CFBDSIR J145829+101343
CFBDSIR J145829+101343 is a binary system of two brown dwarfs of spectral classes T9 + Y0 orbiting each other, located in constellation Boötes about 104 light-years away from Earth.
The smaller companion, CFBDSIR 1458+10B, has a surface temperature of approx 370 K. It used to be known as the coolest known brown dwarf until the discovery of WISE 1828+2650 in August 2011.
Discovery
CFBDSIR 1458+10 A was discovered in 2010 by Delorme et al. from the Canada-France Brown Dwarf Survey using the facilities MegaCam and mounted on the 3.6 m Canada-France-Hawaii Telescope, located on Mauna Kea Observatory, Hawaii. Image in z` band was taken on 2004 July 15 with MegaCam, and image in J band was taken on 2007 April 1 with WIRCam. In 2009 they made follow-up photometry, using the SOFI near infrared camera at the ESO 3.5 m New Technology Telescope (NTT) at the La Silla Observatory, Chile. In 2010 Delorme et al. published a paper in Astronomy and Astrophysics where they reported the identification of 55 T-dwarfs candidates, six of which were photometrically confirmed as T-dwarfs, including 3 ultracool brown dwarfs, including CFBDSIR 1458+10.Discovery of B
CFBDSIR 1458+10 B was discovered in 2011 by Liu et al. with laser guide star (LGS) adaptive optics (AO) system of the 10 m Keck II Telescope on Mauna Kea, Hawaii, using infra-red camera NIRC2. In 2011 Liu et al. published a paper in The Astrophysical Journal where they presented discovery of CFBDSIR 1458+10 system component B. Also they presented a near-infrared trigonometric parallax of the system, measured using WIRCam on the Canada-France-Hawaii Telescope (CFHT), Mauna Kea, in seven epochs during the 2009–2010; and spectroscopy with the X-Shooter spectrograph at the European Southern Observatory's Very Large Telescope (VLT) Unit Telescope 2 in Chile, that allowed to calculate the temperature of the two brown dwarfs.2012 Keck LGS-AO imaging
In 2012 CFBDSIR 1458+10 system was observed by Liu et al. with laser guide star (LGS) adaptive optics (AO) system of the 10 m Keck II Telescope on Mauna Kea, Hawaii, using infra-red camera NIRC2. In 2012 Liu et al. published a paper in The Astrophysical Journal where they presented results of observations with Keck II LGS-AO of three brown dwarf binary systems, binarity of the two of which was first presented in this paper, and binarity of the other one, CFBDSIR 1458+10, was known before.Distance
Trigonometric parallax of CFBDSIR 1458+10, measured under The Hawaii Infrared Parallax Program by Dupuy & Liu in 2012, is 31.3 ± 2.5 mas, corresponding to a distance 31.9 pc, or 104.2 ly.CFBDSIR 1458+10 distance estimates
| Source | Parallax, mas | Distance, pc | Distance, ly | Ref. |
| Delorme et al. | ~23 | ~75 | ||
| Liu et al. | 43.3 ± 4.5 | 23.1 ± 2.4 | 75.3 ± 7.8 | |
| Dupuy & Liu | 34.0 ± 2.6 | 29.4 | 95.9 | |
| Dupuy & Liu | 31.3 ± 2.5 | 31.9 | 104.2 |
Space motion
CFBDSIR 1458+10 has proper motion of about 420 milliarcseconds per year.CFBDSIR 1458+10 proper motion estimates
| Source | μ, mas/yr | P. A., ° | μRA, mas/yr | μDEC, mas/yr | Ref. |
| Delorme et al. | 444 ± 16 | 157.5 ± 2.1 | 170 ± 16 | −410 ± 16 | |
| Liu et al. | 432 ± 6 | 154.2 ± 0.7 | 188 | −389 | |
| Dupuy & Liu | 418.1 ± 3.2 | 155.4 ± 0.4 | 174.3 ± 3.0 | −380.0 ± 3.2 | |
| Dupuy & Liu | 419.6 ± 2.6 | 155.50 ± 0.28 | 174.0 ± 2.0 | −381.8 ± 2.7 |
Physical properties
Using three models, Liu et al. calculated physical properties of CFBDSIR 1458+10 components.From Lyon/COND models and Lbol:
| Component and assumed age | Mass, MJup | Teff, K | log g, cm/s2 | P, yr |
| A | 12.1 ± 1.9 | 556 ± 48 | 4.45 ± 0.07 | |
| B | 5.8 ± 1.3 | 360 ± 40 | 4.10 ± 0.10 | 35 |
| A | 31 ± 4 | 605 ± 55 | 5.00 ± 0.08 | |
| B | 14 ± 3 | 380 ± 50 | 4.58 ± 0.11 | 22 |
From Burrows et al. :
| Component and assumed age | Mass, MJup | Teff, K | log g, cm/s2 | P, yr |
| A | 13 ± 2 | 550 ± 50 | 4.47 ± 0.07 | |
| B | 6.8 ± 1.5 | 350 ± 40 | 4.14 ± 0.10 | 33 |
| A | 36 ± 4 | 600 ± 60 | 5.06 ± 0.07 | |
| B | 17 ± 4 | 380 ± 50 | 4.65 ± 0.12 | 20 |
From Burrows et al. models and M:
| Component and assumed age | Mass, MJup | Teff, K | log g, cm/s2 | P, yr |
| A | 11.1 ± 0.7 | 479 ± 20 | 4.37 ± 0.03 | |
| B | 7.6 ± 0.6 | 386 ± 15 | 4.19 ± 0.04 | 34 |
| A | >25 | >483 | >4.85 | |
| B | 18.8 ± 1.3 | 407 ± 15 | 4.69 ± 0.03 | <22 |
The adopted surface temperature of B is 370 ± 40 K, and adopted mass is 6-15 MJup.
Luminosity
At the time of its discovery, CFBDSIR 1458+10 B was the least luminous brown dwarf known.CFBDSIR 1458+10 bolometric luminosity estimates
| Source | Lbol/L⊙ | Lbol/L⊙ | Ref. |
| Liu et al. | 10−6.02 ± 0.14 | 10−6.74 ± 0.19 | |
| Liu et al. | 10−5.72 ± 0.13 | 10−6.53 ± 0.13 |