2MASS J12195156+3128497
Template:Short description Template:Sky Template:Starbox begin Template:Starbox image Template:Starbox observe Template:Starbox character Template:Starbox astrometry Template:Starbox detail Template:Starbox catalog Template:Starbox reference Template:Starbox end
2MASS J12195156+3128497 (abbreviated to 2MASS J1219+3128) is a rapidly-rotating brown dwarf of spectral class L8, located in the constellation Coma Berenices about 66 light-years from Earth. With a photometrically measured rotation period of 1.14 hours, it is one of the fastest-rotating known brown dwarfs announced by a team of astronomers led by Megan E. Tannock in March 2021. With a rotational velocity of about Template:Cvt, it is approaching the predicted rotational speed limit beyond which it would break apart due to centripetal forces. As a consequence of its rapid rotation, the brown dwarf is slightly flattened at its poles to a similar degree as Saturn, the most oblate planet in the Solar System.[1] Its rapid rotation may enable strong auroral radio emissions via particle interactions in its magnetic field, as observed in other known rapidly-rotating brown dwarfs.[2]
Discovery
2MASS J1219+3128 was first catalogued as a point source in June 2003 by the Two Micron All-Sky Survey (2MASS) organized by the University of Massachusetts Amherst and the Infrared Processing and Analysis Center under the California Institute of Technology.[3] It was discovered to be a brown dwarf of the spectral class L8 by K. Chiu and collaborators, based on near-infrared observations obtained from the Sloan Digital Sky Survey (SDSS) at Apache Point Observatory in New Mexico, United States. Their discovery and classification of 71 L and T dwarfs including 2MASS J1219+3128 (designated alternatively as SDSS J121951.45+312849.4) was published in The Astronomical Journal in June 2006.[4]
Distance
The distance of 2MASS J1219+3128 from Earth has not yet been measured with trigonometric parallax, so instead it is calculated from the spectrophotometric relation of spectral type and near-infrared absolute magnitude.[5] Schmidt et al. (2010) estimate a spectrophotometric distance of Template:Convert from combined SDSS iz-band and 2MASS JHK-band photometry[6] whereas Buenzli et al. (2014) estimate a spectrophotometric distance of Template:Convert from 2MASS H-band photometry.[5]
Proper motion
2MASS J1219+3128 has a net proper motion of 238.2 mas/yr with position angle 257.98 degrees,Template:EfnTemplate:Efn indicating motion in south-west direction on the sky.[6]
See also
The other two discoveries of rapidly-rotating brown dwarfs, presented in Tannock et al. (2021):[2]
- 2MASS J04070752+1546457 – L3.5 spectral class brown dwarf with a period of Template:Val
- 2MASS J03480772−6022270 – T7 spectral class brown dwarf with a period of Template:Val
Notes
References
External links
- Trio of Fast-Spinning Brown Dwarfs May Reveal a Rotational Speed Limit, Calla Cofield, Jet Propulsion Laboratory, 7 April 2021
- Western space scientists identify fastest-spinning "failed stars" ever found, Jeff Renaud, University of Western Ontario, 7 April 2021
- Caught Speeding: Clocking the Fastest-Spinning Brown Dwarfs, NOIRLab, 7 April 2021
Template:Stars of Coma Berenices Template:2021 in space
- ↑ Cite error: Invalid
<ref>tag; no text was provided for refs namedJPL-20210407 - ↑ 2.0 2.1 Cite error: Invalid
<ref>tag; no text was provided for refs namedTannock2021 - ↑ Cite error: Invalid
<ref>tag; no text was provided for refs namedCutri2003 - ↑ Cite error: Invalid
<ref>tag; no text was provided for refs namedChiu2006 - ↑ 5.0 5.1 Cite error: Invalid
<ref>tag; no text was provided for refs namedBuenzli2014 - ↑ 6.0 6.1 Cite error: Invalid
<ref>tag; no text was provided for refs namedSchmidt2010