... The Cat's Eye Nebula . ... The USNO Millennium Time Ball . ... Spanning over 25,000 light-years, comparable to the distance from the Sun to the center of our own Milky Way galaxy, a cosmic jet seen in X-rays blasts from the center of Centaurus A. Only 10 million light-years away, Centaurus A is a giant elliptical galaxy - the closest active galaxy to Earth. In the Heart of the Tarantula Nebula . ... Neptune is the eighth most distant planet from the Sun, thirty times the Earth-Sun distance. ...