TW Piscis Austrini
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Observation data Epoch J2000 |
|
---|---|
Constellation (pronunciation) |
Piscis Austrinus |
Right ascension | 22h 56m 24.1s |
Declination | -31° 33′ 56″ |
Apparent magnitude (V) | 6.48 |
Characteristics | |
Spectral type | K4-5 Ve |
U-B color index | 1.02 |
B-V color index | 1.10 |
Variable type | BY Draconis |
Astrometry | |
Radial velocity (Rv) | +6 km/s |
Proper motion (μ) | RA: 330.53 mas/yr Dec.: -159.85 mas/yr |
Parallax (π) | 130.94 ± 0.92 mas |
Distance | 24.9 ± 0.2 ly (7.64 ± 0.05 pc) |
Absolute magnitude (MV) | 7.07 |
Details | |
Mass | 0.81 M☉ |
Radius | 0.76-0.85 R☉ |
Luminosity | 0.12 L☉ |
Temperature | ? K |
Metallicity | ? |
Rotation | ? |
Age | 2 × 108 years |
Other designations | |
TW Piscis Austrini is a dwarf star in the constellation Piscis Austrinus. It lies relatively close to the Sun, at an estimated distance of 24.9 light years.
The TW in the name is astronomical nomenclature for a variable star. This is a flare star of the type known as a BY Draconis variable. It varies slightly in apparent magnitude, ranging from 6.44 to 6.49 over a ten day period. While smaller than the Sun, it is relatively large for a flare star. Most flare stars are red M-type dwarfs.
TW Piscis Austrini lies within a light year of the much-brighter star Fomalhaut, and the two may be travelling companions that share a common motion through space.
[edit] External links
- ARICNS entry
- TW Piscis Austrini at SolStation.
- Alcyone ephemeris