Photo of the Week for June 15, 2018
Galaxies are by far the most numerous deep-sky objects, and the deeper you go, the more you find. But even the Messier catalogue, which is heavily skewed toward the brightest celestial showpieces, lists 40 galaxies. Face-on spiral, M101, in the constellation Ursa Major is one of the finest examples. It can be found under dark skies by following a string of stars curving eastward from Mizar, the middle star in the Big Dipper’s handle.
With a good-sized telescope, you can make out M101’s main spiral arms, but the finest details only show up in photographs, like this one by Raphaël Dubuc. Among the details in this image are several additional galaxies—all distant and faint. The most conspicuous of these is NGC5473, at lower left. (North is to the left in this 1.3-degree wide image.)
Raphaël captured this M101 portrait from a dark-sky location in Saint-Camille, Quebec. He used an Explore Scientific 127mm, f/7.5 ED refractor and a modified Canon EOS Rebel T3i DSLR camera equipped with a Astrodon IR/UV cut filter. Total exposure was 3¾ hours.
