Roger Griffin’s Midnight Moonlight Meadows Path runs to Grantchester

My father had held for some 25 years an unfulfilled ambition, to run from Cambridge to Grantchester by moonlight. At the age of 71, at last he realised this intention…

First published on 2021 November 26, and last modified on 2022 July 23

Date: Tue, 2 Jan 2007 02:01:17 +0000 (GMT)
From: Roger Griffin
To: Richard Griffin
Subject: Grantchester!

    I just ran to Grantchester!  The sky cleared only at about 10pm, so I did not have an opportunity to recruit company, but I thought I had better do it while there was an opportunity.  The Moon is almost Full, and indeed is higher tonight than it will be again, with the possible exception of one or two nights this year, until about 2024.  I left the telescope looking at something, and it indeed kept itself usefully occupied while I was away, some 45 minutes.  I reduced the time it took by (a) changing right here in the dome instead of going to College, and (b) cycling as far as Barton Road - but I did the principal thing, of running the Meadows Path, and my night was made for me when I heard the clock on Grantchester Church strike midnight just where I turned back, by the Red Lion!

An idea

Those who knew him well would agree that, when in good spirits, Roger’s sense of fun and adventure were rarely suppressed for long. Particularly for an astronomer, the nighttime was not excuse enough to stay indoors in warmth and comfort. Roger had held an ambition for some 25 years, to run from Cambridge to Grantchester by moonlight; he had reached the grand age of 71 before it actually came to pass.

[IMAGE: screenshot of map: 164kB]

On Friday 15 December 2006, Roger and two other members of the Cambridge University Hare & Hounds — a running-club which Roger did not join until after his sixtieth birthday! — met by arrangement at St. John’s College porters’ lodge at 6pm and ran to Grantchester in darkness. There had been discussion on their email-group beforehand (‘Haries’ was a colloquial description of members of the Hare & Hounds), in which Roger demonstrated that the optimum time for a moonlit run would actually be 1) at midnight, 2) at full moon, and 3) in mid-winter:

On Thu, 14 Dec 2006, Roger Griffin wrote:

Hi Haries!
    Of course Mark is correct!  What Haries need is an astronomical expert to set them to rights!  The Moon was Full on the night of December 4; it is coming up towards New now and is merely a crescent in the morning sky before dawn.  You see the Moon in the _evening_ sky, when it might be suitable for illuminating the Meadows path, during the time between New Moon and Full - first as a crescent and then half and then gibbous.  At Full Moon the Moon is directly opposite the Sun and therefore rises when the Sun sets and vice versa.  So it is low down then in the early evening and not so good for illuminating the path as it would be if EITHER (a) one went for a run at midnight (I have always thought what a splendid ploy it would be to run the Meadows Path at midnight under a winter Full Moon* but I have never actually done it!) or else one did the run a few days before the Moon would be Full, because then it would be higher in the sky although not so Full.  But one would not want it to be far from Full, because the brightness of the Moon is not simply proportional to the area of it that is illuminated but changes much more rapidly than that because the lunar surface is not a lambertian scatterer - the Full Moon is about ten times the brightness of the half.
    All the best to you all,

*For the reason that the Full Moon is necessarily opposite the Sun in the sky, it is very high at midnight in the winter, when it occupies the same place that the Sun does at midday in the summer, whereas the summer Full Moon only scrapes along over the southern horizon like the Sun does now. For reasons that I won't bother you with here, the actual excursions of the Moon to the north and south of the celestial equator vary by about plus and minus 5 degrees in a cycle of about 18 years, and we are just at the point in that cycle when the excursions are greatest, so the Full Moons this winter are actually 5 degrees higher in the sky than the Sun ever gets even at the summer solstice.

(Did you pick up that reference to Lambertian scattering? Good! Carry on…)

The idea becomes tempting

Roger was evidently encouraged by the above airing of the science behind the notion of a midnight run, and by the fact that he and two others had run to Grantchester in actual darkness.

A week later, on Thursday 21 December 2006, he was thinking how he might actually pull this off. He emailed me (and in doing so coined the term ‘lunacy’ for this particular type of escapade!) saying,

I quite believe that if I made a concrete suggestion for running to Grantchester at midnight I would get some takers.  If circumstances play into my hands a bit, such as suitable weather at Full Moon and no serious clash with other H&H events, I will see what can be arranged.  There are some of the Hareys who are sufficiently high-spirited that they just wouldn't like to see themselves upstaged by anyone doing such an elementary piece of lunacy [sic] [these puns are getting out of hand] without them!  Of course I would have to shut down temporarily at the telescope . . .

In his role as Emeritus Professor of Observational Astronomy, and in keeping with his habit of the previous 40+ years, when the nighttime sky was free from cloud Roger would be at work gathering data at the 36-inch telescope at the Observatories in Madingley Road — data which formed the basis of a goodly proportion of some 540 astronomical publications which he wrote or co-authored.

First midnight run

As per the highlighted email at the top of this article, Roger duly ran to Grantchester on the night of 1 January 2007, but at such short notice that he was unable to recruit anyone with whom to share the adventure so he ran it alone.

He had a vague intention to centre the run around the middle of the night, i.e. midnight local time, purely to maximise the altitude of the moon and thus the amount of moonlight that would illuminate his way.

Not only did he find that there was indeed sufficient moonlight for running by; but by co-incidence his ‘vague intention’ was so well executed that he was just at the far end of the Meadows Path (by the Red Lion pub where he planned to turn round and return), when he heard the church clock [*] strike midnight. Roger found this most satisfactory and it was immediately apparent that, when he did this again with fellow runners as his guests, he should aim to incorporate this aspect of the experience too!

