The Pistol Nebula surrounds one of the most massive stars known, the Pistol Star

Pistol Star

The Pistol Star is a blue hypergiant and is one of the most luminous known stars in the Milky Way Galaxy.It is one of many massive young stars in the Quintuplet cluster in the Galactic Center region....

. Both are located 25,000 light years away from Earth, near the center of the Milky Way galaxy. The nebula contains approximately 10 solar mass

Solar mass

The solar mass , , is a standard unit of mass in astronomy, used to indicate the masses of other stars and galaxies...

es worth of ionized gas that was ejected by the star several thousand years ago. The nebula was named in the 1980s for its shape as seen in low resolution images that were available at the time. The pistol star, a luminous blue variable

Luminous blue variable

Luminous blue variables, also known as S Doradus variables, are very bright, blue, hypergiant variable stars named after S Doradus, the brightest star of the Large Magellanic Cloud. They exhibit long, slow changes in brightness, punctuated by occasional outbursts in brightness during substantial...

is 1.7 million times as bright as the Sun, and 120-200 times as massive.