Delta Equulei
From Wikipedia, the free encyclopedia
|
Delta Equulei |
|
| Observation data Epoch J2000 |
|
|---|---|
| Constellation (pronunciation) |
Equuleus |
| Right ascension | 21h 14m 28.8152s |
| Declination | +10° 00' 25.132"' |
| Apparent magnitude (V) | 4.49 / 5.4 |
| Characteristics | |
| Spectral type | F5V+ / G0 |
| U-B color index | -0.01 |
| B-V color index | 0.5 |
| Variable type | None |
| Astrometry | |
| Radial velocity (Rv) | -15.4 km/s |
| Proper motion (μ) | RA: 42.32 mas/yr Dec.: -303.43 mas/yr |
| Parallax (π) | 54.11 ± 0.85 mas |
| Distance | 60.3 ± 0.9 ly (18.5 ± 0.3 pc) |
| Absolute magnitude (MV) | 4.99 |
| Details | |
| Mass | 1.22 / 1.17 M☉ |
| Radius | 1.19 / 0.525 R☉ |
| Surface gravity (log g) | ? |
| Luminosity | 2.23 / 2.17 L☉ |
| Temperature | ? K |
| Metallicity | ? |
| Rotation | ? |
| Age | 1.6 - 2.8 billion years |
| Visual binary orbit | |
| Companion | Delta Equulei B |
| Period (P) | 5.7 yr |
| Semimajor axis (a) | 0.26" |
| Eccentricity (e) | 0.42 |
| Inclination (i) | 100° |
| Longitude of the node (Ω) | 23° |
| Periastron epoch (T) | 1912.77 |
| Other designations | |
|
HD 202275, GC 29697, LSPM J2114+1000, TD1 27843, del Equ, GCRV 13348, LTT 16227, TYC 1109-2583-1, 7 Equ, 2MASS J21142881+1000249, UBV 18362, STT 535AB, GJ 822.0, NLTT 50842, ADS 14773 AB, GJ 822, PLX 5107, USNO-B1.0 1000-00575815, AG+09° 2949, HIC 104858, PPM 139808, ASCC 991431, HIP 104858, ROT 3095, YZ 9 10630, BD+09° 4746, HR 8123, SAO 126643, CCDM J21145+1001AB, IDS 21096+0936 AB, SBC7 847, CSI+09 4746 2, JP11 3323.
|
|
| Database references | |
| SIMBAD | data |
Delta Equulei is the second brightest star in the constellation Equuleus. It sometimes called by the Arabic name Pherasauval, a contraction of the title Faras al-Awwal (الفرس الأول), meaning "The First Horse".
Delta Equulei is a binary star system about 60 light years away[1], with a class G0 star and a class F5 one[2]. Their combined magnitude is 4.47, and their absolute magnitude is 3.142. There is controversy as to the exact masses of the stars. One study puts the larger at 1.22 solar masses and the smaller at 1.17, while another pegs them at 1.66 and 1.593[2]. The luminosity of the larger star is calculated to be 2.23 solar, and the smaller to be 2.17[2].
[edit] References
- ^ SkyGazer, College Edition, version 3.4
- ^ a b c Delta Equulei. University of Illinois Astronomy department.
- HD 202275 -- Star. SIMBAD Astronomical Database. Retrieved on 2007-01-22.
[edit] External links
- Yale Bright Star Catalog; click on Equuleus
- http://www.alcyone-software.com/cgi-bin/search.pl?object=HR8123
- http://jumk.de/astronomie/special-stars/delta-equulei.shtml
 |
This star-related article is a stub. You can help Wikipedia by expanding it. |
 |
This binary or multiple star system–related article is a stub. You can help Wikipedia by expanding it. |
