Wednesday, June 20, 2018

aimed to M24 (Halifax)

I asked the Burke-Gaffney Observatory to image Messier 24. This open cluster or "star cloud" aka IC 4715 in Sagittarius I only have a single log note for so I wanted to revisit. First viewed this target on 5 Jul '08.

region near Messier 24

Luminance only, 5 seconds subexposures, 20 stacked shots. FITS Liberator, GIMP. North is up; east is left.

It look me a while to identify the field. Compared to the location marked in SkyTools 3 Professional, this field of view is west and south. The amazing wikipedia says that some improperly identify M24 as the faint cluster NGC 6603. This is what happened in ST3P.

Ending up in this slightly different location however was fortuitous. This field includes other catalogues clusters and some double star systems.

West from centre, near the edge of the field, is a tight, nearly equal pair of stars orientation north-west to south-east. This is the double ARA 468.

South-west of centre, a short distance away, is a small grouping of bright stars. This is the Turner 4 open cluster. It appears to have some double stars within it!

South, near the edge of the frame, is a large grouping of stars, some of which are arranged in a scraggly vertical line. This is open cluster Turner 2. The wide pair ARA 470 is at the southern limit of this line.

Open cluster Turner 3, with what looks like a little Cassiopeia W-shape of stars, east of 2, is partly cut off.

South-east, well away, is the multi-star system HD 167863 aka SHJ 263. The primary is the bright star to the south. B is bright too, not as much, to the north-north-east. Between A and B are the pair of stars S and T, west to east. They are equal. Inline with S and T but further east is the U element. U is dimmer. West of S and T, in a similar alignment, is the fainter pair of V and W. V is to the north-west and dimmer than W. The R companion is near B, to the south-east. A neat little system. Note: it is a target in the AL advanced binocular programme.

ARA 473 is a simple pair to the north-east. Wide. Actually, the A star is slightly dimmer than B. The SkyTools chart shows B is mag 10.9 vs 11.7.

A busy part of the Milky Way...

Upon review, I think I"ll leave M24 in the View Again list. It should really be viewed with binoculars or at very low telescopic power.


Wikipedia link: Sagittarius Star Cloud.

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