2MASS J15404342−5101357
Red dwarf star in the constellation Norma
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2MASS J15404341−5101357 (abbreviated 2M1540) is a red dwarf of spectral type M7, located in Norma at 17.374 light-years (5.326 parsecs) from Earth.[3]
  2M1540 Location of 2M1540 in the constellation Norma | |
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Norma[1] |
| Right ascension | 15h 40m 43.536s[2] |
| Declination | −51° 01′ 35.97″[2] |
| Apparent magnitude (V) | 15.26[3] |
| Characteristics | |
| Evolutionary stage | main-sequence star[3] |
| Spectral type | M7V[3] |
| Apparent magnitude (J) | 8.96[4] |
| Astrometry | |
| Radial velocity (Rv) | 50.0[4] km/s |
| Proper motion (μ) | RA: 1949.461 mas/yr[2] Dec.: −324.789 mas/yr[2] |
| Parallax (π) | 187.7290±0.0496 mas[2] |
| Distance | 17.374 ± 0.005 ly (5.327 ± 0.001 pc) |
| Absolute bolometric magnitude (Mbol) | 12.81[3] |
| Details | |
| Mass | 0.105[5] M☉ |
| Radius | 0.122[5] R☉ |
| Luminosity | 9×10−4[5] L☉ |
| Temperature | 2621±100[3] K |
| Other designations | |
| GJ 12259,[6] 2M1540,[3] 2MASS J154043.42-510135.7, WISEA J154045.67-510139.3, UCAC4 195-119117, Gaia DR2 5985290231327158144 | |
| Database references | |
| SIMBAD | data |
Discovery
Its discovery was announced in 2014 by Kirkpatrick et al.[7] and independently by Pérez Garrido et al.[3]
Kirkpatrick and colleagues found a few thousand new high proper motion objects under the AllWISE program of study of images, taken by Wide-field Infrared Survey Explorer (WISE). 2M1540 was one of these high proper motion objects. They named it WISEA J154045.67-510139.3 and assigned it spectral type M6.[7]
Pérez Garrido and colleagues were looking for high proper motion sources in the 2MASS–WISE cross-match. They named it 2MASS J154043.42-510135.7 (2M1540 for short) and classified it as an M7.0±0.5 dwarf.[3]
Since the trigonometric distance of 2M1540 agreed with its spectrophotometric distances, computed for a single object, it was concluded that it is not an equal-mass binary.[3]