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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Pupils need internet classes? Here are 41 lessons they should learn

Forget privacy and security, here's what to do when a black and blue dress looks white and gold. 

It is imperative that children are taught how to survive and thrive on the internet, claims a new House of Lords report. According to the Lords Communication Committee, pupils need to learn how to stay safe, avoid addictive games, and become “digitally literate”.

It’s hard to argue with the report, which is a great step forward in acknowledging that the internet now basically = life. Yet although it is crucial that children learn how to stay private and secure online, there are also some equally crucial and not-at-all-flippant pieces of information that the youth urgently need to know. Here are the first 41 lessons in that curriculum.

  1. To figure out how much to donate towards your mate’s charity half-marathon, half X OR double Y, where X is the amount paid by their mum and Y is the amount donated by your closest rival, Becky
  2. Don’t mention that it’s snowing
  3. If – for some reason – you talk about bombs in a Facebook message, follow this up with “Hi Theresa May” in case Theresa May is looking, and then Theresa May will think you are just joking
  4. If you are on a train and you are annoyed about the train, do not tweet @ the social media manager who runs the account for the train, because they are not, in fact, the train
  5. If a Facebook meme starts “Only 10 per cent of people can get this puzzle right” – know that lies are its captain
  6. It’s not pronounced me-me
  7. Never say me-me nor meem, for they should not be discussed out loud
  8. People can tell if you’ve watched their Instagram stories
  9. People can’t tell if you’ve waded back through their Zante 2008 album and viewed all 108 photos
  10. People can tell if you’ve waded back through their Zante 2008 album and viewed all 108 photos if you accidentally Like one – in this circumstance, burn yourself alive
  11. Jet fuel can melt steel beams
  12. If a dog-walking photo is taken in the woods and no one uploads it; did it even happen?
  13. Google it before you share it
  14. Know that Khloe Kardashian does not look that way because of a FitTea wrap
  15. Do not seek solace in #MondayMotivation – it is a desolate place
  16. Respect JK Rowling
  17. Please read an article before you comment about a point that the article specifically rebutted in great detail in order to prepare for such comments that alas, inevitably came
  18. Don’t be racist, ok?
  19. Never, under any circumstances, wade into the Facebook comment section under an article about Jeremy Corbyn
  20.  If a dress looks white and gold to some people and black and blue to some others, please just go outside
  21. Open 200 tabs until you are crippled with anxiety. Close none of the tabs
  22. Despite the fact it should make you cringe, “smol puppers” is the purest evolution of language. Respect that
  23. Take selfies, no matter what anyone says
  24. Watch Zoella ironically until the lines of irony blur and you realise that the 20 minutes you immerse yourself into her rose-gold life are the only minutes of peace in your agonising day but also, what’s wrong with her pug? I hope her pug is ok
  25. Nazi Furries are a thing. Avoid
  26. Use Facebook’s birthday reminder to remember that people exist and delete them from your Friends list
  27. When a person you deleted from your Friends list inexplicably comes up to you IRL and says “Why?” pretend that your little cousin Jeff got into your account
  28. Don’t let your little cousin Jeff into your account
  29. “Like” the fact your friend got engaged even if you don’t actually like the fact she is reminding you of the gradual ebbing away of your youth
  30. No one cares about your political opinion and if they act like they do then I regret to inform you, they want to have sex with you
  31. Please don’t leave a banterous comment on your local Nando’s Facebook page, for it is not 2009
  32. Accept that the viral Gods choose you, you do not choose them
  33. Joke about your mental health via a relatable meme that is actually an agonising scream into the void
  34. Share texts from your mum and mock them with internet strangers because even though she pushed you out of her vagina and gave up her entire life to help you thrive as a person, she can’t correctly use emojis
  35. Follow DJ Khaled
  36. Decide that “Best wishes” is too blah and “Sincerely” is too formal and instead sign off your important email with “Happy bonfire night”” even though that is not a thing people say
  37. If someone from primary school adds you as Friend in 15 years, accept them but never speak again
  38. The mute button is God’s greatest gift
  39. Do not tell me a clown will kill me after midnight if I don’t like your comment because that is not a promise you can keep
  40. Don’t steal photos of other people’s pets
  41. Accept that incorrect "your"s and "you’re"s are not going anywhere and save yourself the time 

Amelia Tait is a technology and digital culture writer at the New Statesman.