In astronomy, a green star is a white or blueish star that appears greenish in some viewing conditions (see ยง Psychology below). Under typical viewing conditions, there are no greenish stars, because the color of a star is more or less given by a black-body spectrum. However, there are a few stars that appear greenish to some observers, due to the viewing conditions, for example the optical 'illusion' that a red object can make nearby objects look greenish (and vice versa). Some multiple star systems, such as Antares, have a bright reddish or yellowish star where this contrast makes other stars in the system seem greenish.[citation needed] From Wikipedia
