PINWHEEL PERFECTION 5471 by Alan Whitman 5451 5462 5449 5461 5453 5447 5458 5450 5455 A Galaxy-Hop Around M101 BRIMMING WITH H II REGIONS The author tackled the H II regions in the spiral arms of M101, and on his first visit identified three knots. Two subsequent tours of the outer arms of the galaxy revealed a further seven knots. Take a telescopic tour of the Pinwheel Galaxy and its neighbors. 14 JUNE 2 02 0 * SK Y & TELESCOPE of my favorite articles on a stunning spiral galaxy in the far eastern reaches of Ursa Major: M101. Join me as we acquaint ourselves with this magnificent object and its surroundings. Diving into M101's Spiral Arms The June 1993 issue of Sky & Telescope featured the article "A Visual Tour of M101" by amateur astronomer Roger N. Clark, who used to observe at an excellent site in the Colorado Rockies. M101 is a spiral galaxy that displays a mixture of POSS-II / STSCI / CA LTECH / PA LO MAR OBSERVATORY I tear out many of the observing articles in Sky & Telescope to use as guides whenever a superb night might present itself, and I add them to my ever-thickening observing folder. But not every month offers a superb night at my latitude of 49° north, even though I live in the semiarid Okanagan Valley of southern British Columbia, on the drier and clearer eastern side of the Cascade Mountains. The June section of my observing folder contains several articles that I dip into often. This June will be no exception. I'll turn to some