Behind the Milky Way: unveiling a galaxy.The fuzzy arc of the Milky Way Milky Way, the galaxy of which the sun and solar system are a part, seen as a broad band of light arching across the night sky from horizon to horizon; if not blocked by the horizon, it would be seen as a circle around the entire sky. has fascinated skywatchers for millennia. But this patchy collection of gas and dust -- the disk of our galaxy -- takes up some 20 percent of the sky, blocking from view a sizable chunk of the universe. What lurks behind the disk of the Milky Way? A new study supports the notion that the hidden region teems with galaxies, some of them in our own cosmic backyard. An international team of astronomers began its work by using a radio telescope to search for emissions from atomic hydrogen gas located outside -- but in the same part of the sky as -- our galaxy. Such radio emissions can penetrate the Milky Way's veil of gas and dust -- if the extragalactic ex·tra·ga·lac·tic adj. Located or originating beyond the Milky Way. Adj. 1. extragalactic - outside or beyond a galaxy; "extragalactic nebula" gas moves at a different speed than gas in the galaxy. The team now reports that it has found a previously unknown galaxy, a spiral neighbor only 10 million light-years from the Milky Way. Astronomers dubbed the galaxy Dwingeloo 1 in honor of the 25-meter radio telescope at Dwingeloo, the Netherlands, through which it was first viewed. The galaxy probably belongs to a nearby group of galaxies that includes IC342, Maffei 1, and Maffei 2. Unlike another nearby galaxy recently discovered behind our own (SN: 4/9/94, p.228), Dwingeloo 1 lies too far away for the Milky Way to devour it. But it does seem to reside close enough to affect the motion of the Milky Way and its family of galaxies, known as the Local Group. Ofer Lahav of the University of Cambridge in England and his colleagues, including Harry C. Ferguson of the Space Telescope Science Institute The Space Telescope Science Institute (STScI) is the science operations center for the Hubble Space Telescope (HST; in orbit since 1990) and for the James Webb Space Telescope (JWST; scheduled to be launched in 2013). in Baltimore, detail their work in the Nov. 3 NATURE. The group found that the location of the newfound galaxy coincides with a dim, unidentified feature on photographic plates taken as part of the Palomar Sky Survey The Palomar Sky Survey is a complete photographic survey of the whole sky which was made by the large Schmidt camera of the newly built Mount Palomar observatory in the 1950's. . Lahav and his coworkers then confirmed their finding with the Westerbork radio telescope in Hooghalen, the Netherlands. They also imaged the galaxy in visible light with the William Herschel Telescope This article is about the telescope on the Canary Islands. For the future ESA space telescope, see Herschel Space Observatory. “WHT” redirects here. For the cable TV company, see Wometco Home Theater. in the Canary Islands, Spain. In a commentary accompanying the NATURE report, David Burstein of Arizona State University Arizona State University, at Tempe; coeducational; opened 1886 as a normal school, became 1925 Tempe State Teachers College, renamed 1945 Arizona State College at Tempe. Its present name was adopted in 1958. in Tempe notes that the new discovery may rank among the first of many galaxies found behind the murk murk also mirk n. Partial or total darkness; gloom. adj. Archaic Partially or totally dark; gloomy. [Middle English mirke, from Old Norse myrkr of the Milky Way. "It is encouraging to see the veil of the Milky Way slowly lifted, and we await with anticipation the full unveiling," he writes. |
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