A few nights ago I managed my first lunar sketch in a couple
of months. Come to think of it, the last twelve months have been pretty lean of
sketches from me - work, poor conditions, cloud, all conspiring against me.
This particular night all my ducks finally all lined up - excellent seeing,
work not in the way, and an itchy sketch pad
The brilliant crater Aristarchus and the sinuous Vallis
Schroteri all too often steal the show in this area of the Moon, an area that
appears to harbour very little other detail or features. How wrong this
thinking is! It is only a very shallow angle of sunlight that can reveal the
wealth of detail that actually litters this area.
At sunrise over Aristarchus reveals a series a very fine,
long lava rivers, and for several of these the head of each river can be traced
to different volcanic domes. These lava rivers are not as pronounced as Vallis
Schroteri, so when the Sun is higher up their shadows are lost. These volcanic
features are visible for only a few short hours each month.
There are also a multitude of volcanic domes all around here
too. Most of these would go unrecognised as such because they look like a
mountain. But one tell-tail sign of their true nature comes from careful
examination of the shape of these peaks - domes tend to be more rounded in
shape, like a blister. When the angle of the incoming sunlight is as shallow as
this, it can be difficult to make out this blister shape. But leave the timing
too long after sunrise, and these domes disappear because they are not very
tall, and their rounded shape does not allow for stark and sharp angles that
true mountains have.
The shallow angle of sunlight also makes for very dramatic
long dark shadows that extend out towards the terminator and beyond it. It
never ceased to amaze me how quickly these long shadows actually recede as the
Object: lava rivers and domes between Prinz &
Scope: 9" Santel Maksutov, MK91
Gear: 7mm Vixen SSW eyepiece, 443X
Date: 1st August, 2020
Location: Sydney, Australia.
Media: White & grey soft pastel, charcoal and white gel
ink on A4 size black paper.