Quasar PropertiesThe ChandraX-ray image is of the quasar PKS 1127-145, a highly luminous source of X-rays and visible light about 10 billion light years from Earth. An enormous X-ray jet extends at least a million light years from the quasar. Image is 60 arcsec on a side. RA11h 30m 7.10s Dec-14° 49' 27" in Crater. Observation date: May 28, 2000. Instrument: ACIS.More than 200,000 quasars are known, most from the Sloan Digital Sky Survey. All observed quasar spectra have redshiftsbetween 0.056 and 7.085. Applying Hubble's lawto these redshifts, it can be shown that they are between 600 millionand 28 billion light-yearsaway (in terms of proper distance). Because of the great distances to the furthest quasars and the finite velocity of light, we see them and their surrounding space as they existed in the very early universe.Most quasars are known to be farther than three billion light-years away. Although quasars appear faint when viewed from Earth, the fact that they are visible at all from so far away, is due to quasars being the most luminous objects in the known universe. The quasar that appears
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