Where does the moon come from?

Whether we’re trying to find out where it came from, or how to siphon off some of its energy, grappling with the moon is harder than it looks.

When the Apollo astronauts brought back pieces of lunar rock, the samples promised to answer the question of the moon’s origin. It’s a question we are still asking.

The “big splash” theory of a gargantuan collision between two planets is the favourite. The idea is that a Mars-sized object hit the young earth, throwing off a load of matter which coalesced to form the moon.

Scientists became convinced that the big splash theory must be correct because it calls for the stuff in the moon to be lighter than the atoms making up earth. Initial analysis of the relative abundance of various forms of atoms (known as isotopes) in the Apollo samples provided supporting evidence.

However, researchers then thought to take account of the effects of a few billion years of bombardment by high-energy subatomic particles called cosmic rays. Because earth is protected from cosmic rays by its magnetic field, these would change the moon’s isotope abundances only and in particular ways. Unfortunately, all this has been a dampener on the big splash theory.

Other theories are available. The moon could simply have formed independently at the same time as the earth, for instance. Or it could have been a passing body that fell into our planet’s gravitational field and got trapped.

Most planetary scientists remain convinced that the big splash is right but to convince themselves and others they have to work out a consistent story. That’s why they gathered to sift through all the evidence at the Royal Society in London on 23 and 24 September.

Despite the lack of consensus, scientific achievements in this area are astonishing. We are narrowing down the timings of events that occurred 4.5 billion years ago. Some of the research that was presented showed that the moon is roughly 100 million years younger than we had thought. This kind of forensic analysis of vaporised rock is an extraordinary feat.

If only our progress in harvesting lunar energy was as extraordinary. Most experts are convinced that there is a way to profit from the moon’s gravitational pull on the oceans, but the devil is in the detail.

The Scottish government recently gave the go-ahead for the Pentland Firth to host Europe’s largest tidal energy project. It is estimated that the Pentland Firth could eventually meet half of Scotland’s electricity needs, but for now engineers are aiming to have 40 per cent of homes in the Scottish Highlands running off lunar power by 2020.

In many ways, it’s a great leap forward. Yet meeting 40 per cent of the needs of one of the UK’s less inhabited regions also seems a little underwhelming. One of the benefits of being a small island is that Britain has copious tidal and wave power at its disposal: enough to meet a fifth of our electricity needs.

Whether we’re trying to find out where it came from, or how to siphon off some of its energy, grappling with the moon is harder than it looks.

A 'Super Moon' rises over Sydney. Image: Getty

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 07 October 2013 issue of the New Statesman, The last days of Nelson Mandela

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Not just a one-quack mind: ducks are capable of abstract thought

Newborn ducklings can differentiate between objects that are the same and objects that are different, causing scientists to rethink the place of abstract thinking.

There’s a particular loftiness to abstract thought. British philosopher and leading Enlightenment thinker John Locke asserted that “brutes abstract not” – by which he meant anything which doesn’t fall under the supreme-all-mighty-greater-than-everything category of Homo sapiens was most probably unequipped to deal with the headiness and complexities of abstract thinking.

Intelligence parameters tail-ended by “bird-brained” or “Einstein” tend to place the ability to think in abstract ways at the Einstein end of the spectrum. However, in light of some recent research coming out of the University of Oxford, it seems that the cognitive abilities of our feathery counterparts have been underestimated.

In a study published in Science, led by Alex Kacelnik – a professor of behavioural psychology – a group of ducklings demonstrated the ability to think abstractly within hours of being hatched, distinguishing the concepts of “same” and “different” with success.

Young ducklings generally become accustomed to their mother’s features via a process called imprinting – a learning mechanism that helps them identify the individual traits of their mothers. Kacelnik said: “Adult female ducks look very similar to each other, so recognising one’s mother is very difficult. Ducklings see their mothers from different angles, distances, light conditions, etc, so their brains use every possible source of information to avoid errors, and abstracting some properties helps in this job.”

It’s this hypothesised abstracting of some properties that led Kacelnik to believe that there must be more going on with the ducklings beyond their imprinting of sensory inputs such as shapes, colours or sounds.

The ability to differentiate the same from the different has previously been used as means to reveal the brain’s capacity to deal with abstract properties, and has been shown in other birds and mammals, such as parrots, pigeons, bees and monkeys. For the most part, these animals were trained, given guidance on how to determine sameness and differences between objects.

What makes Kacelnik’s ducklings special then, as the research showed, was that they were given no training at all in learning the relations between objects which are the same and object which are different.

“Other animals can be trained to respond to abstract relations such as same or different, but not after a single exposure and without reinforcement,” said Kacelnik.

Along with his fellow researcher Antone Martinho III, Kacelnik hatched and domesticated mallard ducklings and then threw them straight into an experiment. The ducklings were presented pairs of objects – either identical or different in shape or colour – to see whether they could find links and relations between the pairs.

The initial pairs they were presented served as the imprinting ones; it would be the characteristics of these pairs which the ducklings would first learn. The initial pairs involved red cones and red cylinders which the ducklings were left to observe and assimilate into their minds for 25 minutes. They were then exposed to a range of different pairs of objects: red pyramid and red pyramid, red cylinder and red cube.

What Kacelnik and his research partner found was that the ducklings weren’t imprinting the individual features of the objects but the relations between them; it’s why of the 76 ducklings that were experimented with, 68 per cent tended to move towards the new pairs which were identical to the very first pairs they were exposed to.

Put simply, if they initially imprinted an identical pair of objects, they were more likely to favour a second pair of identical objects, but if they initially imprinted a pair of objects that were different, they would favour a second pair of differing objects similar to the first.

The results from the experiment seem to highlight a misunderstanding of the advanced nature of this type of conceptual thought process. As science journalist Ed Yong suggests, there could be, “different levels of abstract concepts, from simple ones that young birds can quickly learn after limited experience, to complex ones that adult birds can cope with”.

Though the research doesn’t in any way assume or point towards intelligence in ducklings to rival that of humans, it seems that the growth in scientific literature on the topic continues to refute the notions that human being as somehow superior. Kacelnik told me: “The last few decades of comparative cognition research have destroyed many claims about human uniqueness and this trend is likely to continue.”