Phi-2 Ceti, a yellow-white main-sequence star in Cetus
Phi-2 Ceti is a yellow-white main-sequence star in the constellation Cetus. At 52 light years away, it shines at an apparent visual magnitude of 5.19.
Phi-2 Ceti (HIP 3909)
Phi-2 Ceti is a yellow-white main-sequence star in the constellation Cetus. At 52 light years away, it shines at an apparent visual magnitude of 5.19. It is moving through the Galaxy at a speed of 25.8 km/s relative to the Sun.
Sky position: RA 0h 50.1m, Dec -10° 38.7'
Common designations: Phi-2 Ceti, 19 Ceti, HR 235, HD 4813, HIP 3909, Gaia DR3 2473608009504466688, GJ 37
Phi-2 Ceti has the spectral type F7V. F-type stars are yellow-white stars of about 6,000 to 7,500 K, slightly hotter and more massive than the Sun. Their hydrogen lines are weaker than in A stars and metal lines become prominent. Its luminosity class V means it is a main-sequence (dwarf) star, still fusing hydrogen into helium in its core like the Sun.
How to find Phi-2 Ceti in the sky
Phi-2 Ceti lies in Cetus. With a declination of -10° 38.7', it is visible from the entire Southern Hemisphere and from the Northern Hemisphere up to about latitude 79° N. It is bright enough to see with the naked eye under dark skies. It is highest in the sky at local midnight around October, which makes the weeks around that month the best time to observe it.
Tabulated data for Phi-2 Ceti
Astrometry and spectroscopy
| Right Ascension (J2000) | 12.53162068° (0h 50.1m) |
| Declination (J2000) | -10.64432885° (-10° 38.7') |
| Galactic Longitude | 121.79647404° |
| Galactic Latitude | -73.51318512° |
| Proper motion RA | -228.03 mas/yr |
| Proper motion Dec | -229.58 mas/yr |
| Parallax | 62.80 ± 0.10 mas |
| Spectral Type | F7V |
| Radial Velocity | 8.15 km/s |
Photometry
| Band | Magnitude | Abs. Mag. |
|---|---|---|
| B | 5.69 | 4.68 |
| V | 5.19 | 4.18 |
| J | 4.41 | 3.40 |
| H | 4.01 | 3.00 |
| K | 4.01 | 3.00 |
Colour index B-V: +0.50
Derivations
- Heliocentric distance: 15.92 pc (52 light years) (0.2% margin of error)
- Absolute visual magnitude: 4.18
- Transverse velocity: 24.4 km/s
- Space velocity relative to the Sun: 25.8 km/s
- Galactic position (X, Y, Z): -2.4 pc, 3.8 pc, -15.3 pc
- Galactic velocity (U, V, W): 22.3 km/s, -2.7 km/s, -12.6 km/s
Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.