September target M31

[The Warthog]

The skies were so bad tonight that I had difficulty defining the square of Pegasus, which I use to start star hopping to M31. When I finally sorted out where M31 was supposed to be, I put myself in the general area with the red-dot finder and looked around with the 7x50 finder. I realized that I had been identifying Alpha Andromedae correctly when I stood back and looked at the sky, but when I bent over the telescope and looked through the red-dot finder I was lining up on the next star down. When I figured that out, I put the red dot on approximately the right place, and looked through the 7x50 finder. Finally located a dim smudge, and moved it to the centre of the crosshairs. In the scope at 32x it was hardly there, but it was defininitely M31. When I saw it in dark skies in August, it was bright, and I could clearly see M110 beside it. Tonight all I could manage was the core of the galaxy. It was pretty unimpressive. At 150x there appeared to be some structure in the core, but it was still not very big, certainly all I could see was an oval covering about 10 arcseconds. Skies were mag 3 at best in that part of the sky although the seeing appeared to be pretty steady. It was well past astronomical twilight, at least. I have certainly had better luck with M31, even from my back yard.

[Astroman]

Clear, darks steady skies Friday night, September 22, 2006 9:30pm local time. Temperature ~30ºC, wind ~10 kph gusting slightly. (This is where the dome helps, especially when the target is east and the wind is from the west )

Scope:10" F/5.6 on ancient Cave mount.

I observed M31 with ease with the unaided eye before lining up the scope. Loomed very large in the finder scope. The 32mm Plossl gives 44.5X. Roughly 1/3 of the galaxy is visible at this power, so I sweep back and forth along the major axis to observe M31. It is a very large, very bright galaxy, seen in nearly isometric relief. Elongated NE to SW. Very bright mottled, resolvable core, with distinct structure away from the core. Two satellite galaxies, M32 and M110 are easy at 1:00 and 7:00 positions, respectively in the Newtonian inverted FOV. Details and dust lanes in M31 are subtle, but visible with averted vision and deep dark adaptation. (I spent 1/2 hour in the dome with all the lights out, staring at the floor before climbing the ladder.) Spiral arms are also visible in M110 as mottling, as is the core of M31. Cranking up the power to 189X with the 7.5mm reveals G1 and G2-globular clusters in M31 located about 1/2 galaxy diameter to the southwest of the core. This was my first attempt at G1 and G2. G1 was visible as an extended star, but I failed to see G2. Too dim perhaps, but it should be within reach.

M31 is a magnificent galaxy when seen and studied from a dark site. Time must be taken to observe it properly. If your skies are not too dark, or if nearby lights intrude, a dark cloth hood over your head to block it can't be recommended highly enough. Give yourself time to dark adapt, you'll be rewarded for the extra effort. It may seem silly to do all this to see such a close, bright object, but, as I always say, the more you look, the more you'll see.

Cheers.