I gotta go with chromatic aberration, which is what causes things to "halo" with blue or green on one side, and red on the other. It's easy to see,
especially if you have glasses, by looking through a lens with the lens at an angle, and then stare at something with sharp contrast to the
background. Here's an example.
And
here is a site that explains the concept better than I can.
In the event of your photo, you have an object obviously reflecting light from somewhere, creating a bright spot against a dark background (high
contrast), and it is halo'd on one side by a reddish-brown, and on the other side by a blue color.
This is further supported by the fact you aren't using your own telescope, but rather Google Sky, which, like Google Streets, is more concerned with
covering a wide area than actual sharp detail. Google probably used a wide-angle lens which would almost certainly cause chromatic aberrations on
occasion.
It is absolutely not an extra-solar planet. I realize you really want to believe it is, but, as others in this thread have already stated: physics and
science has repeatedly shown extrasolar planets are not visible to us with the visible spectrum of light. They are revealed through gavitic anomalies,
light wobbles, and measuring the gasses coming from another system. They certainly wouldn't appear with Google Sky, which is like trying to find a
planet with a poster of the night sky and a magnifying glass.
Further, don't make the mistake of thinking that reflective or light-emitting objects exist within the same general sphere of distance from the
Earth. Two objects on opposite sides of the sky from one another might actually be closer than two objects appearing right next to each other.
My guess, from the shadow, and the extreme change in position in the sky (unless there's been a significant seasonal change), is that you probably
found a planet local to our system. Probably Jupiter (which was also suggested earlier). Planets move much more swiftly and erratically through the
sky over a short period of time.
[edit on 6/4/2008 by thelibra]