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Midsummer's Dream Galaxies
Garching, Germany (SPX) Aug 15, 2005 How does the Galaxy in which we live look like? It is almost certain that we will never be able to send a probe out of our Milky Way to take a snapshot, in the same way as the first satellites could do to give us striking images of planet Earth. But astronomers do not need this to imagine what our bigger home resembles. And they have a pretty good idea of it. The Milky Way with its several hundreds of billion stars is thought to be a relatively flat disc - 100,000 light-year across - with a central bulge lying in the direction of the constellation Sagittarius (The Archer) and six spiral arms. The Milky Way has most probably also a central bar made of young, bright stars. If we can't take pictures of the Milky Way, we may photograph others galaxies which astronomers think look similar to it. The two galaxies presented here are just two magnificient examples of barred spiral galaxies. One - Messier 83 - is seen face-on, and the other - NGC 4565 - appears edge-on. Together, they give us a nice idea of how the Milky Way may appear from outer space. These images are based on data obtained with the twin FORS1 and FORS2 (FOcal Reducer and Spectrograph) instruments attached to two ESO's 8.2-m Unit Telescopes of the Very Large Telescope Array located on Cerro Paranal. The data were extracted from the ESO Science Archive Facility, which contains approximately 50 Terabytes of scientific data and is, since April 1, 2005, open to the worldwide community. These invaluable data have already led to the publication of more than 1000 scientific papers. They also contains many nice examples of beautiful astronomical objects which could be the theme of as many midsummer's dreams.
NGC 4565 The first galaxy pictured here is NGC 4565, which for obvious reasons is also called the Needle Galaxy. First spotted in 1785 by Uranus' discoverer, Sir William Herschel (1738-1822), this is one of the most famous example of an edge-on spiral galaxy and is located some 30 million light-years away in the constellation Coma Berenices (Berenice's Hair). It displays a bright yellowish central bulge that juts out above most impressive dust lanes.
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