The Incredible Expanding Cats Eye . ... As this animation blinks between two Hubble Space Telescope images of NGC 6543 - the first from 1994 and the second from 1997 - the intricate filaments of this nebula are seen to shift. ... In fact, combined with other data , this nebula's detectable shift over a three year period allows the expansion age of its bright inner shells to be estimated at only around 1,000 years while its distance can be gauged at about 3,000 light-years. ...