[*] — This being the Grantchester Church clock made famous in poet Rupert Brooke’s poem The Old Vicarage, Grantchester for its clock being stopped at ten to three.

So it was time to share the run on the next suitable occasion!

The first run with members of the Hare & Hounds

Date: Fri, 2 Feb 2007 14:41:56 +0000 (GMT)
From: Roger Griffin
To: soc-cuhh email list
Subject: Midnight Moonlight Meadows Path

Those who might have been inclined to take up Mark's proposal yesterday but were too late to do so needn't worry - there will be another opportunity tonight (weather permitting, i.e. if there is a clear sky so that the Moon is shining brightly!).  The run will start from St. John's P'lodge at 23.38 exactly (NOT H&H time!), to reach Grantchester at midnight.  It should be explained that such a run, by the light of the Moon, can be done only by the winter Full Moon (Full Moon is today): it will be appreciated that the Full Moon is necessarily opposite the Sun, and so is highest (a) in the winter and (b) at midnight.  It is too low in the summer to give good light.
    I would appreciate it if anyone who wants to join in the run would send me a message to that effect.  If I have had no takers by 10pm, or it is overcast at that time, I shall send out another message cancelling the event.  I will [be] accessible on the phone at (3)3**** most of the evening, and in particular between 10 and 11.  Look forward to seeing you!
    All the best,

As is hinted, Roger and fellow ‘Harey’ Mark had gone on the run together on 1 February 2007, and now (as above) Roger had advertised it with sufficient forewarning that there was a good prospect of several ‘takers’. This all worked out quite well. Roger emailed me the following evening with an account of how it went:

Date: Sat, 3 Feb 2007 22:45:41 +0000 (GMT)
From: Roger Griffin
To: Richard Griffin

    I organised a midnight run to Grantchester along the Meadows Path by the light of the Full Moon last night!  I had to intermit my observing because I had to do it properly - go to College to change and meet the others, and I defined an exact time of 23.38 to start, with a view to arriving just in time to hear the clock strike midnight.  I had not had my supper, so afterwards I went home for a quick supper and then returned to finish the night, getting home at 31.15.  There were five other H&H people who turned up for it; a lot more would probably have come except that they are away as it is the BUSA competition this weekend.  And I received apologies for absence, from people who said they wished they could join in but were too far away, from Wimbledon, Geneva and Vancouver!  I got a little bit of private amusement out of the thought that it was a ploy that had not been thought up by the headstrong young but was organised for them by a poor old man in his dotage!  I am wondering whether it will come to be considered a routine thing to do on the occasion of winter Full Moons, because the fact that there are people away at the moment probably means that there is an unsatisfied demand!

Roger commented that “I expect we made an unusual sight running along KP [King’s Parade] at such an hour of the night.”

What Roger didn’t mention to me, but which I since discovered, is that a couple of the takers on this inaugural Midnight Moonlight Meadows Path run had not understood the purpose of — and got bored of — Roger’s intentionally careful running-pace and took over the lead with a fearsome pace “with which I could hardly keep up, with the counter-productive result that we arrived at Grantchester three minutes too soon, which if they had left it to me we would not have done, so we ran the little loop past the Red Lion and *then* the clock struck! And then they made a race of it back and it was altogether beyond me to keep up, so I was left to run back by myself, which was not really what I had anticipated. They did apologise afterwards.”

Subsequent ‘lunacy’ runs

Roger told me that he had had takers every time since, and he is pleased to discover that he can do something that young people would actually find amusing and unusual enough that they hadn’t thought of it themselves!

On 3 November 2009, Roger circulated a message to the same email list, “in continuation of an event that has occurred the last three winters”, and noted that the run would start at 23.39 exactly (he had felt that the pace required for a 22-minute run was slightly on the slow side). He had 2 takers on this occasion, and timed it so well that they had just 20 seconds to wait before the clock started striking!

The last recorded instance of Roger undertaking a ‘lunacy’ run was on Friday 9 December 2011: he had one taker in response to his announcement via email, and he managed to pre-arrange the 36-inch telescope’s dome and autoguider such that neither caused his observation to falter nor to self-abort during the 2 hours that he was away on the run, showering afterwards, et cetera.

Seeing in the New Year

Date: Thu, 31 Dec 2009 20:47:58 +0000 (GMT)
From: Roger Griffin
To: soc-cuhh-hols
Subject: Midnight Moonlight Meadows run

Is there anyone around who is not already committed to some other occupation tonight and would be amused to do the midnight run to Grantchester?  It is an amazing opportunity actually, because the Full Moon will only coincide with the night of the New Year on average once in thirty years, and it is doing so tonight - and it looks as if it will be fine!  Please let me know if you are interested in joining me - leaving the Great Gate of St. John's at 23:38 exactly (NOT H&H time!).
    Happy New Year,

As he describes in his announcement above, Roger was keen to capitalise on the coincidence between New Year 2010 and Full Moon. In the event, perhaps unsurprisingly nobody was free at such short notice on New Year’s Eve to join him on this run. On his way back, he called in at his church (St. Edward’s) where some sort of New Year’s celebration was taking place; he was dressed in fluorescent yellow top and bottoms and he related with some amusement how the vicar was NOT amused — but a couple of the other people present were!

Article in the Guardian

Roger had offered his advice to the organisers Ceri and Ben of a nighttime running-race which was to be marketed as a ‘moonlight flit’, which resulted in an article in The Guardian.

Letter in the local newspaper

[PHOTO: Newspaper cutting: 75kB]

Above: Roger wrote a letter which was published thus on page 6 of the Cambridge News and Crier on Thursday 15 July 2010; it evidently is in response to a planned ‘moonlight walk’ which was going to suffer from the same summertime difficulties as the above ‘moonlight flit’.