A hazy nebula

This image from Hubble’s Wide Field Planetary Camera 2 showcases NGC 1501, a complex planetary nebula located in the large but faint constellation of Camelopardalis (The Giraffe). While NGC 1501's central star blasted off its outer shell long ago, it still remains very hot and luminous, although it is quite tricky for observers to spot through modest telescopes. This star has actually been the subject of many studies by astronomers due to one very unusual feature: it seems to be pulsating, varying quite significantly in brightness over a typical timescale of just half an hour. While variable stars are not unusual, it is uncommon to find one at the heart of a planetary nebula.