2MASS J09373487+2931409

2MASS 0937+2931 was discovered in 2002 by Adam J. Burgasser et al. from Two Micron All-Sky Survey (2MASS), conducted from 1997 to 2001. Follow-up observations were made in 1998–2001 using the Near-Infrared Camera, mounted on the Palomar 60 inch (1.5 m) Telescope; CTIO Infrared Imager (CIRIM) and Ohio State Infrared Imager/Spectrometer (OSIRIS), mounted on the Cerro Tololo Inter-American Observatory (CTIO) 1.5 m Telescope; and some additional observations were made using the Near Infrared Camera (NIRC), mounted on the Keck I 10 m telescope, and nearinfrared camera D78, mounted on the Palomar 5 m Hale Telescope. In 2002 Burgasser et al. published a paper, where they defined new spectral subtypes T1—T8, and presented discovery of 11 new T-type brown dwarfs, among which also was 2MASS 0937+2931. This 11 objects were among the earliest T-type brown dwarfs ever discovered: before this, the total number of known T-type objects was 13, and this discoveries increased it up to 24 (apart from additional T-type dwarfs, identified by Geballe et al. 2001 in SDSS data).{{r|Burgasser2002}}

Currently the most precise distance estimate of 2MASS 0937+2931 is trigonometric parallax, published in 2009 by Schilbach et al.: 163.39 ± 1.76 mas, corresponding to a distance 6.12 ± 0.07 pc, or 19.96 ± 0.22 ly.{{r|Schilbach2009}} A less precise parallax of this object, measured under U.S. Naval Observatory Infrared Astrometry Program, was published in 2004 by Vrba et al.{{r|Vrba2004}}

2MASS 0937+2931 has an unusual spectrum, indicating a metal-poor atmosphere and/or a high surface gravity (high pressure at the surface).{{r|Burgasser2002}} Its effective temperature is estimated at 800 Kelvin. The Research Consortium On Nearby Stars (RECONS) estimates the brown dwarf to be 0.03 solar masses.{{r|RECONS}} No optical variability was detected as in 2014.{{citation|arxiv=1412.6733|year=2014|title=Weather on Other Worlds. III. A Survey for T Dwarfs with High-Amplitude Optical Variability|doi=10.1088/0004-637X/801/2/104 |last1=Heinze |first1=Aren N. |last2=Metchev |first2=Stanimir |last3=Kellogg |first3=Kendra |journal=The Astrophysical Journal |volume=801 |issue=2 |page=104 |s2cid=119217978 }}

The other 10 brown dwarfs, presented in Burgasser et al. (2002):

• 2MASS 0243-2453 (T6)
• 2MASS 0415-0935 (T8)
• 2MASS 0727+1710 (T7)
• List of stars in Leo

{{reflist|colwidth=30em|refs =

{{cite web

| url=http://simbad.u-strasbg.fr/simbad/sim-id?Ident=2MASS+J09373487%2B2931409

| title=2MASS J09373487+2931409 -- Brown Dwarf (M<0.08solMass)

| work=SIMBAD

| publisher=Centre de Données astronomiques de Strasbourg

| access-date=2012-11-26}}

{{cite web |website=Research Consortium on Nearby Stars |publisher=Georgia State University |date = January 1, 2012 |title=The 100 nearest star systems |url=http://www.astro.gsu.edu/RECONS/TOP100.posted.htm |access-date = 2012-06-11}}

{{cite journal |last1=Burgasser |first1=Adam J. |last2=Kirkpatrick |first2=J. Davy |author-link2=J. Davy Kirkpatrick |last3=Brown |first3=Michael E. |author-link3=Michael E. Brown |last4=Reid |first4=I. Neill |last5=Burrows |first5=Adam |last6=Liebert |first6=James |last7=Matthews |first7=Keith |last8=Gizis |first8=John E. |last9=Dahn |first9=Conard C. |last10=Monet |first10=David G. |last11=Cutri |first11=Roc M. |last12=Skrutskie |first12=Michael F. |title=The Spectra of T Dwarfs. I. Near-Infrared Data and Spectral Classification |year=2002 |journal=The Astrophysical Journal |volume=564 |issue=1 |pages=421–451 |arxiv=astro-ph/0108452 |doi=10.1086/324033 |bibcode=2002ApJ...564..421B |s2cid=9273465 }}

{{cite journal |last=Vrba |first=F. J. |author2=Henden, A. A. |author3=Luginbuhl, C. B. |author4=Guetter, H. H. |author5=Munn, J. A. |author6=Canzian, B. |author7=Burgasser, Adam J. |author8=Kirkpatrick, J. Davy |author9=Fan, X. |author10=Geballe, T. R. |author11=Golimowski, D. A. |author12=Knapp, G. R. |author13=Leggett, S. K. |author14=Schneider, D. P. |author15=Brinkmann, J. |title=Preliminary Parallaxes of 40 L and T Dwarfs from the US Naval Observatory Infrared Astrometry Program |year=2004 |journal=The Astronomical Journal |volume=127 | issue=5 | pages=2948–2968 |arxiv=astro-ph/0402272 |doi=10.1086/383554 |bibcode=2004AJ....127.2948V|s2cid=16344176 }}

{{cite journal |last=Schilbach |first=E. |author2=Röser, S. |author3=Scholz, R.-D. |title=Trigonometric parallaxes of ten ultracool subdwarfs |year=2009 |journal=Astronomy and Astrophysics |volume=493 | issue=2 | pages=L27–L30 |arxiv=0811.4136 |doi=10.1051/0004-6361:200811281 |bibcode=2009A&A...493L..27S|s2cid=17774863 }}

}}

• Burgasser et al.: [http://cdsads.u-strasbg.fr/abs/2006ApJ...639.1095B A Method for Determining the Physical Properties of the Coldest Known Brown Dwarfs"]; in: The Astrophysical Journal, Vol. 639, Issue 2, S. 1095ff. (2006)
• Cushing et al.: [http://cdsads.u-strasbg.fr/abs/2006ApJ...648..614C A Spitzer Infrared Spectrograph Spectral Sequence of M, L, and T Dwarfs"]; in: The Astrophysical Journal, Vol. 648, Issue 1, S. 614ff. (2006)

{{Nearest systems|4}}

{{Stars of Leo}}

{{DEFAULTSORT:2MASS J09373487+2931409}}

Category:Leo (constellation)

Category:Brown dwarfs

Category:T-type brown dwarfs

J09373487+2931409

Category:Astronomical objects discovered in 2002