Mosaic of Orion's belt and scabbard

Mosaic of Orion's belt and scabbard

by Rob Gendler

This Rob Gendler mosaic photo shows that the bright nebula is a small part of a much larger (and mostly dark) system of clouds that in turn form one of our galaxy's spiral arms. Density waves moving across the galactic disk compress material to form stars which in turn light up their surroundings. Two nebulae featured in the film appear in this wide-angle mosaic—the Orion Nebula to the right, and the dark Horsehead Nebula at lower left. For scale, the bright "blossom" of the Orion Nebula measures thirty light years across.