70 Ophiuchi

Starbox begin
name=70 Ophiuchi Starbox observe
epoch=J2000
constell=Ophiuchus
ra=18h 05m 27.3s
dec=-02° 30' 00"
appmag_v=4.02/6.01 Starbox character
class=K0 V/K5 Ve
b-v=0.78/?
u-b=0.57/?
variable=None/Suspected Starbox astrometry
radial_v=-6.9
prop_mo_ra=124.56
prop_mo_dec=-962.66
parallax=195.96
p_error=0.87
absmag_v=5.48/7.51 Starbox visbin
name=Gl 702 B
period=88.3
axis=4.56
eccentricity=0.495
inclination=120.8
node=13.2
periastron=301.4 Starbox detail
age=?
metal=
mass=0.92/0.70
radius=0.89/0.73
gravity=4.5cite journal
author=Morell, O.; Kallander, D.; Butcher, H. R
title=The age of the Galaxy from thorium in G dwarfs, a re-analysis
journal=Astronomy and Astrophysics | year=1999
volume=259 | issue=2 | pages=543–548
url=http://adsabs.harvard.edu/abs/1992A&A...259..543M
accessdate=2007-06-05 ] /–
rotation=
luminosity=0.43/0.08 | temperature=5,300/–
age=0.8 × 10⁹ Starbox catalog
names=70 Oph, V2391 Oph, GJ 702, HR 6752, BD +02°3482, HD 165341, GCTP 4137.00, LHS 458/9, SAO 123107, Struve 2272, HIP 88601.

70 Ophiuchi is a binary star system 16.6 light years away from Earth. It is in the constellation Ophiuchus.

The primary star is a yellow-orange main sequence dwarf of spectral type K1, and the secondary star is an orange main sequence dwarf of spectral type K5.

In 1855, Capt. W. S. Jacob of the Madras Observatory of the East India Company claimed that the orbit of the binary showed an anomaly, and it was "highly probable" that there was a "planetary body in connexion with this system". [cite journal |last=Jacob |first=W.S. |year=1855 |title=On Certain Anomalies presented by the Binary Star 70 Ophiuchi |journal=Monthly Notices of the Royal Astronomical Society |volume=15 |pages=228] T. J. J. See made a stronger claim for the existence of a dark companion in this system in 1899, [cite journal |last=See |first=Thomas Jefferson Jackson |authorlink=Thomas Jefferson Jackson See |year=1896 |title=Researches on the Orbit of F.70 Ophiuchi, and on a Periodic Perturbation in the Motion of the System Arising from the Action of an Unseen Body |journal=The Astronomical Journal |volume=16 |pages=17 |doi=10.1086/102368] but Forest Ray Moulton soon published a paper proving that a three-body system with the specified orbital parameters would be highly unstable. [cite journal |url=http://www.shpltd.co.uk/jha.pdf |journal=Journal for the history of astronomy |title=A Career of controversy: the anomaly OF T. J. J. See |last=Sherrill |first=Thomas J. |date=1999 |volume=30 |accessdate=2007-08-27] The claims by Jacob and See have both been shown to be erroneous. [cite journal |last=Heintz |first=W.D. |year=1988 |month=June |title=The Binary Star 70 Ophiuchi Revisited |journal=Journal of the Royal Astronomical Society of Canada |volume=82 |issue=3 |url=http://adsabs.harvard.edu/abs/1988JRASC..82..140H |accessdate=2007-08-27] Jacob's claim was probably one of the first for an exoplanet based on astrometric evidence.

ee also

* 70 Ophiuchi in fiction

References

External links

* cite web
title=70 Ophiuchi | work=SolStation
url=http://www.solstation.com/stars/70ophiu2.htm
accessmonthday=24 October
accessyear=2005