The Veil Nebula

These delicate threads, spread across the width of six full Moons, are the debris of a dead star. Between 10,000 and 20,000 years ago, a star some twenty times heavier than the Sun exploded. For a while, it shone brighter than Venus, visible in broad daylight.

What remains of it now drifts about 2,400 light-years away, in the constellation of Cygnus. The shock wave is still racing through space and sweeps up the gas it meets; heating it to extreme temperatures, it makes the gas glow and traces these lacy wisps, spread over nearly 120 light-years.

Each filament marks the passage of the shock wave. And the colours betray the matter itself: oxygen emits blue-green light, hydrogen red light, each with its own hue, like the gases in a neon sign.