Quasar 3C 273,composite image combining observations by three space telescopes. This is the quasar jet,a high-energy jet streaming out of a supermassive black hole (not seen,far left). From left to right,from high to low energy,the image shows X-rays (blue and green) seen by the Chandra X-ray Observatory (CXO),visible light (green and yellow) seen by the Hubble Space Telescope (HST),and infrared light (yellow and red) seen by the Spitzer Space Telescope (SST). Quasars are among the most energetic and brightest objects in the universe. The jet seen here is over 100,000 light years in length,comparable in size to the Milky Way galaxy |