Ursa Major, a large northern constellation, contains perhaps the most famous "non-constellation" within itself: the asterism Big Dipper. Ursa Major is Latin for "big bear" and it shares the far northern skies with its smaller companion Ursa Minor (or "Little Dipper"), which owns the celestial north pole with its star Polaris. The Big Dipper...and the rest of Ursa Major (which is comprised of fainter stars) reaches its highest point in the sky...in the contiguous United States in the northern section at the meridian, around 10 in the evening during the month of April; the Big Dipper appears upside-down in this position. I always link it with Leo, another major springtime constellation, which is at the same celestial longitude and just south with the tiny and faint Leo Minor inserting itself between the two giants. As a kid I quickly learned the "basics" about the Big Dipper: if you set it "upright" and point its two front stars upward, they point to Polaris, while if you follow the curved path of the handle, that way ends up at the very bright Arcturus of the constellation Boötes. And the next-to-last star in the handle from the end, Mizar, is a sort of eye test, for it is really a double star that is separable by the naked eye into itself and its fainter companion Alcor. All of Ursa Major's brightest stars are in the Big Dipper, predominantly of the 2nd magnitude. That asterism has always been something that I searched out on clear twilights as the brighter stars of the night sky begin to make their presence known amid the darkening, fleeing blue. This constellation is also the site of a couple of annual meteor showers, although I've yet to observe them myself. I'm gradually getting better at using my new reflector telescope...Ursa Major has some deep-space objects worth looking at: the galaxies M81, M82, and M101...and the Owl Nebula, M97: wish me luck in finding them...
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