Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2003 May 20
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A Primordial Quasar
Drawing Credit: Wolfram Freudling et al. (STECF), ESO, ESA, NASA

Explanation: What did the first quasars look like? The nearest quasars are now known to be supermassive black holes in the centres of galaxies. Gas and dust that falls toward a quasar glows brightly, sometimes outglowing the entire home galaxy. The quasars that formed in the first billion years of the universe are more mysterious, though, with even the nature of the surrounding gas still unknown. Above, an artist's impression shows a primordial quasar as it might have been, surrounded by sheets of gas, dust, stars, and early star clusters. Exacting observations of three distant quasars now indicate emission of very specific colours of the element iron. These Hubble Space Telescope observations, which bolster recent results from the WMAP mission, indicate that a whole complete cycle of stars was born, created this iron, and died within the first few hundred million years of the universe.

Tomorrow's picture: bay watch


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