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ving
27-07-2007, 02:50 PM
Seeing Double ~ Musca

Captain cook sailed in his great ship Argo Navis to the southern land (represented by crux of course) and found there to be too many flies (Musca)... ok so I made it up, but it sheer coincidence that next to the constellation that represents Australia is Musca the fly?
Being 77th in size among constellations means that Musca I not particularly big. It was introduced in the 17th century by Johann Bayer as Apis - the bee to then be changed in 1752 by Nicolas Louis de Lacaille to Musca Australis which has now been shortened to just plain Musca.
If you have learned anything from my "seeing double" logs it should be that good things happen in twos. Musca is no exception and has 2 nice (if somewhat faint and partly obscured by dust) globular clusters NGC 4833 and 4872. There are also a couple of planetary nebula here worth looking at. While we are talking about twos, in 1991 a really interesting binary was discovered here, we are talking about the soft X-ray transient Nova Muscae a black hole and a star! But enough of this, on to the binaries!

1. Hj4550 7.63/8.74, 13.5": lets start with an easy but beautiful split. Nestled not far from Beta Mus this is a nice pair of white and reddy/orange.

2. Hj4522 7.88/8.68, 12.7": this could almost be a twin to the previous one tho the red star is not red here but yellow. Still a fine sight though.

3. Hj4515 8.80/10.90, 13.2": could it be! Do we have triplets? Dimmer that the previous 2 doubles this couple is of similar colour, that being white and red though it’s a deep red.

4. Hds1763 9.33/9.34, 22.5": this pair is an easy split too in an asterism forming one point. Both stars are almost identical in both brightness and colour.

5. Hdo222 6.10/12, 34.6": here you go a challenge for small scopes. Its not that these are close by any means but the secondary star is quite a dim one. The primary is a bright yellow and the secondary was too dim for me to really make out colour.

6. Don522 8.36/10.62, 2.6": difficult in a small scope but not impossible. I couldn’t make out colours easy (maybe whites or blues) in this hard one.

7. I363 8.18/9.86, 2.3": another close one for you to try, this too was hard to split at the time of viewing. The moon was about 3/4 and the seeing was only ok. I did however make out some colour, white for the primary and maybe blue for the secondary.

8. Dun131 4.76/7.24, 58": you can rest your eyes now with this easy pair. The primary is a stunning white and the secondary a lovely red. Go the Saints!

9. hj4586 7.33/9.09, 2.9": despite the apparent closeness of this double I found it an easy and quite beautiful split with easy discernable colours of white and red. I could even split this at 80 magnification.

10. Cp65 (1744, 1746 and 1747) mags6.47/8.81/8.39: and to end our trip around the fly I have for you a stunning triangular visual triplet. Have fun.

Sharp Splitting!

rmcpb
27-07-2007, 03:05 PM
Dave,

Another cracker, looking forward to the next clear night :)

ving
27-07-2007, 03:21 PM
and i am looking forward to warmer weather :cold:

the only reason i havent been putting more of these out is the cold... I just havent been using my telescope :(
poor dust collector...

rmcpb
27-07-2007, 04:04 PM
Next you will be complaining about the mozzies :poke:

Ric
27-07-2007, 04:17 PM
Thanks Ving, I printed your list and it's ready to go on the next clear chilly night when I'm down in the minus numbers :D

Cheers

ving
31-07-2007, 04:56 PM
thanks ric :)
glad to be of service to the community :)