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24 March 2012 | NewScientist | 33

that is the subject of the article. We would normally try to avoid such terminology in New Scientist.

Library of the futureFrom David Holdsworth, Leeds UniversityBob Holmes explored what clues the archaeologists of AD 100,000 would unearth in the absence of a written record (3 March, p 48). But that record will not be absent in 100,000 years, so long as

technological civilisation endures.I am among those looking at the

survival of today’s written record, the vast majority electronic. We have worked out how to preserve it indefinitely, with perfect digital copies. As we copy onto newer forms of storage, the volume shrinks spectacularly, so physical storage is not a significant problem. There remains the question of understanding the formats in which material is recorded. This is being addressed by registries of how different formats store data.Settle, North Yorkshire, UK

The editor writes:n We covered these issues in the feature “Now we know it…” (30 January 2010, p 36)

Time after timeFrom Geoffrey SherlockThomas Smith asks about jet lag and judgement (18 February, p 33). Some years ago, while making a

descendants may well have to come to terms with never having the means or lifespan to reach other stars” (3 March, p 45).

The means is one thing, but the lifespan is another. Accelerating (and decelerating) at just 1g – emulating Earth’s gravity – would allow a human to get a fair way across our galaxy during their lifetime, because relativistic time dilation means that time on-ship is not the same as on Earth. If I had the right spaceship, I could travel to our neighbouring star Proxima Centauri and back. Of course, a much longer time will have elapsed on Earth, but that’s beside the point.Nottingham, UK

From Denis WatkinsWith “God, gold or glory” as motivation for the exploration of the world by Europeans from the

17th century onwards, and in view of our culpability for the wholesale extinction of species that is allied to the plundering of the Earth, perhaps the quarantine of humans to the solar system is for the best.Velindre, Pembrokeshire, UK

Knew you’d say that?From Mark ColsonIf statistically significant precognition existed, that would be stunning – even at the level of 2.27 per cent that Michael Franklin reports (14 January, p 38).

Presumably this figure is the mean for the test population. But

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For the recordn Ötzi the iceman had trouble with lactose digestion (3 March, p 10): lactose is milk sugar, not a protein.n In our story on treating late-stage Alzheimer’s (10 March, p 5), we should have said Clive Ballard is director of research at the Alzheimer’s Society.n The Nuclear Advanced Manufacturing Research Centre has asked us to point out that work on developing materials for a new generation of nuclear power stations by Mike Burke and Tim Abram (10 March, p 44) is the responsibility of the Dalton Nuclear Institute at the University of Manchester, UK. Also, Tim Abram is not a member of the Nuclear AMRC.n Our story on a drug that targets a bacterial communication enzyme should have said it was as effective against the 26th generation of bacteria as against the first (10 March, p 14).

what is the spread of individual performances? In other words, does everyone have this weak ability, or do most of us not have it, while a few special beings are incredibly gifted? This letter will be of little interest to them: they will have already “felt” it.Highton, Victoria, Australia

Michael Franklin responds:n I am currently working under the assumption that precognition is akin to unconscious perception. Psychologists have come up with clever ways to demonstrate the existence of unconscious information and this is the approach used in my experiment. Despite the weak signal, my results suggest that under the right conditions anyone could demonstrate precognition. However, that precognitive information need not be explicit, or available to them.

On disorderFrom Brian HortonThe article on rewriting the autism rule book by Fred Volkmar and Francesca Happe (10 March, p 30) kept referring to Asperger’s as a disorder. We prefer to use Asperger’s syndrome, since the term disorder implies that there is something wrong.

It is not necessarily any more a disorder than being left-handed, which is mainly a disadvantage because the world is built for right-handers, but being a leftie can be an advantage in certain sports and may be of benefit in other areas.

Aspies have an advantage where logical thinking is required, and so they perform well in areas such as science, engineering and computing.West Launceston, Tasmania, Australia

The editor writes:n Disorder is the word used in the current edition of the DSM, the US diagnostic guide for psychiatry

programme on time zones for BBC School Radio, I interviewed a senior medical officer at British Airways. She told me of a working rule that for every 1-hour shift of time zone during a flight, crew and passengers should have 24 hours’ rest before making any important decisions.

She realised this was impossible in reality: but it stressed that our body clocks can be disturbed by rapid time changes and that the effects could be disastrous, especially for world leaders rushing from conference to conference worldwide. This could explain many of our problems.Amersham, Buckinghamshire, UK

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