Changes

As a helium-burning giant star that has consumed all its [[hydrogen]] core fuel and left the main sequence, it has fully shifted to fusing [[helium]] in its core into [[carbon]] and [[oxygen]].  Eventually the star will begin to lose its mass and the gases will puff out as a[[ planetary nebula]] containing mostly hydrogen and helium, with smaller amounts of other elements.  What will be left is a [[white dwarf]] star that will gradually cool and fade over time.

As a helium-burning giant star that has consumed all its [[hydrogen]] core fuel and left the main sequence, it has fully shifted to fusing [[helium]] in its core into [[carbon]] and [[oxygen]].  Eventually the star will begin to lose its mass and the gases will puff out as a [[planetary nebula]] containing mostly hydrogen and helium, with smaller amounts of other elements.  What will be left is a [[white dwarf]] star that will gradually cool and fade over time.

There are no known substellar companions orbiting Arcturus at this time.  Any world that would have been [[terrestrial planet|Earth-like]] while Arcturus was on the main sequence would have long ago been destroyed.  For such a world to exist now with liquid water on its surface, it would need to be centered around 11 AU away, or between the orbital distances of [[Saturn]] and [[Uranus]] in our solar system.  Such a world would be extremely difficult to detect using current methods.

There are no known substellar companions orbiting Arcturus at this time.  Any world that would have been [[terrestrial planet|Earth-like]] while Arcturus was on the main sequence would have long ago been destroyed.  For such a world to exist now with liquid water on its surface, it would need to be centered around 11 AU away, or between the orbital distances of [[Saturn]] and [[Uranus]] in our solar system.  Such a world would be extremely difficult to detect using current methods.