In the famous photo "Pale Blue Dot" of the Earth from outside the solar system, one can see "bands" of colour around the Earth. What causes these bands? Is that an optical illusion? Does the band in which Earth is found describe the Earth's orbit? What are the other coloured bands? What gives them their colour? Here is the photo for reference: http://upload.wikimedia.org/wikipedia/commons/7/73/Pale_Blue_Dot.png Thanks in advance.