I haven't yet fully read the third part of the book, but I had a hard time to suspend my disbelief when it comes to resources - given the story is sold as hard sci-fi.

They land on the Cleft with what's left of Izzy and a few Arklets some of which are exclusively used for storage. I understand that they have access to almost unlimited metal from the Cleft as well as water and other substances from asteroid mining, but AFAIK plastic comes from oil which they don't have access to and plastics are a huge part of our life.

So it's pretty hard to swallow that they survive for 4500 years with the finite resources brought in a few cans.

So My question is: How did they survive for 4500 years?

Am I missing something?

3 Answers 3


Plastic, I would say, is among the least of their worries. By the time they land on Cleft, they have limited amounts of all types of consumables, especially water and food. In the extended short term, they can manage to sustain a very small population through a very efficient recycling process, but the fact remains that Izzy and the Arklets brought effectively jack squat when you look at the prospect of building an advanced society in the hundreds of millions.

[by the way, I've always understood Cleft to be (part of) the solid core of the Moon; if so, they might be short-strapped for metal variety as well, given how the solid core of the Moon is mostly a large chunk of iron with tiny deposits of nickel and sulfur]

There are some clues in Part 3 of the book. There are a couple of places where they mention how, after the Hard Rain started to abate, they replenished the oceans by altering the orbits of ice comets. This hints that they retained a notable knowledge about space travel and civil engineering. It is not a stretch to think that they used the same technology to harvest things they needed (water, metals other than iron, certain naturally-occurring compounds, etc) from elsewhere in the Solar System.

With respect to your specific question, plastic is ubiquitous in our current world largely because it is cheap and easy to produce in very large quantities. I'm looking around my office right now and I really can't find that many things made out of plastic that would lose their functionality if they were built out of something else. A society with only small amounts of plastic would be different, but not necessarily worse, let alone dysfunctional.


Plastics are primarily hydrocarbons (i.e. compounds of carbon and hydrogen). Given enough energy and the right equipment you can synthesize them from the elements. Izzy is mostly water, but probably has quite a few other elements mixed in. They can also go outside the Cleft and get rocks from the rest of the fragmented moon, albeit at some risk.


Plastics have been around less than 200 years making do without plastic or low quality plastic as you would get from multiple rounds of recycling isn't that big of a problem.

AFAIK plastic comes from oil

Traditionally plastic comes from oil, but no one said it had to be dinosaur oil, vegetable oil can also be used to make plastic. Other things like cellulose and starch can be used to make plastic as well. There have also been bacteria that have been genetically engineered to produce plastic. They have several options for plastic without dragging an oil field along with them.

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