Image Credit: NASA, Donald Walter (South Carolina State University), Paul
Scowen and Brian Moore (Arizona State University)
An Expanding Bubble in Space
"A star 40 times more massive than our sun is blowing a
giant bubble of material into space. In this colorful picture, the Hubble
Telescope captured a glimpse of the expanding bubble, dubbed the Bubble Nebula
(NGC 7635). The beefy star [lower center] is embedded in the bright blue
bubble. The stellar powerhouse is so hot that it is quickly shedding material
into space. The dense gas surrounding the star is shaping the castoff material
into a bubble. The bubble's surface is not smooth like a soap bubble's. Its
rippled appearance is due to encounters with gases of different thickness. The
nebula is 6 light-years wide and is expanding at 4 million miles per hour (7
million kilometers per hour). The nebula is 7,100 light-years from Earth in the
constellation Cassiopeia."