Gliese 710
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| Observation data Epoch J2000 |
|
|---|---|
| Constellation (pronunciation) |
Serpens |
| Right ascension | 18h 19m 51s |
| Declination | -01° 56.4′ |
| Apparent magnitude (V) | 9.65-9.69(var) |
| Characteristics | |
| Spectral type | K7V |
| U-B color index | 1.23 |
| B-V color index | 1.36 |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | -24.0 km/s |
| Proper motion (μ) | RA: -130 mas/yr Dec.: -50 mas/yr |
| Parallax (π) | 51.8 ± 7.1 mas |
| Distance | approx. 63 ly (approx. 19 pc) |
| Absolute magnitude (MV) | 8.7 ± 0.3 |
| Details | |
| Mass | 0.42 M☉ |
| Radius | 0.1 R☉ |
| Luminosity | (bolometric)0.042 L☉ |
| Temperature | 4000 K |
| Metallicity | ? |
| Rotation | >14 km/s. |
| Age | ? years |
| Other designations | |
|
Gliese 710, BD-01 3474, Gl 710, Hip 89825, HD 168442, U449, Vys/McC 63, NSV 10635
|
|
Gliese 710 is a red dwarf star in the constellation Serpens Cauda, with visual magnitude 9.66 and a mass of 0.4–0.6 solar masses.
It is about 63.0 light years from Earth, but is notable because its proper motion, distance, and radial velocity[1] indicate that it will approach within 1.1 light years (70,000 AU) from Earth within 1.4 million years, based on the latest Hipparcos data. At closest approach it will be a first-magnitude star about as bright as Antares. As one can reference from the data on the right, the proper motion of this star is very small for its distance, meaning it is travelling nearly directly in our line of sight; Compare for example with Arcturus.
In a time interval of ±10 million years from the present, Gliese 710 is the star whose combination of mass and close approach distance will cause the greatest gravitational perturbation of our solar system. Specifically, it has the potential to perturb the Oort cloud enough to send a shower of comets into the inner solar system, possibly causing an impact event. However, recent dynamic models by García-Sánchez, et al. indicate that the net increase in cratering rate due to the passage of Gliese 710 will be no more than 5%. They estimate that the closest approach will happen in 1,360,000 years when the star will approach within 0.337 ± 0.177 pc (1.1 ly) of the Sun.[2]
Interestingly, the star with the second greatest perturbational effect in the past or future 10 million years was Algol, a triple star system that passed no closer than 9.8 light years, 7.3 million years ago, but with a considerably larger total mass of 5.8 solar masses. Algol (also known as the Demon Star) was traditionally considered the unluckiest star in the sky, which is reflected in its name (Al-ghol means 'the ghoul' in Arabic)
[edit] References
- ^ See also: Space velocity.
- ^ García-Sánchez, J.; Weissman, P. R.; Preston, R. A.; Jones, D. L.; Lestrade, J.-F.; Latham, D. W.; Stefanik, R. P.; Paredes, J. M. (2001). "Stellar encounters with the solar system". Astronomy and Astrophysics 379: 634–659.
[edit] Further reading
- García-Sánchez, Joan; et al. (1999). "Stellar encounters with the Oort cloud based on Hipparcos data". The Astronomical Journal 117: 1042-1055. doi:.
