It is coming up. Decided to post my brief writeup on a recent observation of this distant but very rich galaxy cluster.
This was done at Lassen Peak parking lot on July 2008.
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Abell 2065 is one of the most distant galaxy clusters visible in large amateur telescopes. This is a very tough group, but fun to work on.
20 galaxies were seen mostly with the 7 and 5mm TMB Supermonocentrics. I used a 7.5mm Tak LE to reorient myself from time to time. I used a 22" reflector at Lassen Peak parking lot. NELM was 7.5 or 7.6 at best.
Three galaxies are obviously brighter than the others.
I’ve labeled the 20 detected galaxies. There are two galaxies that I could not determine the destination of. They are marked as “?”
PGC 54883 and PGC 54881 forms a nice double galaxy separated by a mere 20”. Both are considerably faint and round.
The other bright galaxy, MAC 1522+2747C, is a considerably faint 3:1 elongated even surface brightness patch. PA = 60 and about 15” long. This is located way up on the north edge of the cluster. Actually this was the first galaxy I detected while centering the cluster on my eyepiece.
Starting with the western bright star, the one at mag 10.8.
There are five galaxies in its immediate environs that I spotted. All are very small and very to extremely faint.
PGC 54869
MAC 1522+2742A
PGC 54867
MCG+5-36-17
MAC 1522+2741D
Working my way to the mag 12.9 star to the SW. I spotted only one additional galaxy, MAC 1522+2739B as an extremely faint round glow.
Back to the original bright mag 10.8 star, and working my way to the east, I see a lot of galaxies.
MCG+5-36-20 – is a very faint round patch. 1.4’ east of the star.
PGC 54883 and PGC 54881 is a pair of considerably faint and round. Almost merged and separated by 20”. A nearly equilateral triangle of galaxies due south of the pair of PGC’s are detected as three extremely faint round smudges. They are MCG+5-36-21, PGC 54878, MAC 1522+2741G
MCG+5-36-20 lies between the pair of PGC’s and the 10.8 mag star as a very faint, very small round patch.
MCG+5-36-19 is a very faint round patch lying about 1.5’ north of MCG+5-36-20
MCG+5-36-22 lies very close to a ~16 mag star, as an extremely faint fuzzy star. I almost missed it.
MAC 1522+2739C – extremely faint, very small round patch
MCG+5-36-24 – extremely faint, very small round patch
MCG+5-36-23 – very faint, very small round patch
MAC 1522+2742D – extremely faint, very small round patch
Two questionable fuzzy spots, labelled as "?", were detected, but not labeled as galaxies in Megastar. I’ll need to research it more on the internet. They are located…
1 – just 17” SW of a mag 15 star, which lies 2.2’ WSW of the northern mag 10.5 star.
2 – forms a nice double with a mag 16 star. The pair is located 2.2’ SSE of the mag 10.5 star
Edit: This was from my original write-up. I've done a quick NED check and both are indeed galaxies.
Alvin, I spent 5 hours searching AGC 2065 in 2004 during two exceptional nights at TSP, with my 25" f5 using 661X. I still think this was the most challenging physical observation I have done, as the scope had no drive, and there was often no field star in the eyepiece field, requiring hand driving at high power. I would need to move the scope every 30-40 seconds to reorient the field to recapture the star to make sure of where I was. Using Megastar, which lists about 80 galaxies within the confines of the cluster, and a good photographic reference, I was able to see 51 galaxies total.
While at the Cherry Springs Star Party, a young observer from Pittsburgh asked if he could look at this grouping through my 22" U.C. I saw 2 of the members, MCG+05-36-020 and MCG+05-36-023. His younger eyes saw more than mine. I spent much time picking my way through Abell 1656 and am about half way. This site was NELM of 6.4. My usual site a bit closer to home is 5.8 - 6.0. Location makes a big difference.
Al
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