HD 19993, a white bright giant star in Perseus
HD 19993 is a white bright giant star in the constellation Perseus. At 2,358 light years away, it shines at an apparent visual magnitude of 8.26.
HD 19993 (HIP 15056)
HD 19993 is a white bright giant star in the constellation Perseus. At 2,358 light years away, it shines at an apparent visual magnitude of 8.26. It is moving through the Galaxy at a speed of 23.8 km/s relative to the Sun.
Sky position: RA 3h 14.0m, Dec +37° 40.4'
Common designations: HD 19993, HIP 15056, Gaia DR3 139323074022561024
HD 19993 has the spectral type A7/A8IIe. A-type stars are white stars with surface temperatures of roughly 7,500 to 10,000 K. Their spectra are dominated by strong hydrogen lines, and many of them rotate rapidly. Its luminosity class II marks it as a bright giant, more luminous than ordinary giants.
How to find HD 19993 in the sky
HD 19993 lies in Perseus. With a declination of +37° 40.4', it is visible from the entire Northern Hemisphere and from the Southern Hemisphere down to about latitude 52° S. Observers poleward of latitude 52° N see it as circumpolar: it never sets. It is just beyond naked-eye visibility; binoculars will show it easily. It is highest in the sky at local midnight around December, which makes the weeks around that month the best time to observe it.
Tabulated data for HD 19993
Astrometry and spectroscopy
| Right Ascension (J2000) | 48.50566424° (3h 14.0m) |
| Declination (J2000) | 37.67390063° (+37° 40.4') |
| Galactic Longitude | 151.78470763° |
| Galactic Latitude | -17.08305348° |
| Proper motion RA | 2.22 mas/yr |
| Proper motion Dec | -6.57 mas/yr |
| Parallax | 1.38 ± 0.03 mas |
| Spectral Type | A7/A8IIe |
| Radial Velocity | 1.00 km/s |
Photometry
| Band | Magnitude | Abs. Mag. |
|---|---|---|
| B | 8.77 | -0.53 |
| V | 8.26 | -1.04 |
| R | 7.90 | -1.40 |
| J | 7.00 | -2.30 |
| H | 6.80 | -2.50 |
| K | 6.70 | -2.60 |
Colour index B-V: +0.51
Derivations
- Heliocentric distance: 723.12 pc (2,358 light years) (1.9% margin of error)
- Absolute visual magnitude: -1.04
- Transverse velocity: 23.8 km/s
- Space velocity relative to the Sun: 23.8 km/s
- Galactic position (X, Y, Z): -609.1 pc, 326.8 pc, -212.4 pc
- Galactic velocity (U, V, W): -5.8 km/s, -18.0 km/s, -14.4 km/s
Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.