Bubble Nebula – Celestron Origin
It sits in the constellation Cassiopeia.
You can find it about 7,100 to 7,500 light years from Earth. It lives inside a busy star forming region of the Milky Way.
Its official catalog name is NGC 7635.
Astronomers discovered it in 1787. The nebula has been photographed many times since then because of its unusual shape.
A massive young star created the bubble shape.
This star is about 40 times more massive than our Sun. Its strong stellar winds push surrounding gas outward which forms the round shell we call the bubble.
The bubble is roughly seven light years across.
The structure looks delicate although it is enormous. Light needs seven years to travel from one side of the bubble to the other.
The glowing colors come from energized gas.
The star floods the gas with radiation. This radiation makes the gas glow in shades of red, blue, and green depending on the elements involved.
It keeps expanding over time.
The bubble grows because the powerful winds continue to force the gas outward. The expansion is slow on a human timeline but obvious over long astronomical periods.
It sits inside a much larger cloud.
The bubble is only a small part of a wider molecular cloud. That cloud holds dust and gas that fuel new stars.
