions of enhanced mass loss.{{cite journal|bibcode=1996A&A...314..599K|title=Long-term spectroscopic monitoring of BA-type supergiants. II. High-velocity absorptions in βOri and HD96919|journal=Astronomy and Astrophysics|volume=314|pages=599|last1=Kaufer|first1=A.|last2=Stahl|first2=O.|last3=Wolf|first3=B.|last4=Gaeng|first4=T.|last5=Gummersbach|first5=C. A.|last6=Jankovics|first6=I.|last7=Kovacs|first7=J.|last8=Mandel|first8=H.|last9=Peitz|first9=J.|last10=Rivinius|first10=T.|last11=Szeifert|first11=T.|year=1996}}

HD 96919 is a B9 supergiant, possibly located 6,000 light-years from Earth. It is considered to be a post-red supergiant star, either evolving towards a Wolf–Rayet star or on a blue loop before returning to a cooler temperature.