NGC 6357: The Lobster Nebula
Why is the Lobster Nebula forming some of the most massive stars known? No one is yet sure . Cataloged as NGC 6357, the Lobster Nebula houses the open star cluster Pismis 24 near its center -- a home to unusually bright and massive stars. The overall blue glow near the inner star forming region results from the emission of ionized hydrogen gas. The surrounding nebula, featured here , holds a complex tapestry of gas, dark dust , stars still forming, and newly born stars. The intricate patterns are caused by complex interactions between interstellar winds , radiation pressures , magnetic fields , and gravity . NGC 6357 spans about 400 light years and lies about 8,000 light years away toward the constellation of the Scorpion . Free Download: 2019 APOD Calendar (v5)