This article was written for the 50th anniversary of the Apollo 8 mission for Sky & Telescope by HCO director Christopher Taylor. The Sky & Telescope version can be found on their website and Christopher's original unedited version is given here.

Apollo 8 – a view ‘from the other side of the pond’

The evening of 21st December 1968 was fine where my parents and I were then living, the county town of Chelmsford, about 35 miles north-east of London. Even in England there had, of course, been huge excitement about the launch that afternoon of the first manned Moon-mission, our newspapers and television having been full of the story for days previously. It may perhaps not be easy now, in such a very different age, for a later generation to understand the all-encompassing nature of that excitement fifty years ago but there is no question that that general feeling at the time left practically no corner of society untouched and unmoved. This certainly wasn’t just the biassed view of a star-struck 16-year-old, as I was in those days.

The routine of our little household was rarely disturbed, however, by the events and ‘sensations’ of the outside world and that evening my late father and I were out peaceably in the garden some time after nightfall, observing with the 12½-inch Newtonian reflector which I had been given by its previous owner, Mr. R. McIver Paton F.R.A.S., just over a year earlier as the result of a purely chance meeting. That veteran instrument is still in regular use to this day.

Fig. 1: The 12½-inch in 2018

On the evening in question, we were out at the telescope shortly after 6 o’clock (by Greenwich) and had been looking for some time at Saturn, which I was keen to show Dad as it was then well placed in the south. While he was up at the eyepiece some 7 feet off the ground, I steadied the step-ladder on which he was standing and passed the time by gazing about at the rather beautiful sky; a crescent Moon of cat’s-whisker thinness had just set and Venus was playing The Evening Star low in the west. Suddenly my attention was drawn by a first-magnitude star in that direction, which for a few moments I had taken for Vega until it dawned on me that thathad passed behind a large tree on that horizon and that, in any case, this object was noticeably fuzzy despite a cloudless sky of mountain clarity (they do happen in England occasionally!). “Dad, there’s something strange over there in the west which I think we should take a look at” said I.

On swinging the ponderous half-ton mass of the 12½-inch in that direction and remounting the steps, a glance through the telescope’s 11x80 finder (at top in Fig.1, above the main eyepiece assembly) instantly disposed of any notion that this was a mere star. Aligning it on the crosswires, the first view through the main optics was jaw-dropping: a vast nebulous mass, of elegantly parabolic sunward outline sharply defined, nearly filled the 1-degree field of the x75 ‘sweeping power’. Just within its sunward envelope, the cloud was scooped out in two black hollows, symmetrically placed either side of the centre line of the whole, whose adjacent forward edges met in an acute cusp on that centre line, at which point there was a tiny spark of light resembling a star of the 10th magnitude. In short, it looked just like the head of a great comet, an appearance which, inexperienced observer ‘though I was in those days, was already familiar from the picture of Coggia’s Comet 1874 in Sir Robert Ball’s Story of the Heavens, a copy of which had been acquired three years earlier.

 
Fig.2: Coggia’s Comet, plate 12 of Ball’s Story, 1910. 

At that point, just as we were admiring this unexpected celestial spectacle, my mother came rushing out from the house to say that our close family friend Robert Ash was on the telephone, having himself just been ‘phoned by his chum Henry Wildey, who was in a great state of excitement about ‘the new comet’. Henry was a famous figure of British amateur astronomy in the sixties, being Curator of Instruments of the British Astronomical Association (the B.A.A.) and a well-known commercial maker of rather good refractor objectives; I have one of his 5-inch glasses, which is about to take on a new role as guide-scope on the 12½-inch.

Despite all this, I was not convinced that the new object in the western sky was a comet. The sudden appearance – no such object had been in the sky the previous night and it was at a considerable altitude, well clear of the horizon, so certainly no ‘sun-grazer’ – and the perfect coincidence in date with the much-publicized Apollo 8 launch both seemed to lie uncomfortably with that suggestion. Surely this must be something to do with the American Moon-shot? Although, in truth, I had no idea at that moment whether any aspect of the mission could explain what we were seeing, or, even if so, whether it would be visible from the UK. Certainly, no advance notice of any such possibility had come my way.

