The Sun Solar System: the Moon Planets observing logs

April 1st, 2004: Lunar observing log: Overview of an 11-day-old moon

The images below was taken on April 1st 2004. The Moon was 11 days old. The instrument used was an f 10 8-inch TAL Klevtzov-Cassegrain on an equatorial mount. I shot the image with a Nikon Coolpix 4500 mounted to the telescope with a Vixen digital camera adaptor. The eyepiece used was a 25mm Vixen Lanthanum (48x). The images below are the result of stacked images (2272x1704) stacked with Keith's Image Stacker (Mac). The stacked images were resized and the orientation was changed (the same is in the Rukl) using image-processing software. I also applied some unsharp masking. I did not use any filters.

1. Overview image of an 11-day-old Moon

In the north, on the edge of Mare Imbrium lies Sinus Iridum (Rukl 10), the Bay of Rainbows. To the south-southwest you can see two craters with clear extensive lunar rays, Copernicus (Rukl 31) and Kepler (Rukl 30). On the southern half near the terminator lies Mare Humorum with the big crater Gassendi (Rukl 52) on its northern rim. A bit further south along the terminator lies the very elongated crater Schiller (Rukl 71). To the east of Schiller you can see the crater Tycho (Rukl 64) with some of its lunar rays clearly visible. One of the rays runs to the rim of mare Nectaris, with a total length of 1300 kilometres. Let's have a look at some areas more detailed.

Image 1 : overview of an 11-day-old moon

2. Sinus Iridum (the Bay of Rainbows, Rukl 10)

At the of this image we see Sinus Iridum, a 260 km wide crater. The visible part of the rim runs from southwest to northeast and is called the Montes Jura or the Jura Mountains. They reach a height of 5000 meters. The rim ends with two capes projecting into Mare Imbrium (the sea of showers). The northern cape is called Cape Laplace; the southern one is called Cape Heraclides. The southeastern part of the rim is missing, but is probably buried under Mare lava from Mare Imbrium. In the Jura Mountains you can see a large crater, Bianchini. To the south of Cape Heraclides lie two dome-shaped mountains, Gruithuisen Gamma and Gruithuisen Delta (Rukl 9). North of Sinus Iridum, between the terminator and Mare Frigoris, you can see a large old crater, Herschel (Rukl 2)

Image 2: Sinus Iridum

3. Mare Humorum (Rukl 51/52)

The largest lunar features visible are the impact basins. Mare Humorum is the centre of one of them, the Humorum basin. You can see Mare Humorum with the naked eye. It is about 380 kilometers wide and surrounded by a few craters that will help you with your orientation. On the northern rim of Mare Humorum lies Gassendi, a 110-kilometer wide crater with numerous rilles, hills and a group of central peaks on its floor. In the north, the 33 kilometers wide crater Gassendi A has broken the rim of Gassendi. To the west of Mare Humorum you can see a larger crater rim lit by the sun. That's the 84 kilometer wide Mersenius. In the south lies another big shallow crater with a central peak, Doppelmayer. The rim of Doppelmayer is breached on the mare side.

Image 3: Mare Humorum

4. Schiller and Tycho (Rukl 64 and 71)

In the lower half of this first image you can see the large, elongated crater Schiller. It is about 180 kilometers long and 70 kilometers wide. The floor of this crater looks very smooth. To the west-southwest of Schiller you can see the outline of a larger circular structure. This is the Schiller-Zuchius basin.

Image 4: Schiller

At the centre of this last image you can see the young, complex crater Tycho. On this image you can see the lunar rays spreading in northern and eastern direction. These rest are best viewed when the Moon is full.

Copyright © 2004