Look at Orion’s sword without a telescope and the middle star is fuzzy. This is what’s there: a cavity roughly 24 light-years wide, hollowed out of a much bigger cold cloud by four young stars at its centre, the Trapezium. They’re around a million years old, which for a star is infancy, and their ultraviolet light is what makes the gas glow. The brown and red haze filling the rest of the frame is the cloud they haven’t got to yet. M43 sits just above the core with its own dark lane, and the blue reflection nebula near the top is NGC 1977, the Running Man. At 1,340 light-years this is the closest region of massive star formation to us, which is the only reason we can see any of it in this much detail.
