Barred Spiral Galaxy NGC 6217

Explanation: Many spiral galaxies have bars across their centers. Even our own Milky Way Galaxy is thought to have a modest central bar. Prominently barred spiral galaxy NGC 6217, featured here, was captured in spectacular detail in this image taken by the Advanced Camera for Surveys on the orbiting Hubble Space Telescope in 2009. Visible are dark filamentary dust lanes, young clusters of bright blue stars, red emission nebulas of glowing hydrogen gas, a long bar of stars across the center, and a bright active nucleus that likely houses a supermassive black hole. Light takes about 60 million years to reach us from NGC 6217, which spans about 30,000 light years across and can be found toward the constellation of the Little Bear (Ursa Minor).

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What did the first quasars look like? The black hole in the center of the active galaxies is the nearest quasar. Gas and dust that falls toward a quasar glows bright, sometimes outglowing the entire home galaxy. The quasars that formed in the first billion years of the universe are more mysterious. Recent data has enabled an artist's impression of an early-universe quasar, centered on a massive black hole surrounded by sheets of gas and an accretion disk, and expelling a powerful jet. Quasars give us unique information about the early and intervening universe. The universe was only a few percent of its current age when the oldest quasars were seen.