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Mostly Mute Monday: Lifting The Cosmic Veil

“Thousands of years ago, a massive star near the end of its life exploded in a type II supernova, leaving behind a black hole at its center and sending its outer layers across the surrounding space. Some 1,500 light years away and 5,000–8,000 years later, that debris is 90 light years across. While the entire structure — the Cygnus Loop — is visible in the radio, infrared, ultraviolet (atop) and X-ray, the brightest visible feature is on the western edge: the Western Veil (or Witch’s Broom) nebula.”

Every century or so, possibly even more frequently, a supernova goes off somewhere in the Milky Way galaxy. While the explosion itself is only visible for a few months, the remnant sticks around for many thousands of years. Despite the thinness of the bubble walls — just one part in 50,000 of the remnant’s radius — occasionally a fortuitous alignment allows various knotty wisps and tendrils to be seen by our own eyes where the remnant is edge-on to us. Hubble imaging reveals tremendous details, including the science that the fast interior gas could travel from the Earth to the Moon in just 15 minutes!