Canes Venatici, the constellation of the Hunting Dogs, can be found just below the handle of the Big Dipper. There are many more than four galaxies to be found within this constellation's borders, but the four discussed here are bright enough to have been noticed by Charles Messier and listed in his compilation of objects. The four spiral galaxies are M51, M63, M94, M106.
M51: The Whirlpool Galaxy
M51 is also known as NGC 5194 and the Whirlpool Galaxy. The Whirlpool Galaxy has been made famous by stunning photos such as the one taken by the Hubble Space Telescope. Amateurs can find M51 by looking 3.5 degrees southeast of the last star in the Big Dipper's handle. At magnitude 8.4, the galaxy should be visible even in small telescopes if your location is not too light-polluted. Because the galaxy is situated 37 million light-years away from us, the light you are seeing is 37 million years old. The Whirlpool Galaxy has a distinctive spiral shape, and a bonus galaxy lies at the end of one of the spiral arms. The small companion, NGC 5195, is an irregular galaxy that also lies 37 million light-years away.
M63: The Sunflower Galaxy
About 6 degrees away from M51 is M63 or NGC 5055, the Sunflower Galaxy. This galaxy is similar in brightness to M51, at magnitude 8.6. M63 lies 37 million light-years from Earth, so as you can guess, it is part of a physically related group that includes M51. The central portion of the galaxy is bright, with the spiral arms fanning out from it in a circle. See if you can detect any "lumps," or star-forming regions, in the arms.
M94
M94 does not have a nickname, although its secondary catalog number is NGC 4736. M94 is about 5 degrees southwest of the Sunflower Galaxy. M94 is actually brighter than the other two galaxies, at magnitude 8.2. This face-on spiral has a very bright core, with the spiral arms being harder to detect. The distance to M94 is still a matter of debate, but calculations do put it closer to us than the Whirlpool and Sunflower Galaxies.
M106
M106, also known as NGC 4258, shines at a similar brightness to the other spiral galaxies listed here, with a magnitude of 8.3. M106 can be found more than 8 degrees west of M94. M106 is tilted so that it is neither edge-on nor face-on from our perspective. At a distance of about 23 million light-years, M106 might be the closest of the four. Try to trace the dark dust lanes in toward the galaxy's core.
Try to see how many of Canes Venatici's bright spirals you can spot on the next clear night!
Source: Celestron's The Sky software
Kelly Whitt - I have been a professional writer for more than a decade, covering many topics from science-based articles to do-it-yourself home ...
