Moonbow
Apropos Tony Newman’s “lunar rainbow” (Letters, 18 March): I have also witnessed this phenomenon, although at moonrise. It happened two years ago in the Philippines. I and a companion were fishing by torchlight off the coast. We had just emerged from a tropical downpour which was still throwing down thick curtains of rain from a heavy overcast sky a few hundred yards further out to sea. At this moment the Moon, rising very low over the land, produced a flawless rainbow against the storm.
Unlike Newman’s, there was nothing brief about it. It was a perfect grey arch which looked like frozen smoke against the black background, both its ends planted in the sea. It lasted eight minutes by my watch before fading, longer than any daytime rainbow I’ve ever witnessed. What is more, a secondary bow was just discernible above it, as well as exceedingly faint bands within it.
These presumably were the lunar spectra. Possibly, moonlight escapes from water droplets at an angle slightly different from that of the 42 degree solar rainbow ray? I have never yet seen a reference to such rainbows, not even in travel accounts, though doubtless they are well documented somewhere.
My companion was terrified, convinced it was a portent. I assume his fear testifies to the phenomenon’s rarity. Yet that, too, is strange. I can’t see why the right conditions of strong incident light on falling rain should occur any less often by night than by day. Maybe it is the observers themselves who are rarer. In any case, I certainly agree with Newman that the effect is sublime 鈥� mysterious and exhilarating.
Offending Wotan
What would you do if one of your correspondents claimed, in passing, that Christians believe their God had been chewing tobacco and, needing to expectorate, created the world as a sort of primal spittoon?
I imagine you would reject the letter. To start with, the claim is untrue. Secondly, the ability to be so wildly wrong in such a veritable matter is hardly a recommendation for the rest of the writer’s letter. Thirdly, it would be offensive.
And yet you were willing to publish Ralph Estling’s claim that “the ancient Germans” believed that “Wotan had drunk a large amount of beer and urgently needed some place on which to relieve himself, so he created the world as a sort of primal chamber pot” (Letters, 18 March).
No ancient Germanic people believed anything of the sort. In fact, from all variants of the Germanic creation myths that have survived, it is clear that several worlds were seen as having come into being before any of the gods. In the most comprehensive surviving account, the Icelandic poem known as “The Song of the Sybil”, the gods only had a role in creating one of the nine perceived worlds, the realm of men and women. In my translation our world is described as having been “moulded in magnificence” 鈥� reverential language that is completely at odds with Estling’s strange and scatological claim.
So what is going on here? Are the religious views of our own ancestors considered uniquely appropriate for undignified jokes. Or don’t you know that the indigenous beliefs of the Germanic peoples have been revived this century, and that versions of them are legally recognised as living religions by several Western governments?
Perhaps I am one of the few adherents of such a religion who reads every word in New 杏吧原创, but on behalf of those who don’t I would like to lodge a friendly protest. Estling’s statement was not just completely false, but also offensive.
Close call
Adrian Bowyer speculates that quasars could be fusion powered spacecraft moving away from us (Letters, 1 April). If this were so, they would be concentrated (from our viewpoint) in clusters around the centres of the civilisation(s) which launched them. Even a widely dispersed civilisation would surely tend to settle near what it considered to be suitable stars and, of course, stars are not evenly dispersed in our sky.
I can conceive of only one scenario that could reconcile the spacecraft explanation with an even observed distribution of quasars and that is those that we observe were launched close to us compared with the distances the quasars are from us. In this case where are they and why have they not come here yet?
Spot on
I have been following the correspondence on teenage acne with some interest and have just read David Feldman’s letter published on 11 March.
He suggests that acne is a signal that humans are not yet mature enough to reproduce. This is a nice theory, but from experience I can see some problems with it. Firstly, acne is known to continue well past the teenage years in many cases. I myself am 20 years old and still suffer. And I have plenty of friends in their early twenties with the same problem. A person in their twenties can surely be considered mature enough to reproduce. And what about 30 year-olds who still suffer acne?
Secondly, I also know people who have suffered approximately five spots in their entire teenage years (in fact, several individuals with this type of complexion seem to grace the covers of many magazines). So where do they fit in?
My personal theory is that acne is an independent life form 鈥� a parasite that feeds off certain negative emotions, for example stress caused by low self-confidence. Humans are considered the only species to show such a wide range of emotions, are they not? And everybody knows acne always breaks out 24 hours before parties and school photo sessions 鈥�
Correction
Jay Pasachov of the Hopkins Observatory, part of Williams College, points out that the college is in Williamstown, Massachusetts, not Maryland (Letters, 1 April).
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Antiproton show
The nice article by Paul French, “The light fantastic medical show” (11 March) includes a box “The inside story”, which in effect suggests requirements for best finding out about the body’s internal workings; MRI is suggested as the most powerful existing technique.
It is perhaps not as widely known that an exceedingly promising technique for such surveys lies in biomedical applications of antiprotons, a possibility first suggested by T. E. Kalogeropoulos of Syracuse University, and summarised by me in a brief article for the 1995 McGraw-Hill Yearbook of Science and Technology.
