Giant 'diamond ring' sparkles 4,500 light-years away in the Cygnus constellation — Space photo of...

This striking image reveals a glittering cosmic formation dubbed a "diamond ring" — a vast, glowing structure of gas and dust appearing as a circular loop with a bright clump on one side. About 20 light-years across and located in the Cygnus X star-forming region, the ring is what's left of a bubble of ionized carbon gas, created by the intense radiation and stellar winds of a hot, massive star. But unlike typical spherical bubbles, this one expanded within a flat molecular cloud — a dense cloud of gas and dust where stars are born — before eventually rupturing and losing its symmetry. At just 400,000 years old, it's also exceptionally young — at least relative to the lifespan of massive stars.