Faint galaxies in Ursa Major
The pan of the Big Dipper, as shown in Sky&Telescope’s Pocket Sky Atlas
This time round I’m going to steer away from the easier targets I usually mention (planets, Messier and Caldwell objects, for example), and concentrate instead on some more challenging targets.
I was listening to an astronomy podcast recently (@Awesomeastropod), and, when the discussion swung round to the subject of faint galaxies in and around Ursa Major, I was reminded of a ‘challenge’ I read about on the CloudyNights.com forum, referred to as the ‘9 in the pan’. US astronomy magazine Sky & Telescope’s Pocket Sky Atlas (a must-have, in my opinion) shows nine galaxies in the pan, or bowl, of the Big Dipper. All are in excess of magnitude 11, and thus are right at the limit of what UK skies and a fairly large telescope (10 inch reflector, for example), will allow you to see.
I know I’ve tried for these in the past, and when I consulted my journal, discovered that it was on the 26th of February time last year (three ‘definite’ and one ‘pretty sure’). With Ursa Major ideally placed in the evening sky at the moment, I’d say it’s time to have another go at the ‘nine’.
If you don’t have a copy of the Pocket Sky Atlas the NGC numbers are: 3982, 3998, 3898, 3780, 3619, 3613, 3610, 3642 and 3690.
As well as these nine, there are several other targets in the area. Just to the left of a line drawn between Megrez and Dubhe are NGCs 3835, 3945, 4036 and 4041, again all in excess of mag 11. 4041 is thought to lie around 79 million light years away!
To the right of a line drawn between Merak and Phecda are NGCs 3738, 3756, 3631, 3729 and 3718. Of all the group, only the first and last mentioned have Wikipedia pages. 3738 is a dwarf galaxy about 12 million light years away, while 3718 lies 52 million light years away, and apparently owes its warped shape to the gravitational interaction between it and 3729.
Below and to the right of Phecda (the lower of the bottom stars in the pan of the Big Dipper) lies NGC 4102 and 3953 – both around 68 million light years away. From there, stretching all the way to the Coma Berenices constellation/cluster, Sky & Telescope’s Pocket Sky Atlas lists over 25 NGC galaxies.
Returning to the @Awesomeastropod podcast for a moment, one of the presenters mentioned the fact that everyone gets very excited about the Virgo galactic super cluster, which will be on view shortly in the evening skies, but all the while there’s so much to see in Ursa Major which is visible from the UK all year round. Although perhaps not as impressive for the visual astronomer as the Virgo/Coma Berenices groups, there’s in excess of 45 NGC galaxies stretching from the pan of the Big Dipper all the way to Coma Berenices (not to mention several Messier galaxies). So, if you have the scope, and suitably dark skies, and a modicum of patience, there’s a lot to explore in and around Ursa Major all year round!
The next Full Moon will be on the 11th, with the New Moon on the 26th.
Venus is spectacular in the evening skies at the moment. I had a look at the weekend and found the slim crescent entrancing (until the clouds rolled in, that is).
Jupiter is lovely and bright, unmistakeable high in the southwest before dawn.
Comets 45P/Honda-Mrkos-Pajdusakova, and 2P/Encke should be visible with binoculars and telescopes during February. The former is currently high in the east before dawn, just to the right of the star Deneb as Okab in Aquila. By the middle of the month it will be visible in the evenings (around 10PM, for example), though it’s dimming all the time. Comet 2P/Encke is currently mag 10, and so a harder target than 45P/Honda-Mrkos-Pajdusakova, and you’ll probably need a telescope to see it. It can be found just after sunset, slightly to the right of Venus.
The next stargazing session at The New Inn in Cerne Abbas is on Sunday the 26th, from 6PM.
Kevin Quinn is an amateur astronomer based in Piddletrenthide. He is the proud owner of a ten-inch reflector, a small refractor, a case of eyepieces, and a couple of pairs of binoculars. He tweets via @CerneAstro, and blogs (occasionally) via theastroguy.wordpress.com.