On the morning of 15 May, 1957, I was on the upper deck of HMS Messina, with the rest of the ship’s company. We were stopped some twenty-five miles northwest of Malden Island. It was 11am and, since Malden Island is only a couple of hundred miles south of the equator, it was already hot. Certainly, we would have seemed over-dressed, clothed, as we were in long-trousers, socks and boots, and a long-sleeved shirt. This outfit was then topped-off with heavy white gauntlets and (of the same material) a substantial balaclava. The latter two items were what the navy called, ‘anti-flash gear’.
From the loudspeaker system, we heard, “This will be a live run.” We knew what that meant, because we had practiced this performance. The Vulcan bomber, whose vapour-trail we could see high above us, was carrying a thermonuclear (hydrogen) bomb. The bomber was flying from Christmas Island, four hundred miles away, across the equator, the base for a series of weapon tests, of which this was to be the first.
The voice continued, “Vulcan approaching target area ….”. And not long after that, “Weapon released, weapon falling ….”. Then came the count-down, “Ten, nine, eight ..” At “five”, we were instructed to close our eyes, and cover them with our hands (we were already facing away from the target area, the bomber having flown over us). At “zero” there was a white flash, perceptible even through closed and covered eyes. In this situation, some people report having seen the bones of their hands, as if by X-ray. This is probably an exaggeration. A moment’s thought about the relationship in a regular X-ray, between the source of the radiation, the target (the hands), and the detection equipment (X-ray sensitive film) suggests this cannot really be so (the ‘target’ and the ‘detection’ equipment: the eyes) are in the wrong order.
Then there was a count- up to five, when we were invited to open our eyes, stand-up, turn round, and see what was to be seen. We could even take photographs. I have one on the wall in my office. To begin with it looked like a setting sun but above the horizon (the bomb was detonated some ten thousand feet above the surface) and writhing and rising, rather than falling. It was then joined by a column, which came from below, and the whole developed quite rapidly into a characteristic mushroom cloud.
We then went below decks and the ship was ‘sealed” as a pre-set precaution against radioactive fallout. Messina then steamed towards Malden. It was a very disagreeable couple of hours, with no deck awnings on the ship and all ventilation covered. We arrived mid-afternoon, the air was tested and, to our great relief we were allowed out on deck. At this point, we were about three miles from ground zero. A high-air burst, as in this case, produces little ‘fall-out’. Next to no surface material is drawn into the fireball to become contaminated. Radioactive fallout in such a case is limited to the remains of the weapon itself and its casing, and this is taken up to very high altitudes; since the particle size is small, it comes down later and over a very wide area.
In fact, radioactive material from the atmospheric tests of this period is still coming down around the globe, though it should be added, that the radiation exposure that this gives rise to, is only a tiny fraction of the exposure from natural sources to which we are all subject (0.01mSv, as opposed to a global average of 2.4mSv: approximately half of one percent). The dose from nuclear weapon-test fallout is also less than one tenth of the average annual radiation exposure from medical X-rays. It is also worth noting that radiation levels at Christmas Island and the adjacent islands is lower than the global average because of the relatively small contribution from ground sources.
This test was the first in a series of British tests which took place from Christmas Island, over 1957-58. The early detonations were at Malden but later in the year and in the following year, they took place just off Christmas Island itself. For my part, I saw only one further explosion after the 15 May, before my two-year period of National Service came to an end. It had been a memorable time.
But for some that were there, including New Zealand naval personnel, this is not ancient history. It is very much alive because veterans from New Zealand and the United Kingdom (where most of the service personnel came from) continue to press their respective governments in regard to adverse health effects, both to them and to their children. This persists to the present day. The matter is still before the courts in the UK, and it was the subject of a ministerial committee report in New Zealand, in late 2010.
It might also be added, that this controversy is wider than the persisting concerns of veterans of nuclear weapon testing. It overlaps very much with broader present anxieties about nuclear power generally, especially post-Fukushima, and the debate rests largely on the same body of facts about nuclear radiation and the associated risks to human health. Next week’s posting will focus on the claims of veterans of nuclear testing but there is still more to say about the future of nuclear power.