Editor's pick: More than NASA depended on women
It wasn't just NASA that depended on the skills of women mathematicians (21 January, p 40). My mother, Dolores Guarneri Nelson, worked for General Electric in the 1950s on the liquid metal fast reactor for the USS Seawolf, the US's second nuclear submarine. She was tasked with setting up calculations to validate the engine design.
She had a degree from Purdue University, but engineering posts were not given to women so she was graded as an assistant and given a significantly lower salary. There was one African-American on the team; when they went to Washington for meetings, he had to stay in a different hotel.
She gave up work, as expected, when she started a family and so was unable to keep up with advances in software development. How far we have come, not just in technology but in equality of opportunity. I know I've been fortunate – society is by no means free of gender and race bias – but my daughters' response to their grandmother's stories is “Really? You've got to be joking!”
If I'm still not awake, then you're not real…
Frequently asking myself, “Is this a dream?” apparently allows me to do the same when asleep, providing a route into lucid dreaming (18 February, p 32). Mustn't I take care not to answer the question, though?
If I habituate myself to confirm I am not in a dream, won't I program myself to confirm I am not in a dream at all times?
But if I don't answer the question when awake, why should I expect myself to when asleep? Perhaps it is best always to tell myself that I'm in a dream… which I suspect to be the case anyway.
If I'm still not awake, then you're not real…
Before I knew about lucid dreaming, I taught myself some techniques to deal with nightmares. I simply make my mind blank in the dream, which leads me to wake up. Sometimes it is quite an effort, but it always works.
The most enjoyable part of a lucid dream, apart from the awareness that it is a dream, is explaining to people there that they are just figments of my imagination. They look at me, as they would in real life, as though I were barking mad.
This doesn't make the dream any less dream-like, but it does increase the entertainment value.
First class post
My dog woke up and looked around in confusion when I played that sound
Christine H on sounds birch caterpillars make with their anuses (4 March, p 19)
A space rose by another name smells sweeter
I am working on the HABIT instrument that will be part of the European Space Agency's ExoMars 2020 mission (18 February, p 7). I appreciate that naming space missions after great personalities in the history of science, such as Darwin, Galileo and Cassini, is a gesture of respect. But the recent crash of the ExoMars Schiaparelli module made me ponder whether we should avoid naming space missions after people.
We could celebrate them after the mission is operational, and use a provisional name until then. Contradicting Shakespeare, we should name the rose after the sweet smell of success.
Why should we flunk recycling space junk?
The cost of lifting things into orbit is so high that everything there is effectively made of gold. So why are we trying to send space junk into a decaying orbit to burn up (11 February, p 4)? Surely it would be better to launch a fabricating satellite that could gather the junk, refine it and make it into useful satellites? There is plenty of energy available up there, after all.
If the fabricating satellite made copies of itself, junk would be cleared at an exponentially increasing rate, and we would end up with a vast orbiting production capacity.
More than one can play at national security
You report US President Trump's executive orders reducing the powers of the Environment Protection Agency and restricting scientists with regard to climate change research (11 February, p 4). Can these actions not be challenged through the US courts as threats to national security? After all, the on the risk climate change poses on these grounds. Trump doesn't have to be the only one playing the national security card.
If the President then turned his invective on to the military as well as judges, scientists and parts of the media, that might not go down well with his core constituency.
It's a very local sea level and the drains don't fit
Laura Spinney mentions two reference datum points at which sea level is measured in the UK, at Newlyn and Belfast (11 February, p 38). There used to be a third, at Liverpool. The construction firm I worked for had a site in central London that crossed a boundary between two local authorities: one side was levelled to Newlyn and the other to Liverpool. The discrepancies made problems for the public health engineers trying to plan the drainage. This was obviously well known to the Ordnance Survey, who were able to supply a correction factor when given a grid reference.
Koalas should beware the wily goanna
Alice Klein reports observations of Australian foxes learning to climb trees (18 February, p 9). This is fascinating, but I think the threat to baby koalas and other arboreal life is overplayed. Monitor lizards, or goannas, which can exceed 2 metres in length, are at least as agile in trees as foxes, and every bit as voracious. Both are probably more interested in eggs and chicks than baby koalas.
Koalas should beware the wily goanna
A farmer here in Victoria told me 50 years ago of his difficulty in getting any cherries from his tree. “I went out one night to shoot the possum I thought was robbing the tree, and what fell on my head was a fox!” It had been eating the fruit. So their climbing trees is not new.
I have often seen fox scats full of plum stones or Crataegus seeds and also the remains of beetles and grasshoppers. They seem to be omnivorous.
Together, could baboons and orangutans talk?
You report that baboons have mastered vowels (14 January, p 12) and that orangutans can do consonants (17/24/31 December 2016, p 15). Surely now we have the answer to the mystery of human speech? Put them together and what have you got?
If music be the food of multitasking, play on
Emma Young's interesting report on speed-reading reminded me how easy it is to comprehend almost every article in 快猫短视频 (11 February, p 34). It also made me wonder whether there has been equivalent work on reading and playing music.
I am a chartered engineer who enjoys playing the piano outside of work. To do this I have to simultaneously read the dots, comprehend the instructions they indicate and apply my fingers accurately to the piano keys using both hands.
The score often has different keys, tempos and rhythms, including handfuls of chords in a single bar. A page of music has separate bass and treble staves (at least) and requires more eye movement than reading a line of text. It is clearly much easier to read when one is on “auto pilot” with an often-played piece, but there is no room for slowing down or speeding up while determining the best fingering pattern.
How does the brain manage such a collection of variables against the relentless ticking metronome?
The infinitesimally likely can happen at any time
Anil Ananthaswamy, suggesting we reject universes that lead to “cosmic brains”, rightly says that “there is always an infinitesimal probability that a system will suddenly fluctuate from disorder to order” (18 February, p 9). Then he quotes Sean Carroll saying that at 14 billion years old, our universe is too young for this to have formed Boltzmann brains.
The infinitesimal probability of this event occurring existed in the first nanosecond of our universe and in every nanosecond thereafter. You do not need an infinite time for the vastly improbable fluctuation to occur – you just need something with an infinitesimally small probability to have occurred.
Entanglement does not send messages
You say that particles' states “can be entangled – such that altering one affects the other much faster than light can travel between the two” (11 February, p 7). But you do not affect the other. Measuring some property of one determines the outcome of a measurement on the other.
In an experiment like the one described, you cannot say the measurement at A affected the photon at B: it would be just as valid to say the opposite.
So who passed the Affordable Care Act?
Marilyn Lott makes a valid point about calling the “Affordable Health Care Act” by its correct name (Letters, 11 February). But it was able to pass into law because, for a short period in 2008-2009, the Democratic Party held the White House, a majority in the House of Representatives and a super-majority – enough to stop filibustering – in the Senate.
For the record
• Boom! It would have been more precise to say that NASA's Quiet Supersonic Technology plane is designed to emit sonic booms 40 decibels quieter than Concorde's (25 February, p 34).