Schickard and Wargentin
On the evening of 22 April 2005 I shot an image of a few interesting features on the south-western limb of the Moon. There where however two that caught my immediate attention, Schickard and Wargentin.
Where to find Schickard and Wargentin
Schickard is a large old crater with a diameter of 227kilometres. When observing Schickard through a telescope, you will immediately notice the absence of central peaks or peak rings. You will also see
that there are some large patches of dark and light material on the crater floor.
Schickard is very shallow compared to other craters of this size, only about 1.5 kilometres deep (Clavius is 5 kilometres deep). The original crater floor probably has been flooded with lava which covered the central peaks completely. After that a thin layer of bright highland material was thrown like a blanket over the dark crater floor (ejecta from the Orientale Basin formation). This bright layer is still visible in the centre of Schickard. Near the edges of the crater (upper left and lower right) there was some additional lava flooding later on. These are the dark patches that can be seen in Schickard. (See C. Wood, the Modern Moon pages 177/178).
Wargentin is a very mysterious crater. It seems as if this 84 kilometre wide crater is filled right up to the rim, looking like a kind of plateau. Wargentin indeed is completely filled, probably with volcanic material, and covered with a layer of brighter highland material (again from the Orientale Basin formation). You can see the rim of Wargentin very clearly as well as one or two wrinkled ridges on its flooded floor.
Other interesting features to explore in this region are the elongated crater Schiller, which together with Zuchius marks the Schiller Zuchius impact basin and of course Bailly, another impact basin south of Zuchius.
Click to enlarge
The image is the result of stacking 10 images shot with the 8-inch TAL 200K, a 32mm Televue Plossl and the Nikon Coolpix 4500. Settings of the Nikon Coolpix: s-mode, 1/30s, f 5.1, iso 100, 4x optical zoom, 2272x1704 pixels. The image was processed using unsharp masking and level adjustments.
Posted by Math
on 07/01 at 05:30 AM