NGC 6302 is a bipolar type planetary nebula in the constellation Scorpius. The structure in this planetary nebula is among the most complex ever seen in any planetary nebulae. The spectrum of Butterfly Nebula shows that its central star is one of the hottest stars known, with a surface temperature in excess of 250,000 degrees Celsius. This implies that the star from which it formed must have been very large in order to become this hot.