Telescope Reviews: Sky Atlas-project sketches 2009

Telescope: 4.1" Tal-1
Obs. place: Tottijärvi, Nokia, Finland
Date: 10./11.4.2009
Bortle class: Class 3
NE Lim.mag: - (not measured but close to 7)
Background sky: 2
Seeing: 1-2
Transparency: 2
Weather: +0°C, no wind, 98.1% moon rising from the east.

I started with something simple and easy that I could locate without maps - Messier 37 in good old Auriga. I am not at all pleased with any of the previous sketches I have of it so here was my chance. The sky was still quite bright and twilight was obvious but I didn't have much time to waste. The shape came out pretty peculiar but I was still pleased enough to scan and upload it. The best view came with 107x. I counted roughly 90* of different colors (mostly light blue and few reds and oranges) within a 10' radius."

Messier 37 with 4.5" Tal-1 @ 107x

After sketching M37 I moved the telescope gently down to Cancer and M67. The cluster is one of my favorites. Maybe it has something to do with the first time I viewed the cluster and clearly saw an octopus or maybe not but there just is something about this ancient cluster I just find hypnotizing. It is quite not as rich looking as M37 with small apertures but still is quite the eye catcher. To keep the cluster as compact as possible I decided to go with the 64x for the field of view."

Messier 67 with 4.5" Tal-1 @ 64x

Viewing NGC 3172 has nothing to do with the Sky Atlas-project but I've always wondered if it could be spotted in an instrument smaller than 6". In the 1996 book "Syvä Taivas" ("Deep Sky" in English) the author and legendary deep sky observer Risto Heikkilä states that "The galaxy can be seen even with small instruments. Stephen Knight from Maine, US has reported seeing the galaxy even in a 6" telescope". So could I do it? The moon was rising from the east and it was going to be big and ugly. Wolfgang Steinicke's NGC-data has the galaxy listed at 14.4 (v) magnitude with a surface brightness of 13.9. This does seem a tad bit too faint. Uranometria field guide has it at 13.8 (v) magnitude and surface brightness at 13.5. This seems to be closer to the truth.

I popped quickly back in the house to get my laptop and a printed map of Uranometria's page 1 (which proved totally useless). I thought that even if the galaxy itself was invisible I could do some limiting magnitude tests with the telescope. Luckily that wasn't necessary. Using the telescope @ 162x I was able to spot a faint but still an obvious round, even brightness glow in the correct position - SE from the star GSC 4644-0086. I sketched all the stars in the field and the faintest one visible was roughly 14.8 (v) magnitude.

I have to say I was quite pleased. All this was done with a low quality 3x barlow lens and even worse quality 15mm Kellner eye piece. I'm sure I could have gone a lot deeper with my own Baader Hyperion oculars.

NGC 3172 with 4.5" Tal-1 @ 162x

I had time for one more object before the girlfriend would be out and demanding to see something more... "rewarding" with her telescope. I wanted to try for a planetary I haven't seen in a few years - IC 3568. I maxed out the magnification and long story short, here is the result: "Bright disk with a fairly bright central star".

IC 3568 with 4.5" Tal-1 @ 382x

/Jake