Epoch 2012.855 Equinox J2000
|Right ascension||20h 30m 42.897s|
|Declination||07° 49′ 34.44″|
|Apparent magnitude (i (SDSS))||21.810 ± 0.140|
|Apparent magnitude (z (SDSS))||17.195 ± 0.014|
|Apparent magnitude (J (2MASS))||14.227 ± 0.029|
|Apparent magnitude (H (2MASS))||13.435 ± 0.033|
|Apparent magnitude (Ks (2MASS))||13.319 ± 0.039|
|Apparent magnitude (w1 (WISE))||12.956 ± 0.025|
|Apparent magnitude (w2 (WISE))||12.122 ± 0.025|
|Apparent magnitude (w3 (WISE))||10.964 ± 0.110|
|Proper motion (μ)||RA: 653 ± 6 mas/yr
Dec.: -138 ± 16 mas/yr
|Distance||34.2 ± 8.5 ly
(10.5 ± 2.6 pc)
History of observations
Mace et al. selected T-type brown dwarf candidates from WISE All-Sky source catalogue and carried out follow up observations using a variety of telescopes. September 11, 2011 WISE J2030+0749 was observed using SpeX at Infrared Telescope Facility (IRTF). The discovery paper was submitted to The Astrophysical Journal Supplement, accepted for publication on 2013 January 15 and published in March, 2013. The total number of announced in Mace et al. (2013) brown dwarfs is 87, all are of T-type.
Bihain et al. selected sources with colours typical for T dwarfs from WISE All-Sky source catalogue and checked them for high proper motion using older surveys: 2MASS, DENIS, SDSS, SSS, DSS and UKIDSS. Three objects among about ten candidates, including WISE J2030+0749, were selected for spectroscopic follow up with Large Binocular Telescope (LBT). November 8, 2012 Bihain et al. carried out follow up observations of WISE J2030+0749 with near-Infrared spectrograph LUCI 1 on LBT. June 25, 2013 Astronomy & Astrophysics received the discovery paper, which was accepted for publication 10 July 2013.
Distance of WISE J2030+0749 was estimated by Bihain et al. using mean absolute magnitudes of single T1/T2 dwarfs, derived by Dupuy & Liu (2012) from trigonometric parallaxes: 10.5 ± 2.6 pc (34.2 ± 8.5 ly).
WISE J2030+0749 distance estimates
|Source||Parallax, mas||Distance, pc||Distance, ly||Ref.|
|Bihain et al. (2013)||10.5 ± 2.6||34.2 ± 8.5|||
Non-trigonometric estimates are marked in italic. The best estimate is marked in bold.
Two other T dwarfs, announced in Bihain et al (2013):
- Bihain, Gabriel; Ralf-Dieter Scholz, Jesper Storm, Olivier Schnurr (2013). "An overlooked brown dwarf neighbour (T7.5 at d~5pc) of the Sun and two additional T dwarfs at about 10pc". arXiv:1307.2722. Bibcode 2013arXiv1307.2722B.
- Mace, Gregory N.; Kirkpatrick, J. Davy; Cushing, Michael C.; Gelino, Christopher R.; Griffith, Roger L.; Skrutskie, Michael F.; Marsh, Kenneth A.; Wright, Edward L.; Eisenhardt, Peter R.; McLean, Ian S.; Thompson, Maggie A.; Mix, Katholeen; Bailey, Vanessa; Beichman, Charles A.; Bloom, Joshua S.; Burgasser, Adam J.; Fortney, Jonathan J.; Hinz, Philip M.; Knox, Russell P.; Lowrance, Patrick J.; Marley, Mark S.; Morley, Caroline V.; Rodigas, Timothy J.; Saumon, Didier; Sheppard, Scott S.; Stock, Nathan D. (2013). "A Study of the Diverse T Dwarf Population Revealed by WISE". The Astrophysical Journal Supplement 205 (1): 6. arXiv:1301.3913. Bibcode:2013ApJS..205....6M. doi:10.1088/0067-0049/205/1/6.
- Dupuy, Trent J.; Liu, Michael C. (2012). "The Hawaii Infrared Parallax Program. I. Ultracool Binaries and the L/T Transition". The Astrophysical Journal Supplement 201 (2): 19. arXiv:1201.2465. Bibcode:2012ApJS..201...19D. doi:10.1088/0067-0049/201/2/19.