31 Aquilae
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31 Aquilae
Observation data
Epoch J2000 Equinox J2000 |
| Constellation |
Aquila |
| Right ascension |
19h 24m 58.20027s[1] |
| Declination |
+11° 56′ 39.8862″[1] |
| Apparent magnitude (V) |
5.16[2] |
| Characteristics |
| Spectral type |
G8 IV[2] |
| U−B color index |
+0.42[3] |
| B−V color index |
+0.77[2] |
| Astrometry |
|
| Radial velocity (Rv) |
–100.5[4] km/s |
| Proper motion (μ) |
RA: +721.02[1] mas/yr
Dec.: +642.49[1] mas/yr |
| Parallax (π) |
65.89 ± 0.26[1] mas |
| Distance |
49.5 ± 0.2 ly
(15.18 ± 0.06 pc) |
|
| Details |
|
| Mass |
1.16 ± 0.07[5] M☉ |
| Radius |
1.379 ± 0.042[6] R☉ |
| Luminosity |
1.904 ± 0.045[6] L☉ |
| Surface gravity (log g) |
4.18 ± 0.03[5] |
| Temperature |
5,510 ± 90[2] K |
| Metallicity [Fe/H] |
+0.37[7] dex |
| Age |
4.5 ± 0.2[5] Gyr |
|
| Other designations |
b Aql, BD+11 3833, FK5 1503, HD 182572, GJ 759, NLTT 47763, HIP 95447, HR 7373, LFT 1477, LHS 3463, LTT 15668, NSV 11994, SAO 104807. |
| Database references |
| SIMBAD |
data |
| Data sources: |
Hipparcos Catalogue,
CCDM (2002),
Bright Star Catalogue (5th rev. ed.) |
31 Aquilae (b Aquilae) is a subgiant star in the constellation Aquila. Its apparent magnitude is 5.17. Its age is probably similar to NGC 188, the oldest open cluster known, which was calculated to be over 5 billion years. For its age, it is surprisingly metal rich, contrary to common assumptions that the oldest stars should be metal-poor.
[edit] Hunt for substellar objects
No certain substellar companion has been detected so far around 31 Aquilae. McDonald Observatory team has set limits to the presence of one or more planets [8] around 31 Aquilae with masses between 0.22 and 1.9 Jupiter masses and average separations spanning between 0.05 and 5.2 Astronomical Units.
[edit] Optical companions
[edit] References
- ^ a b c d e van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. Bibcode 2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
- ^ a b c d Malagnini, M. L.; Morossi, C. (November 1990), "Accurate absolute luminosities, effective temperatures, radii, masses and surface gravities for a selected sample of field stars", Astronomy and Astrophysics Supplement Series 85 (3): 1015–1019, Bibcode 1990A&AS...85.1015M
- ^ Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99), Bibcode 1966CoLPL...4...99J
- ^ Wielen, R. et al. (1999), Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions, Astronomisches Rechen-Institut Heidelberg, Bibcode 1999VeARI..35....1W
- ^ a b c Trevisan, M. et al. (November 2011), "Analysis of old very metal rich stars in the solar neighbourhood", Astronomy & Astrophysics 535: A42, Bibcode 2011A&A...535A..42T, doi:10.1051/0004-6361/201016056 . See Table 13.
- ^ a b Boyajian, Tabetha S. et al. (February 2012), "Stellar Diameters and Temperatures. I. Main-sequence A, F, and G Stars", The Astrophysical Journal 746 (1): 101, Bibcode 2012ApJ...746..101B, doi:10.1088/0004-637X/746/1/101 . See Table 10.
- ^ Soubiran, C. et al (2008). "Vertical distribution of Galactic disk stars. IV. AMR and AVR from clump giants". Astronomy and Astrophysics 480 (1): 91–101. Bibcode 2008A&A...480...91S. doi:10.1051/0004-6361:20078788.
- ^ Detection Limits from the McDonald Observatory Planet Search Program
[edit] External links
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In left column are stellar classes of primary members of star systems. ‡Distance error margin extends out of declared distance interval. Italic are systems possibly located within declared distance interval, but probably not.
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