The Queen's clusters
Cassiopeia the Queen is the highlight constellation of our first star map. Easily recognized by its W or M shape, many of the celestial targets in this area are open star clusters within Cassiopeia's boundaries.
A notable sight outside Cassiopeia is Kemble's Cascade (NGC 1502), which glows at magnitude 5.7 in Camelopardalis the Giraffe. This chance alignment of stars (it's not a true star cluster) first was described by Franciscan amateur astronomer Father Lucian Kemble (1922–1999), who found it while scanning the sky with binoculars.
Binoculars that yield 15x reveal a dozen stars in a 2.5°-long chain. A small telescope shows 20 stars brighter than 11th magnitude, and with an 8-inch or larger scope, nearly 50 stars pop into view.
If you're new to observing, don't miss the Double Cluster (NGC 869 and NGC 884) in Perseus, which lies just to the southeast of Cassiopeia. You can see this bright pair of open clusters with naked eyes, but it's even better through binoculars. A telescope/eyepiece combination that magnifies 40x to 60x allows you to study pairs, triplets, and chains of stars within the clusters.
Two Messier objects inhabit Cassiopeia. M103 lies 1° east of Delta Cassiopeiae, which is the left bottom star of the prominent W shape marking the Queen's throne. A 6-inch scope reveals three dozen stars grouped in a triangular area 5' across.
Draw a line from Alpha through Beta Cassiopeiae and extend it an equal distance to find M52 (Map 3). Through an 8-inch scope, you'll see 75 stars clumped in various patterns. M52 lies on the edge of the Milky Way, so its stars aren't lost among the background points of light. Also on Map 3, find the Bubble Nebula (NGC 7635). This object looks best through a 12-inch or larger telescope at a dark site. An 8-inch scope reveals a short arc of gas, but that's about it.
One more open cluster you shouldn't miss is the Owl Cluster (NGC 457), which lies less than 3° south of Delta Cassiopeiae. Even a 4-inch scope will show this cluster's two "wings." The eastern wing is a line of four bright stars, and the western wing comprises two pairs of stars arranged in a long rectangle.
You can find the bright spiral galaxy NGC 2403 in Camelopardalis. Of course, in astronomy, "bright" is a relative term, but this galaxy makes the "top 100" brightest galaxies visible from Earth. Through a 6-inch scope, you'll see an oval patch 7' long with a central brightening.
M52 is an open star cluster located in Cassiopeia.