The Bubble Nebula is a small, glowing shell of gas in the constellation Cassiopeia,
created by the powerful stellar wind from a massive, hot young star at its center.
That star blows material outward, forming the delicate
“bubble” shape while surrounding clouds of hydrogen and oxygen emit light in reds and blues.
Although the nebula looks calm in an image, it is actually a dynamic, expanding structure
shaped by intense radiation and shock waves. It is expanding into uneven, lumpy clouds of
surrounding gas. Because some regions are dense and others are thin, the bubble grows faster
in certain directions and slower in others, giving it the shape of a slightly distorted sphere.

The Bubble Nebula can be thought of as a cosmic version of a soap bubble—except this
one is seven light years wide and sculpted by a star tens of thousands of times
brighter than the Sun. Its glowing colors come from energized gases, and its round form
stands out beautifully against the dense star fields of Cassiopeia.

Image Data:
Telescope: Planewave CDK 14"
Camera: ZWO ASI6200
Exposure: 345 minutes each of hydrogen-alpha and Oxygen-III, RGB 18 minutes each