Gliese 687
Gliese 687, or GJ 687 (Gliese–Jahreiß 687) is a red dwarf in the constellation Draco. This is one of the closest stars to the Sun and lies at an approximate distance of less than 15 light years. Even though it is close by, it has a magnitude of about 9, so it can only be seen through a moderately sized telescope. Gliese 687 has a high proper motion, advancing 1.304 arcseconds per year across the sky. It has a net relative velocity of about 39 km/s. It is known to have a Neptune-mass planet. Old books and articles refer to it as Argelander Oeltzen 17415.
Gliese 687 is the small orange star located in the center of the above image. | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Draco |
| Right ascension | 17h 36m 25.8999s |
| Declination | +68° 20′ 20.909″ |
| Apparent magnitude (V) | 9.15 |
| Characteristics | |
| Spectral type | M3.5 V |
| U−B color index | 1.06 |
| B−V color index | 1.49 |
| Astrometry | |
| Radial velocity (Rv) | –23.2 km/s |
| Proper motion (μ) | RA: –320.47 mas/yr Dec.: –1269.55 mas/yr |
| Parallax (π) | 219.7898 ± 0.0210 mas |
| Distance | 14.839 ± 0.001 ly (4.5498 ± 0.0004 pc) |
| Absolute magnitude (MV) | 10.87 |
| Details | |
| Mass | 0.401 ± 0.040 M☉ |
| Radius | 0.492 ± 0.038 R☉ |
| Luminosity | 0.0213 ± 0.00023 L☉ |
| Surface gravity (log g) | 4.66 cgs |
| Temperature | 3,095 ± 107 K |
| Metallicity [Fe/H] | +0.11 ± 0.20 dex |
| Rotational velocity (v sin i) | <2.8 km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Gliese 687 Location of Gliese 687 in the constellation Draco | |
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