posted: 1254 days ago, on Monday, 2016 Mar 14 at 03:48
tags: astronomy, deep sky, observing report, SQM, astrophotography, Leeuwenboschfontein.

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Leeuwenboschfontein is a lovely guest farm in the Klein Karoo, north of the Waboomsberge in the Nouga Hills (midway between Touws River & Robertson). It is an easy drive; head on to the N1 from Cape Town; 21km before Touws River, take the R 318 and drive south for 27 km to a gravel road turnoff. About 11km later you're there; your GPS should then read 33° 34′ 00 S, 19° 59′ 08 E.

Our group consisted of Ed & Lynnette Foster, Alan & Rose Cassells, Louis Fourie, Iain Finlay, Willem van Zyl, Barry & Miems Dumas. The guests of honour were ⁠⁠⁠⁠⁠Klaas van Ditzhuyzen and his charming companion Wilna. Klaas is an accomplished astrophotographer, a well-travelled astronomer, and a knowledgeable chemist (amongst other things!) from the Netherlands.

Visit Klaas' website, northsouthsky.com, for a glimpse into his fascinating life, which includes a report about this weekend.

Our first evening, Friday March 04, was an observing joy. SQML-L readings ranged over 21.54+/-0.00 and 21.68+/-0.03, and the seeing was very good. I spent a few hours binocular observing, and taking unguided wide-angle astrophotos.

Two memorable clusters, always well worth a closer look, are NGC 6208 and IC 4651. The duo are located in Ara, a lovely area to sweep with the relatively high-powered Celestron 17x50 binoculars. The black background is punctuated by a wealth of white star sparkles, some with a hint of colour (like zeta and epsilon-1 Arae). "Behind" the stars the ground of the Milky Way is uneven, with tracts of irregular black regions intermingled with barely perceptable glowing patches. Nudging the binoculars "up" (or just 1.5° west) from epsilon-1 Arae reveals a well-isolated feature within the very rich star field. This is NGC 6208, a large nebulous puff of light, at first round in shape but upon study very slightly elongated NE-SW. With some concentration it may be mottled, but not certainly so. Nearby epsilon-1 and epsilon-2 Arae are handy for estimating its size: about 13-arcmin. [1/3 to 1/2 of the separation between the two stars.] NGC 6208 is easy to locate; it lies at the western corner of an isoceles triangle with zeta and epsilon-1 Arae, 2.6° distant from zeta. John Herschel's description is spot-on: "A pretty insulated milky way cluster...".

Nearby IC 4651 is a gorgeous open cluster, beautifully positioned in a bright Milky Way field. It is difficult to avoid comparing it to NGC 6208: for one, IC 4651 is brighter than NGC 6208, breaking the "rule" that IC objects are fainter than NGCs. Secondly, the two clusters share a congruent placing: IC 4651 lies at one tip of an isosceles triangle with two bright stars, alpha and kappa Arae (1° west of alpha). Binoculars show it easily, appearing as a large, approximately round nebula, about 10' across, which is prominently mottled. A curious visual feature is the impression of an off-centre halo. The obvious part of the cluster is the brighter, roughly round figure, which seems to have a faint crescent rim to the south-west (as if an offset fainter cluster lies behind it).

Louis and myself spent some time together, drinking coffee, staring agog at Saturn, and enjoying high-power views of the blue/green/gray/tan-coloured NGC 3242, the Ghost of Jupiter. After moonrise, Louis posed for a photo with his C14, and we ended our session just after 04:00.

Louis Fourie at the eyepiece of his C14, with the Moon rising below the Milky Way.

2016.03.05, 02:46 SAST. EOS 60D, 10-mm f/3.5, ISO 3200, 17x 44-s frames. No darks.

Socializing

After the perfect condition of the first night, clouds and drizzle prevailed, giving us an excellent opportunity to relax around a braai fire.

Iain, Willem, Alan, Rose, Lynnette, Ed, Louis, Klaas, Barry.

nothing more to see. please move along.