WISEP J180026.60+013453.1 (designation is abbreviated to W1800+0134[1]) is a brown dwarf of spectral class L7.5,[1] located in constellation Ophiuchus at approximately 26 light-years from Earth.[1]

WISEP J180026.60+013453.1

Observation data Epoch 2010.22[1]      Equinox J2000[1]
Constellation	Ophiuchus
Right ascension	18h 00m 26.60s[1]
Declination	01° 34′ 53.1″[1]
Characteristics
Spectral type	L7.5[1]
Apparent magnitude (J (2MASS filter system))	14.30 ± 0.04[1]
Apparent magnitude (H (2MASS filter system))	13.12 ± 0.04[1]
Apparent magnitude (KS (2MASS filter system))	12.42 ± 0.03[1]
Astrometry
Proper motion (μ)	RA: 183.734[2] mas/yr Dec.: -384.108[2] mas/yr
Parallax (π)	128.0546 ± 0.5101 mas[2]
Distance	25.5 ± 0.1 ly (7.81 ± 0.03 pc)
Details
Mass	0.045±0.015[3] M☉
Luminosity	10−4.53 ± 0.04[3] L☉
Temperature	1430 ± 100[1] K
Rotation	9.3 hours[3]
Rotational velocity (v sin i)	13.5±0.5[3] km/s
Age	0.9±0.6[3] Gyr
Other designations
WISEP J180026.60+013453.1[1] W1800+0134[1] 2MASS J18002648+0134565[1] DENIS J180026.4+013457[1] DENIS-P J180026.4+013457[4]
Database references
SIMBAD	data

Discovery

WISEP J180026.60+013453.1 was discovered in 2011 by Gizis et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite — NASA infrared-wavelength 40 centimetres (16 in)) space telescope, which mission lasted from December 2009 to February 2011. There are also precovery identifications of this object in Two Micron All-Sky Survey (2MASS) data (observed on 2000 September 23) and in the 3rd release of the DENIS database (close in time to the 2MASS observation).[1] On 2011 June 22 Gizis et al. had conducted near-infrared spectroscopy with SpeX spectrograph, mounted on the 3 m Infrared Telescope Facility (IRTF), located at the Mauna Kea Observatory in Hawaii.[1] In 2011 Gizis et al. published a paper in The Astronomical Journal, where they presented discovery of a newfound by WISE L-type brown dwarf WISEP J180026.60+013453.1 (a single discovery, presented in the article).[1]

Physical properties

WISEP J180026.60+013453.1 has temperature 1430 ± 100 K and luminosity 10^{−4.5 ± 0.3} Solar luminosities (the estimates are based on the object's spectral class (L7.5)).[1] Mass estimates, determined from this temperature, are 0.04,[note 1] 0.05,[note 2] and 0.074[note 3] Solar masses, anyway below the hydrogen-burning limit, which implies that WISEP J180026.60+013453.1 is not a true star, but only a substellar object, that is a brown dwarf.[1]

Failed test for binarity

WISEP J180026.60+013453.1 was tested spectroscopically for L + T binarity, and the binarity was not revealed.[1] Common proper motion companions also were not found.[1]

See also

• List of star systems within 25–30 light-years
• WISE 0031-3840 (L2 pec (blue))
• WISE 0049+0441 (L9)
• WISE 0206+2640 (L9 pec (red))
• WISE 1311+3629 (L5 pec (blue))
• WISE 1348+6603 (L9)
• WISE 1647+5632 (L9 pec (red))
• WISE 1830+4542 (L9)
• WISE 2327-2730 (L9)
• WISE 0607+2429 (L8)
• WISE 0106+1518 (M8 pec)

Notes

References