It's hard down South

The Craters: Tycho, Maginus and Clavius
at the Moon's southern limb
(Image taken from our Backyard : Meade 127mm Apo refractor and QHY5v planetary camera)

The Moon's southern highlands are pitted with large craters which stand out well when illuminated obliquely by the Sun. Clavius is the third largest crater on the nearside of the Moon, it is roughly circular, although it is visually foreshortened  in the north-south dimension because of its location near the South Pole, it has a diameter of 231 kilometres.

To give this a sense of scale, if you superimpose the outline of Clavius on the United Kingdom it would cover an area of land from our home in Lowestoft in the east to Oxford in the west and Lincoln in the north and Winchester in the south.

NASA's image of Clavius
superimposed on a map of the United Kingdom

To the left of Clavius is the crater Tycho. Smaller and younger than Clavius, having a diameter of 86 km.  At full moon Tycho is clearly visible with the naked eye. When the Moon is full and illuminated by the Sun at 90 degrees, the ray system created by ejecta from the impact is clearly visible. The central peak in the crater was an immediate after effect of the shock to the moon's crust created when the incoming asteroid or comet impacted. The central peak can be seen in my image as the bright dot in the middle of the crater.  In reality this peak rises over 1.5 km above the crater floor, some 200 metres higher than the summit of Ben Nevis the highest peak in the United Kingdom.

Ben Nevis credit: www.walkhighlands.co.uk

Don't you just love the Moon?

"next time you walk outside on a clear night and see the moon smiling down at you, think of Neil Armstrong and give him a wink."

Credits: NASA and Walkhighlands