Editing Arcturus (section)

===Search for planets===
[[Hipparcos]] satellite [[astrometry]] suggested that Arcturus is a [[binary star]], with the companion about twenty times dimmer than the primary and orbiting close enough to be at the very limits of humans' current ability to make it out. Recent results remain inconclusive, but do support the marginal ''Hipparcos'' detection of a binary companion.<ref name=verhoelst2005/>

In 1993, radial velocity measurements of Aldebaran, Arcturus and Pollux showed that Arcturus exhibited a long-period radial velocity oscillation, which could be interpreted as a ''substellar companion''. This [[substellar object]] would be nearly 12&nbsp;times the [[mass of Jupiter]] and be located roughly at the same orbital distance from Arcturus as the Earth is from the Sun, at 1.1&nbsp;[[astronomical unit]]s. However, all three stars surveyed showed similar oscillations yielding similar companion masses, and the authors concluded that the variation was likely to be intrinsic to the star rather than due to the gravitational effect of a companion. So far no substellar companion has been confirmed.<ref name=Kgiants/>
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{{PlanetboxOrbit begin}}
{{PlanetboxOrbit hypothetical
| exoplanet = [[Arcturus b|b]]
| mass = 11.7
| period = 233
| semimajor = 1.1
| eccentricity = 0.147
}}
{{PlanetboxOrbit end}}
Put the starbox in once a planet has been confirmed, if it is a planet and not a brown dwarf.-->