... And in our Milky Way....and in our 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. Hubble has also examined massive stars closer to Earth. These include Eta Carinae Eta Carinae (η Carinae or η Car) is a highly luminous hypergiant double star. Estimates of its mass range from 100–150 times the mass of the Sun, and its luminosity is about four million times that of the Sun. , some 8,000 light-years away, which astrophysicsts speculate may be the next Milky Way star to explode as a giant supernova supernova, a massive star in the latter stages of stellar evolution that suddenly contracts and then explodes, increasing its energy output as much as a billionfold. . Using the telescope's Wide-Field/Planetary Camera, J. Jeff Hester and his colleagues at the California Institue of Technology in Pasadena photographed this bright star, its gas halo and the surrounding interstellar medium interstellar medium Content of the region between the stars, including vast, diffuse clouds of gases and minute solid particles. Such tenuous matter in the Milky Way Galaxy accounts for about 5% of its total mass. in unprecedented detail, resolving structures just a few tenths of an arc-second across. (Computer software compensated for distortions caused by Hubble's optical flaw.) The Hubble photograph reveals that a previously pictured shell of matter, observed hurling hurling, outdoor ball and stick game similar to field hockey (see hockey, field). The national pastime of Ireland, it was played for many centuries before the Gaelic Athletic Association standardized the rules in 1884. from the star in 1843, contains small clumps of matter--a strong indication, Hester says, that it has begun to fragment. The new image also shows that the shell -- about one-third of a light-year from the stellar core -- has a well-defined boundary, a feature that scientists hope may clarify how Eta Carinae expelled the mass. The Hubble Space Telescope's image also delineates a network of clumps and filaments farther out farther out Of or relating to an option contract with a later expiration date than a contract that is currently owned or being considered. For example, a contract with a May expiration date is farther out than a contract with a February expiration date of from the shell, about half a light-year from the star's center. These structures, explains Hester, stem from shock waves in regions where material from the outburst observed in 1843 has slammed into both the interstellar medium and matter from previous outbursts. The collision zones may provide clues about the history and future of this unstable star, she says. |
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