kappa2 Coronae Australis

{{hatnote|For other star systems with this Bayer designation see κ Coronae Australis}}

{{Starbox begin

| name = κ² Coronae Australis

}}

{{Starbox image

| image = {{Location mark

| width = 280

| image = Corona Australis constellation map.svg

| float = center |position = right

| mark = Red circle.svg | mark_width = 6 | mark_link = Kappa2 Coronae Australis

| x = 574 | y = 277

}}

| caption = Location of Kappa² CrA (circled)

}}

{{Starbox observe

| constell = Corona Australis

| epoch = J2000.0 (ICRS)

| ra = {{RA|18|33|23.13130}}

| dec = {{DEC|-38|43|33.5392}}

| appmag_v = 5.59{{±|0.01}}

}}

{{Starbox character

| type =

| class = B9 Vnn

| b-v = −0.06

| variable =

}}

{{Starbox astrometry

| radial_v = −15.0{{±|7.4}}

| prop_mo_ra = −2.911

| prop_mo_dec = −20.468

| pm_footnote =

| parallax = 4.6115

| p_error = 0.0747

| parallax_footnote =

| absmag_v =

}}

{{Starbox detail

| mass = 3.12{{±|0.41|0.37}}

| radius = 5.28{{±|0.28}}

| luminosity = 460

| temperature = 12,600

| metal_fe = −0.10

| gravity = 3.58{{±|0.07}}

| rotational_velocity =

| age_gyr =

}}

{{Starbox catalog

| names = {{odlist | B=κ² CrA | CD=−38°12895 | HD=170868 | HIP=90968 | HR=6953 | SAO=210294, 210295 | GC=25314 | CCDM=J18334-3843A | WDS=J18334-3844A | Gould=17 G. Coronae Australis }}

}}

{{Starbox reference

| Simbad = HD+170868

}}

Kappa² Coronae Australis (Kappa² CrA), Latinized from κ² Coronae Australis, is the primary of a probable binary system located in the southern constellation Corona Australis. It is visible to the naked eye as a bluish-white hued star with an apparent visual magnitude of 5.59. The distance to this star is roughly 710 light years based on Gaia DR3 parallax measurements. The radial velocity is poorly constrained, but the star appears to be moving closer with a radial velocity of around {{val|-15|ul=km/s}}. At its current distance, Kappa² CrA's brightness is diminished by 0.45 magnitudes due to interstellar dust.

This is an ordinary B-type main-sequence star with a stellar classification of B9Vnn, with the nn meaning extremely nebulous absorption lines, usually due to rapid rotation. It has 3.12 times the mass of the Sun and a radius 5.28 times larger than the Sun, which is large for stars of this type. It radiates 460 times the luminosity of the Sun from its photosphere at an effective temperature of {{val|12600|ul=K|fmt=commas}}. The large radius combined with the high luminosity of the star may indicate that Kappa² CrA is highly evolved.{{citation needed|date=March 2023}}

Kappa² CrA forms a binary star with Kappa¹ Coronae Australis, also known as HR 6952. Kappa¹ is located 20.5" away along a position angle of 359°. The two were once thought to be an optical pair due to the large difference in their parallaxes but are now considered to be physical based on Gaia measurements. The satellite places Kappa¹ and Kappa² around 700 light years away.

References

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}}

External links

[http://www.alcyone.de/cgi-bin/search.pl?object=HR6952 Alcyone.de] {{Webarchive|url=https://web.archive.org/web/20150123064456/http://www.alcyone.de/cgi-bin/search.pl?object=HR6952 |date=2015-01-23 }}
[http://www.alcyone.de/cgi-bin/search.pl?object=HR6953 Alcyone.de] {{Webarchive|url=https://web.archive.org/web/20150123064612/http://www.alcyone.de/cgi-bin/search.pl?object=HR6953 |date=2015-01-23 }}
[http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%402351885&Name=HR%20%206952&submit=submit Simbad.u-strasbg.fr]
[http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%402351842&Name=HR%20%206953&submit=submit Simbad.u-strasbg.fr]
[http://server7.wikisky.org/starview?object_type=1&object_id=3617 Server7.wikisky.org]
[http://server7.wikisky.org/starview?object_type=1&object_id=7355 Server7.wikisky.org]

Corona Australis, Kappa2

Category:Corona Australis

Corona Australis, Kappa2

Coronae Australis, 17