Explanation: Few cosmic vistas can excite the imagination like The Great Nebula in Orion . Visible as a faint, bland celestial smudge to the naked-eye, the nearest large star-forming region sprawls across this sharp colorful telescopic image . Designated M42 in the Messier Catalog, the Orion Nebula's glowing gas and dust surrounds hot, young stars . About 40 light-years across, M42 is at the edge of an immense interstellar molecular cloud only 1,500 light-years away that lies within the same spiral arm of our Milky Way galaxy as the Sun. Including dusty bluish reflection nebula NGC 1977 , also known as the Running Man nebula at left in the frame, the natal nebulae represent only a small fraction of our galactic neighborhood's wealth of star-forming material. Within the well-studied stellar nursery, astronomers have also identified what appear to be numerous infant solar systems .