The violent death of a star, which may have been visible to our ancestors 8,000 years ago as a bright but short-lived new point of light in the sky, left behind a beautiful cosmic object captured in dramatic new images by the Hubble Space Telescope.
The space telescope first photographed the supernova remnant known as the Veil Nebula, a twisting, multi-colored halo of gas 2,100 light-years from earth still expanding from the original massive explosion 18 years ago.
The new images of the nebula, located in the constellation Cygnus (The Swan), were created by overlaying images captured in 1997 by Hubble's Wide Field and Planetary Camera 2 (WFPC2) with more images from the space telescope's new Wide Field Camera (WF3C).
The expanding wave of gas emitted by the supernova is now 110 light-years across, producing light as it crashes at almost a million miles per hour into cooler, denser interstellar gas, NASA says.
The newly-released Hubble images show just two light-years of the nebula's extent, on its outer limb, but the colors — red from ionized hydrogen, blue from oxygen and green from sulfur — create a dazzling cosmic display.
The section of the nebula captured by Hubble has the scientific tag NGC 6960, but is more colloquially known as the Witch's Broom Nebula.
The entire Veil Nebula, created by the explosion of a star roughly 20 times the mass of our sun, is one of the best-known supernova remnants.
Astronomers say the nebula's distinctive delicate, draped structure — the source of its name — is the result of its expanding gases hitting the walls of a cavity in the surrounding interstellar gas created by a strong stellar wind emitted by the star prior to its explosion.
The expanding shockwave of gas hitting the relatively dense walls of the cavity produces the bright filaments seen in the image, astronomers explain.
Variations in the temperatures and densities of chemicals in the walls are producing the different colors of the Veil Nebula, they say.
"Despite the nebula's complexity and distance from us, the movement of some of its delicate structures is clearly visible," the ESA says in a release on its website.