Lunar 100 challenge

The Lunar 100 challenge – are you up to it?

The detailed study of the Moon is called Selenology, and you can do it with a beginner scope.

With nearly no exception, beginner astronomers start by looking at the Moon. After all, it’s the obvious thing, hanging there in the sky looking back at you.

But after watching the Moon for a few nights, lots of people decide it’s time to move on, and begin looking for new sights. What else is up there?

But hang on – why look beyond the Moon in the first place?

The Moon, unlike nearly everything else in the sky (even planets), changes on a daily basis. Several years ago, Sky and Telescope ran an article listing 100 things to see about or on the Moon. The list is here, and starts - somewhat obviously - with L1 “the Moon”, and moves to L2 "Earthshine" (see my photo), before getting more and more detailed. The list was created as a bit of a challenge, and has re-engaged many astronomers with our nearest neighbour.

The Moon is bright, meaning you don’t need lots of light gathering. It’s also big, so for many of the features on the list, you don’t need much magnification. Even a small telescope will show you a lot on the list.

L6 is "Tycho" (named after my favourite astronomer who never owned a telescope). From the Southern Hemisphere, this is THE most obvious crater on the Moon (it's in the same photo). Another one at the easy end is L13 "Gassendi", conspicuous for its crater wall having been blasted a second time.

Of course, towards the bottom of the list, things get more difficult. Try L88 "Peary", the nearest crater to the Lunar North Pole. This one might actually be impossible from the Southern Hemisphere on Earth. Or L90 "Armstrong, Aldrin and Collins", three very small craters in a line near the Apollo 11 landing site. For this one you’ll need extra magnification.

I haven’t done the Lunar 100 challenge, but now that I’ve written this, I’m thinking of it!