30 Arietis#30 Arietis Bb
{{Short description|Multiple star system in the constellation Aries}}
{{Starbox begin
| name = 30 Arietis
}}
{{Starbox image
| image = 280px
| caption = 30 Arietis star system hierarchy
| credit =
}}
{{Starbox observe 2s
| epoch = J2000
| constell = Aries
| component1 = 30 Arietis A
| dec1 = {{DEC|+24|38|49.9880}}
| appmag_v1 =
| component2 = 30 Arietis B
| dec2 = {{DEC|+24|38|53.0026}}
| appmag_v2 =
| component3 = 30 Arietis C
| ra3 =
| dec3 =
| appmag_v3 =
| component4 = 30 Arietis D
| ra4 =
| dec4 =
| appmag_v4 =
}}
{{Starbox character
| r-i =
| v-r =
| u-b =
| variable =
}}
{{Starbox astrometry
| component1 = 30 Arietis A
| radial_v =
| prop_mo_ra = {{val|136.862|0.137}}
| prop_mo_dec = {{val|−15.188|0.141}}
| parallax = 22.1261
| p_error = 0.0726
| absmag_v =
| component2 = 30 Arietis B
| radial_v2 =
| prop_mo_ra2 = {{val|141.411|0.083}}
| prop_mo_dec2 = {{val|−10.677|0.086}}
| parallax2 = 22.3641
| p_error2 = 0.0516
| absmag_v2 =
}}
{{Starbox orbit
| primary = 30 Arietis A
| name = 30 Arietis BC
| period = 34000
| period_unitless =
| axis = 40
| axis_unitless = 1670 AU
| eccentricity =
| inclination =
| node =
| periastron =
| periarg =
| periarg_primary =
| k1 =
| k2 =
}}
{{Starbox orbit
| primary = 30 Arietis B
| name = 30 Arietis C
| period = 80
| period_unitless =
| axis =
| axis_unitless = 22.3 AU
| eccentricity =
| inclination =
| node =
| periastron =
| periarg =
| periarg_primary =
| k1 =
| k2 =
}}
{{Starbox orbit
| primary = 30 Arietis B
| name = 30 Arietis Bb
| period = 0.917 ± 0.007
| period_unitless = 335.1 ± 2.5 d
| axis =
| axis_unitless = 0.995 ± 0.012 AU
| eccentricity = 0.289 ± 0.092
| inclination = {{val|4.14|0.96|0.90}}°
| node =
| periastron =
| periarg =
| periarg_primary =
| k1 =
| k2 =
}}
{{Starbox detail
| component1 = 30 Arietis A
| luminosity =
| temperature =
| metal =
| rotation =
| component2 = 30 Arietis Ba
| luminosity2 =
| temperature2 =
| metal2 =
| rotation2 =
}}
{{Starbox detail
| component1 = 30 Arietis Bb
}}
{{Starbox catalog
| names = CCDM 02370+2439, WDS 02370+2439
30 Arietis A
BD+24°376, HD 16246, HIP 12189, HR 765, SAO 75471
30 Arietis B
BD+24°375, HD 16232, HIP 12184, HR 764, SAO 75470
}}
{{Starbox reference
| Simbad = 30+Ari+A|sn=A
| Simbad3 = 30+Ari+B|sn3=B
| NSTED = 30+Ari+B
| EPE = 30+Ari+B
}}{{starbox sources|HIP|CCDM|HR}}
{{Starbox end}}
30 Arietis (abbreviated 30 Ari) is a 6th-apparent-magnitude multiple star system in the constellation of Aries. 30 Arietis is the Flamsteed designation. 30 Arietis A and B are separated by {{val|38.1|ul="}} or about {{val|1500|ul=AU|fmt=commas}} at a distance of 130 light years away. The main components of both systems are both binaries with a composite spectra belonging to F-type main-sequence stars, meaning they are fusing hydrogen in their cores. The 30 Arietis system is 910 million years old, one fifth the age of the Sun.
Star system
30 Arietis A and B are separated by 38.1", corresponding to 1,500 AU at a distance of 130 light years. The pair are at almost the same distance, have very similar proper motions, and are considered almost certain to be gravitationally bound with a likely period around 34,000 years. The main components of both systems are both binaries with a composite spectra belonging to F-type main-sequence stars, meaning they are fusing hydrogen in their cores.
30 Arietis A is a spectroscopic binary with an orbital period of 1.1 days. The primary Aa is an F-type main sequence star about 31% more massive than the Sun, while the companion Ab is a faint red dwarf only about 15% the mass of the Sun.
30 Arietis B has been reported to have a red dwarf companion at a distance of {{val|22|u=AU}} and another red dwarf Bb at about {{val|1|ul=AU}}. In 2020, after the inclination of the planetary orbit was measured, the "planet" was found to fall in the mass range of a brown or red dwarf. The more distant companion was referred to as C to distinguish it from Bb, and at about 0.5" it has been imaged using adaptive optics.
30 Arietis Bb
30 Arietis Bb (sometimes abbreviated 30 Ari Bb) is a red dwarf which orbits the F-type main sequence star 30 Arietis Ba, located in a quintuple star system approximately 146 light years away in the constellation Aries. The red dwarf, initially believed to be a massive planet or brown dwarf, was announced in a paper published online on September 24, 2009. It was discovered by using precision radial velocity measurements from the echelle spectrograph installed on the Alfred-Jensch telescope in Karl Schwarzschild Observatory. The star had a minimum mass of nearly 10 times that of Jupiter.{{cite encyclopedia |url=https://exoplanet.eu/catalog/30_ari_b_b--618/ |title=Notes for Planet 30 Ari B b |author=Jean Schneider |year=2011 |encyclopedia=Extrasolar Planets Encyclopaedia |access-date=3 October 2011}} In 2020, after the inclination of the planetary orbit was measured to be just 4.14{{±|0.96|0.90}}°, the "planet" was found to fall in the mass range of red dwarf stars.
See also
References
{{Reflist|refs=
{{cite Gaia DR2|102082409030066560}}
{{cite Gaia DR2|102082477749475200}}
{{cite web |url=http://www.nasa.gov/jpl/planet-reared-by-four-parent-stars/index.html |title=Planet 'Reared' by Four Parent Stars |author=Whitney Clavin |date=2015 |publisher=NASA |access-date=4 March 2015 |archive-date=4 March 2016 |archive-url=https://web.archive.org/web/20160304225833/http://www.nasa.gov/jpl/planet-reared-by-four-parent-stars/index.html |url-status=dead }}
}}
External links
- [https://web.archive.org/web/20071010212147/http://www.nckas.org/images/objects/sao75471.jpg Image 30 Arietis]
- [https://web.archive.org/web/20080615144206/http://www.nckas.org/doublestars/ Double stars]
- [http://www.nasa.gov/jpl/18927/ NASA diagram of the 30 Ari System] {{Webarchive|url=https://web.archive.org/web/20160220074405/http://www.nasa.gov/jpl/18927/ |date=2016-02-20 }}
{{Stars of Aries}}
{{Sky|02|36|00.5237|+|24|38|50.000|128.6}}
Category:Aries (constellation)