M51: The Whirpool Galaxy
<p>M51, the Whirlpool Galaxy, was one of Charles Messier's original discoveries. First catalogued in 1773, M51 is the dominant member of a small group of galaxies located over 37 million lightyears away. M51 is easy to see under dark sky conditions, but it is quite sensitive to light pollution.</p> <p>The smaller galaxy, NGC5195, is sometimes referred to as "M51B", while the larger galaxy is identified as "M51A". According to current theories, the spiral structure of M51A is a result of its encounter with the smaller galaxy. The interaction of the two objects, compressed and disturbed the gas in several regions, resulting the formation of new young stars.</p>
