AT Microscopii
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Microscopium |
| Right ascension | 20h 41m 51.15925s |
| Declination | −32° 26′ 06.8283″ |
| Apparent magnitude (V) | 11.0/11.1 |
| Characteristics | |
| Spectral type | M4 Ve + M4.5e |
| U−B color index | +0.91 |
| B−V color index | +1.58 |
| Variable type | Flare star |
| Astrometry | |
| Radial velocity (Rv) | 4.5 km/s |
| Proper motion (μ) | RA: +270.45 mas/yr Dec.: –365.60 mas/yr |
| Parallax (π) | 93.50±3.67 mas |
| Distance | 35 ± 1 ly (10.7 ± 0.4 pc) |
| Orbit | |
| Period (P) | 141.39 yr |
| Semi-major axis (a) | 2.616″ |
| Eccentricity (e) | 0.607 |
| Inclination (i) | 148.4° |
| Longitude of the node (Ω) | 82.6° |
| Periastron epoch (T) | 2035.10 |
| Argument of periastron (ω) (secondary) | 54.6° |
| Details | |
| AT Mic A | |
| Mass | 0.27+0.04 −0.09 M☉ |
| Radius | 0.41 R☉ |
| Luminosity | 0.036 L☉ |
| Temperature | 3,150 K |
| Age | 12+8 −4 Myr |
| AT Mic B | |
| Mass | 0.25+0.04 −0.09 M☉ |
| Radius | 0.37 R☉ |
| Luminosity | 0.033 L☉ |
| Temperature | 3150 K |
| Other designations | |
| AT Mic, CD−32°16135, GJ 799, HD 196982, HIP 102141, SAO 212355, WDS J20452-3120BC | |
| Database references | |
| SIMBAD | data |
| ARICNS | A |
| B | |
AT Microscopii is a binary star system located at a distance of 35 ly (11 pc) from the Sun in the constellation of Microscopium. Both members are flare stars, meaning they are red dwarf stars that undergo random eruptions that increase their brightness. This pair lies physically near the red dwarf star AU Microscopii, which may mean they form a wide triple star system.