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akarsh
April 4th, 2016, 04:27 PM
Dear DSF,

Mailyan's catalog of dwarf galaxies seen in POSS images is probably familiar to most of you, but I only came across it ~ 2 days ago when looking into the Steinicke/Jakiel Galaxies book (Springer Verlag).

The book lists Mailyan 16 as a member of the IC 342 / "Maffei" group. I also downloaded POSS images of all 104 Mailyan objects using data from SIMBAD. There seem to be two cases of mis-identification in SIMBAD, where there is a dwarf galaxy in the field, but a brighter non-dwarf galaxy is marked as the object instead (In my opinion, Mailyan 26 should not be NGC 2523, but the dwarf galaxy about 4' south of it; and I believe Mailyan 25 should also be the galaxy ~ 2' north of what SIMBAD returns.). Two of the Holmberg objects are also in Mailyan's list -- Holmberg I is Mailyan 44, and Holmberg IX is Mailyan 48. Many of them seem to have UGC designations.

Just to "try" out this catalog, I picked at random two other objects -- Mailyan 61 and Mailyan 62 -- that seemed to be somewhat tractable or easy to find. Here are observing reports from last night:

Mailyan 16: Threshold observation

Object flashed in a few times in the correct location. The strongest concentration is just shy of forming a right-triangle with two E-W oriented star, being a short distance east of the right-angle point. Could not hold even with averted vision, except maybe for 0.5 ~ 1s on one or two occasions. Extension was felt only on one or two occasions; it was not possible to discern the size and extension of the object most of the time.

Mailyan 62: Negative observation

May have seen a few flashes in the correct location. Not sufficient evidence to count towards a positive observation.

Mailyan 61: Positive

Very very faint, large, roundish glow. Not as faint as Mailyan 16. Could be held 50% ~ 60% of the time steadily with averted vision. Lies in an empty region, so it cannot be confused with anything else, although an asterism seems to catch attention further north (probably a single star; the galaxy next to it seems too faint.) Exact position confirmed by multiple comparisons of the star-field. (The only other prominent galaxy in the POSS II blue plate was also visible with considerable difficulty.)

Clear Skies!

Regards
Akarsh

akarsh
April 4th, 2016, 04:33 PM
Here's a guesstimate of Mailyan objects that may be visible without extreme effort in an 18" telescope under good conditions:

Mailyan 21
Mailyan 36
Mailyan 53
Mailyan 57
Mailyan 64
Mailyan 71
Mailyan 73
Mailyan 75
Mailyan 82
Mailyan 84
Mailyan 91
Mailyan 100

(I have not included the ones reported on above, and the two Holmberg dwarfs.)

Regards
Akarsh

KidOrion
May 3rd, 2016, 05:06 AM
Thanks for bringing this catalogue to light, Akarsh. Hadn't heard of it before.

I suspect these objects are largely (if not completely) beyond the reach of my 12.5" scope, even under ≈ 21.5 SQM skies we seem to get here when it's clear. I'll have to pencil them in for when I'm using the club's 18".

akarsh
May 3rd, 2016, 06:37 AM
I'm sure some of them are possible with a 12.5". For example, I had a positive observation of Holmberg II (also listed in Mailyan's catalog) through a 5" refractor from some very dark skies. The "Galaxies" book by Steinicke/Jakiel lists an observation of Holmberg II by Brian Skiff through a 6" refractor. Granted most of the Mailyan objects seem to be fainter than Holmberg II...

Let me know if you have any luck.

Regards
Akarsh