Pi 1 Ursa Minoris – RA: 15h 29m Dec: +80° 27′ MG: 6.6, 7.3 Sep: 31.7″ PA: 78 Spectral Type: G0, G8 subgiants Distance: 71 light years
Hmmm . . . I should be able to say something more about this easy double than that it’s a triangle inside a triangle – afterall, wherever you find three stars you can find a triangle of sorts. But John has been threatening lately to find doubles inside Ursa Minor and when he got distracted by other things, I decided I would take a look. Guess what? there are slim pickings here – especially for a 60mm. Sissy Haas lists only six doubles in Ursa Minor and uses a 60mm on only two, one being Polaris. Polaris, of course, is an exception, but it’s a challenge object for a 60mm, not, in my book, a “60mm jewell,” though it certainly is a gem in a larger scope.
Pi 1 is not a challenge. You should be able to split this little dude with anything – even a telescope you got as a prize in a Crackerjack box! And in a 60mm, it’s actually quite satisfying. Hey, I’m going to call it a very subtle violet and green, though I suspect others see it as white and, uh, sort of white. (Yep – that’s what Haas says, though it’s spectral class might suggest a bit of yellow. Maybe “sort of white” is right.)
It’s also in a kind of fun area to explore. Start at Zeta – that’s the fourth magnitude star that anchors the cup of the Little Dipper to the handle, then draw a mental line northward to the next star in the handle, Epsilon. Half way between these two, and a bit to the west, is a nice grouping of stars in the 6th-8th magnitude range. (Careful – there’s a nice group of stars to the east also.) Part of the Pi group includes a triangle of 7th magnitude stars that fits nicely inside the 2 degree field of my 32mm Plossl when used on the 60mm Unitron (28X). And inside this triangle is a second, smaller triangle of 7th magnitude stars and this one is equilateral with its southern most corner being the double. But you don’t have to figure out which corner is to the south – just look for the double. The stars are pretty closely matched (6.6 and 7.3) and split by 32 seconds – a bit more than Albireo!
Wikipedia says this pair also has an 11th magnitude companion, 135″ away. Didn’t see it. Well – didn’t look for it. Maybe another time.
Bet this field would make a nice sight in the 20X80 binos – have to give that a try!