A star in the constellation Cassiopeia is blowing the giant bubble seen in this newly released Hubble Space Telescope image. Known as the Bubble Nebula, it's the result of a strong wind from a star that is 10 to 20 times as massive as the Sun. The stream of particles sweeps up interstellar gas and dust around the star, forming the bubble. Ultraviolet radiation from the star itself, which is near the top left edge of the bubble, causes the bubble to glow. The wind also carves away at dense blobs of gas and dust that stretch to the upper left of the star. The nebula is about 8,000 light-years from Earth. [NASA/ESA/Hubble Heritage Team]