In fact that is precisely what it was. Apollo 8 had lifted off at 12h.51 U.T. (essentially G.M.T. for ordinary practical purposes) and just under 2½ hours later a burn of the Saturn S IVB booster had flung it out of Earth-orbit onto its long Moon-looping trajectory. Some 2½ hours after that ‘T.L.I.’ and separation of the S IVB from the Apollo mooncraft, that is just before 6 p.m.  British time, the command had been sent to dump all the spare liquid oxygen from the tanks of the now-redundant booster. That large release of volatile O2 into the vacuum of interplanetary space must have blown up very rapidly (near enough at the mean molecular velocity at, say, 300 Kelvin, some hundreds of metres per second) into a huge rarefied gas-cloud, initially co-moving with the Apollo craft and bathed in the Sun’s highly energetic ultraviolet radiation and solar wind: obvious result, an artificial comet-head! The 10th-magnitude ‘star’ at the centre of the cloud was, presumably, sunlight glinting off the hull of the spaceship or the S IVB booster. All of the observed phenomena fit perfectly with this explanation of what was seen that night. 

Although the ‘hairy star’ of 21st December 1968 was not a comet, by far the best representation of what was seen that evening is nonetheless the appearance occasionally displayed by the head of one of the greater of these celestial visitors. It was, however, to be nearly 30 years before I witnessed such a sight again in the 12½-inch, and that despite observing most of the brighter comets of the succeeding decades: Hyakutake 1996 was the best mimic I have yet seen of Apollo 8 on that ever-memorable night.

 
Fig.3: Comet Hyakutake in the 12½-inch, 27th March 1996. 

Certainly, this sketch provides the best impression I can give of the visual appearance of Apollo 8 that night in the same telescope, and that was my immediate thought on putting eye to eyepiece so many years later – the inner and outer parabolae not quite so beautifully defined as in 1968, the central ‘cusp’ a little blunter but in all other respects the moon-shot ‘to the life’.

In hindsight, it is rather curious that such a conspicuous apparition, in an early-evening sky brilliantly clear over a large part of England if not further afield, and certainly observed by a significant number of sky-watchers, was not more widely reported at the time and has left so little trace in what has been written since. I note, for instance, that the long Wikipedia article on Apollo 8, consulted while writing this, makes no mention whatever of any ground-based sightings of the spacecraft or attendant phenomena while in transit. No doubt this is partly explained by its having been broad daylight over the whole of the mainland United States at the time of the S IVB oxygen-dump, so there would have been no chance of anyone there seeing the spectacular sky-display which resulted. It is more surprising that even in the U.K. very little was made of this after the event, even ‘tho a number of experienced observers had certainly seen it. At the ‘December’ meeting of the B.A.A. – actually held on 1st January 1969 – there was a discussion of observations made of the phenomenon by several leading members, briefly reported in the February number of the Association’s Journal(J.B.A.A. 79, 93, 1969). From that report, it appears that photographs were successfully taken by at least three observers, including several from Sevenoaks in Kent by the well-known Commander Henry Hatfield R.N. (1921-2010) but I have never seen any of these published and there is no mention of this in the obituaries of Cmdr. Hatfield.

There was to be at least one further occasion when such a display from the post-T.L.I. propellant dump was witnessed from the British Isles, and that was from Apollo 12 on the night of  14th November 1969. That time, I only caught a brief naked-eye glimpse of the big, fuzzy ball of light, again of about first magnitude, seen momentarily through a rent in flying clouds. Others were more fortunate, however, despite a sky far less favourable than the previous December, and the BAA Journal carried an interesting, fairly detailed report (J.B.A.A.80, 230-232, 1970) of visual observations by 11 BAA members from Kent to Northern Ireland, including one Qantas airline pilot and his crew while in flight.

All this is a very long time ago now but that December night of 1968 provided me with one of the most memorable experiences of my observing life, one which yet lives keenly in the mind’s eye and which conjures up powerful emotions. Not least of those emotions is huge admiration for those brave men who flew in Apollo 8 knowing full well the significant personal risks they were taking, and for the legions of brilliant scientists, engineers and skilled machine-shop workers whose dedication made that great adventure possible: we salute you.

Christopher Taylor

Hanwell Castle,

Oxon, U.K.

Christopher Taylor, a retired mathematics tutor and occasional astronomy lecturer for both the Oxford and Cambridge universities’ departments of continuing education, is best known – if at all! – as a dedicated double-star observer. His observations with the 12½-inch of γ Virginis in the run-up to its dramatic periastron-passage of 2005 appeared in that June’s ‘Sky & Telescope’, pages 74-5. He is director of the Hanwell Community Observatory.

P.S. Click here for a compilation of observations of the Apollo missions from the ground, put together by Bill Keel of the University of Alabama.