Necklace Nebula

The Necklace Nebula is located 15,000 light-years away in the constellation Sagitta (the Arrow). New image, taken on July 2, 2011, Hubble’s Wide Field Camera 3 shows the glow of hydrogen (blue), oxygen (green), and nitrogen (red). The Necklace Nebula, is a recently discovered planetary nebula, the glowing remains of an ordinary, Sun like star. The nebula consists of a bright ring, measuring 12 trillion miles wide, dotted with dense, bright knots of gas that resemble diamonds in a necklace. A pair of stars orbiting close together produced the nebula, also called PN G054.2-03.4. About 10,000 years ago one of the aging stars ballooned to the point where it engulfed its companion star. The smaller star continued orbiting inside its larger companion, increasing the giant’s rotation rate.