The Last Moon

Every year for several years I’ve had an invitation spend the morning with two classes of Year 5 pupils at the Churchill School during their ‘Space’ curriculum topic. Not once has this been less than a delight; it’s always great fun (see here and here to get a flavour). This year’s trip took place in late June – timed such that their preferred target of the Moon was up in the daytime and was no more than about half in sun. The reason for not wanting either a crescent Moon or a full Moon is that we want a chance of seeing a selection of craters, lava basins and mountain ranges but we also want some decent shadows arising from a low Sun in the lunar sky. On that latter point, the ‘best’ shadows are those near the terminator – the line that divides night from day. There are several options for such planning, but the website I tend to use is here.

This is my small, i.e. reasonably transportable, telescope and mount: a Skywatcher 72ED on a Skywatcher EQ3/2 mount (- the image above wasn’t taken during this visit). I’ve retro-fitted motors to the mount in order to track the motion of objects across the sky as the Earth rotates; indeed, this is an enormous help when attempting a ‘mass observing event’ since the target – the Moon – isn’t continually drifting out of the eyepiece’s field of view.

Having learnt the hard way that the variation in height amongst ~60 ten year olds can make viewing tricky I’d purchased a right-angle for the eyepiece which could easily be rotated to suit all-comers. That worked well. Inserting an additional lens (a 2X Barlow for those who wish to know) which, in effect, doubles the magnification was less successful since it has the effect of ‘dulling’ the image. At night this isn’t a problem when viewing the Moon, but on a bright and relatively humid morning in mid-summer when the contrast is already reduced it had the effect of ‘washing out’ the details on the lunar surface. However, once committed to the setup there was no time available to reconfigure everything once observing began. One lives and learns.

This wasn’t taken on the day – it’s an image I prepared earlier ;-) However, it does show the sort of view I had hoped to show everyone – albeit somewhat degraded by the daytime conditions. For anyone wishing to identify features on the Moon when observing by eye, using binoculars or a telescope I’d recommend a phone app called ‘Lunar Map HD’ – although there’s a lot of other online resource also available.

Unfortunately, this is the sort of view we all got: the moon on a bright, humid day in the middle of summer - washed out.

Everyone saw the Moon through my telescope as far as I know, although it took some people less time than it did others to get their eye in just the right position to see it. (One person did come back for a second attempt right at the end, having failed to see much when it was their turn. I’m glad that they did; it would have been such a shame to have said nothing and as a result missed the experience.) After we’d finished there was an hour of Q&A back in the classroom. It’s rewarding to be able to show people a view of the Moon that they might not have had before, but it’s definitely huge fun to attempt to field an apparently never-ending stream of testing questions. Every year I’ve been invited to visit this school I’ve been blown away by the energy and insight behind the questions. Yes, there are some that might be written off as left-field or off-piste – but that would be to miss a key point: these are all young people who’re engaged with the wider subject matter, and many were genuinely well-informed. Enthusiasm is worth a lot.

Nothing trumps break time, and nor should it – particularly at that age – and the time rapidly arrived for me to take my rig apart again and return it to the boot of my car. I was helped by my two wonderful Year 5 host teachers, in the course of which they told me about their new teaching assignments for next year. Apparently neither of them will be teaching Year 5 – so my astronomy/space mornings have in all probability come to an end. That visit may well prove to be the last observing session I assist with at the school; no more shared Moon ...