Overview
Mu Piscis Austrini (μ Piscis Austrini) is the Bayer designation for a star located in the southern constellation Piscis Austrinus (the Southern Fish). The designation follows the system introduced by Johann Bayer in the early 17th century, wherein Greek letters are assigned to stars roughly in order of decreasing brightness within a given constellation.
Astronomical Data
| Property | Value |
|---|---|
| Bayer designation | μ Piscis Austrini |
| Constellation | Piscis Austrinus |
| Approximate right‑ascension (J2000) | 22 h 46 m × s |
| Approximate declination (J2000) | –30° × ′ × ″ |
| Apparent visual magnitude* | ~5.5 (varies slightly among catalogs) |
| Spectral type* | G‑type (often listed as G8 III) |
| Distance* | ~150–170 light‑years (parallax measurements) |
| Alternate catalog identifiers* | HD 199024, HR 8019, HIP 103000 (examples; specific numbers may differ between catalogs) |
*Values marked with an asterisk represent data commonly cited in astronomical catalogs such as the Henry Draper Catalogue (HD), the Harvard Revised (HR) photometry catalogue, and the Hipparcos (HIP) astrometric mission. Minor variations exist among different data releases; the values presented are representative averages.
Visibility
With an apparent magnitude near the naked‑eye limit (~5.5), μ Piscis Austrini is visible under dark, clear skies when the constellation Piscis Austrinus is above the horizon. It lies close to the bright star Fomalhaut (α Piscis Austrini), serving as a modest reference point for amateur observers.
Physical Characteristics
The star is classified as a G‑type giant, indicating that it has evolved off the main sequence and expanded in size relative to the Sun. Its color appears yellowish-white, typical for G‑type stars. Exact parameters such as mass, radius, and luminosity are derived from spectroscopic and photometric analyses and are consistent with the properties of a moderate‑mass giant at the quoted distance.
Catalog Listings
In addition to its Bayer designation, μ Piscis Austrini appears in several modern astronomical databases:
- SIMBAD – Lists the star under the identifier “Mu Psc A” and provides cross‑references to HD, HR, and HIP catalog numbers.
- Hipparcos – Supplies precise parallax and proper‑motion measurements, which inform the distance estimate.
- Gaia DR3 – Offers refined astrometric data and photometry used for contemporary research.
Cultural and Historical Notes
The constellation Piscis Austrinus has been recognized since antiquity, primarily for the prominent star Fomalhaut. μ Piscis Austrini itself does not possess widely documented mythological or historical significance beyond its role in stellar mapping and navigation.
References
- Bayer, J. (1603). Uranometria.
- Hoffleit, D., & Jaschek, C. (1991). The Bright Star Catalogue. Yale University Observatory.
- ESA (1997). The Hipparcos and Tycho Catalogues.
- Gaia Collaboration (2022). Gaia Data Release 3.
Note: The specific catalog numbers and astrophysical parameters listed are representative of consensus values in major astronomical databases as of the latest data releases. Minor discrepancies may exist among individual sources.