... M57: The Ring Nebula . ... Few astronomical sights excite the imagination like the nearby stellar nursery known as the Orion Nebula. The Nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud. Curiosity: Wheels on Mars . ... Could life ever have existed on Mars? ... The Milky Trail . ... The Eagle Nebula and the Swan Nebula span this broad starscape, a telescopic view of the Sagittarius spiral arm toward the center of our Milky Way galaxy. ...