Use of antiprotons satisfies every requirement noted in the cited box, and then some: very high resolution in imaging with low radiation doses, the ability to map every element in the body, the potential to combine precision imaging with concurrent radiation therapy, and other properties.
The combination of possibilities for antiproton use for imaging, diagnostics and therapy is not approached by other techniques. It is to be hoped that medical practitioners become familiar enough with these possibilities to develop the critical mass of interest leading ultimately to routine medical applications of antiprotons.
Very, very long
The February issue of Scientific American carried an article by Moshe Elitzur in which he mentions the linking together of 10 US radio telescopes to form a Very Long Baseline Array stretching from Hawaii to the Virgin Islands and providing unprecedented resolving power. He also mentions a Japanese-Russian plan to launch a telescope orbiting in space.
I am surprised nobody has suggested the construction of a Solar Orbit Radio Telescope (SORT) by distributing radio dishes all around Earth’s orbit. The space shuttle could be used for carrying the dishes into space. The technology for coordinating the dishes exists and the whole project would cost less than some of NASA’s other schemes
Turning the Earth’s orbit around the Sun into one gigantic radio telescope will provide data never imagined before.
Ice is nice
The article about Antarctic stations did nothing to raise my opinion of architects (“Paradise lost?”, 18 March). As usual, there is a preoccupation with originality and visually impressive structures with little regard to cost 拢200 million I’d do it for a tenth of that and retire rich.
To anyone with experience of cold climates, the site is provided with plentiful, cheap building material, namely ice. In the south polar climate, ice is eminently suitable as a permanent building material.
I don’t suggest cutting and stacking ice blocks Eskimo fashion 鈥� that’s a little too labour-intensive. If I had the job of constructing accommodation at the South Pole, I’d talk to Atlas Copco, the leaders in artificial snow, and combine their technique with a snow thrower (which I imagine would already be available on site).
An inflatable building of the type used throughout sub-Arctic and Arctic countries as ice-hockey halls would make an excellent mould; it’s even the right shape for an ogive arch. Spray it with sufficient layers of semi-melted slush (no need to skimp), wait a couple of hours and there you are. Deflate the hall, pull it out and spray the next dome. Erect as many as needed to provide ample space for everything, including enough recreation (ice hockey?) to keep cabin fever at bay.
The easiest way to use such artificial ice domes would be to place small conventional buildings inside, as in the present aluminium dome. There are two options: either maintain about 鈭�2 掳C around the buildings and room temperature inside them, or insulate the whole dome and maintain a shirtsleeve environment throughout. The easy way to do that is to place the insulation on the mould before spraying the dome. Spray urethane foam before the slush, maybe.
Incidentally, ice domes would be semi-transparent, and would provide reasonable daylight for six months of the year. The rest of the time there would be exactly what the windows in the fancy stilt cabins would provide, namely darkness.
Light barrier
What G眉nter Nimtz’s argument overlooks is that stacking together a chain of prediction processes, each of which works fairly well over a short period of time, does not necessarily generate a good long-term prediction (“Faster than the speed of light”, 1 April). In fact, the waveguide he postulates would not deliver a recognisable signal at all, let alone a signal travelling faster than light.
I would make Raymond Chiao and Aephraim Steinberg’s points a little differently, and say: what stops you sending a signal faster than light is that the laws of physics (as currently understood) forbid this; what makes you think that you can under certain conditions do this is that it is possible to predict the future to a limited extent, and a system that makes use of such predictive possibilities can fool you into thinking that information is travelling faster than it actually is.
I feel Einstein’s barrier has not been broken. He has said that nothing can exceed the speed of light. The new speeds given for photons which have succeeded in quantum tunnelling are in excess of the current value for the speed of light in air, but they are still light photons. So clearly, the case still holds that we are dealing with the speed of light 鈥� only faster light. The discovery only throws more “light” on the bizarre and relatively unknown quantum world.
Doubtlessly, upon looking at the cover date of the issue referred to, an army of Trekkies will descend upon your offices shouting angrily about “sick senses of humour” or other less polite remarks. This is probably just one of many letters or faxes you have received on this subject, but 鈥� nice joke. It even had me going, and I consider myself to be cynical.
Or is this some kind of joke in reverse? Is this story actually true, and yet no one has believed it? While I suspect that this is a joke of some kind, I hope that the truth will out. One way or the other.
The joke was that it wasn’t a joke 鈥� Ed
Under the loo
On page 10 of your supplement “The world below” (1 April) you refer to the site of the telephone exchange under Chancery Lane tube station, which you say now stands empty and unused. Perhaps.
Three or four years ago the high hoardings came down from around the public lavatories in the middle of Holborn just east of the station entrance. The ostensible refurbishment had taken more than three years, a lot of heavy equipment, and sometimes up to 80 men (I used to count them out in the evening from time to time). Casual enquiries about progress with the loos met with stony silence, until it was suggested rather urgently that I stop enquiring; so I did.
That is also the reason for the anonymity of this letter, but there are many shops and offices nearby, and I am sure anyone interested could obtain confirmation from people who were in the area at the time. You might also visit the loos after the expensive refurbishment; you may be surprised.