Why not replace bitcoin’s proof of work with proof of astrophysics

18.22, Friday 24 Sep 2021

Cryptocurrency is interesting, may precipitate the collapse of civilisation, and is extremely troubling re: carbon.

Interesting because: NFTs allow rights (such as ownership but not exclusively) to be attached to digital objects; crypto techniques underpin a newly centralised internet swept free of gatekeepers from identity, to payment, to data centres.

May precipitate collapse because: the centralisation of handling money has led to giant and powerful financial institutions, and the decentralisation of money smells like the shift from centralised bronze production (which led to captured trade routes and giant palace kingdoms) to decentralised iron, arguably leading to the Late Bronze Age collapse, as previously discussed. LOOK: I don’t honestly think we’ll see a collapse of civilisation, but the banks may well reconfigure to become smaller and more numerous. Besides I find a potential decentralisation of energy production more fundamental and intriguing.

Extremely troubling: cryptocurrency takes a lot of electricity to run. And that creates a lot of carbon. Really not good.

Crypto is underpinned by a technique called proof of work (PoW) and I understand that this is the troubling carbon bit that needs to be replaced?

Hand-waving alert, obv. I’m not close enough to crypto to understand, but if I give the broad outlines of what I mean then someone else may fill in the gaps…

Proof of work relies on some mathematical technique which is hard to figure out for the first time, but then easy to verify. For example:

  • A hashing algorithm generates essentially a random number from a known starting number (it’s the same each time for a giving starting number). This is quick and cheap
  • Some hashes will be rare, say ones that start with the number “99”. So finding a starting number that leads to a rare hash requires running the algorithm a bunch of times. This is slow and expensive (and produces a bunch of carbon because it uses electricity)
  • So finding a rare hash is expensive to do but cheap to check.

I don’t entirely understand how this ladders up to consensus over an entire transaction history, as recorded in the shared blockchain, but a technique like this is key.

Because of the essentially wasted electricity and carbon cost, there are a couple of other replacement techniques being mooted, instead of crunching numbers.

  • Transactions are verified by parties with authority – let’s say central banks. Well that seems counter to the decentralised nature of the beast.
  • Transactions are verified by parties with skin in the game, ie wealthy people. This is called Proof of Stake and it sounds like it just puts the power in the hands of the rich.

Neither seems like a solution in the spirit of cryptocurrency. So what is to be done?


Replace the Proof of Work function with something which follows the exact same form (expensive to perform, cheap to verify: a zero-knowledge proof) but that outgasses socially useful work as a side-effect instead of carbon.

But what should it be?

Scientific conferences in pharma versus astronomy, the difference:

Pharma conferences are full of scientists playing their cards close to their chest. They don’t want to give even the tiniest hint about their research because somebody else, knowing what is being chased down, could get there first. So they don’t talk about their work or what they’re trying to figure out.

Astro conferences, on the other hand, are free and open. Seen a weird blob in the sky that might be a novel black hole or an alien superstructure? Show everyone the printout of the telescope image, it doesn’t matter! The night sky is so colossally huge that nobody will ever be able to find the same spot without you telling them the coordinates. And without knowing that, they can’t publish so your research is safe.

(I can’t remember who shared this anecdote with me, sorry.)

What I learn from this:

  • Pointing a telescope at the night sky is a essentially hashing algorithm. Give the telescope coordinates, you get back a random but consistent constellation of stars.
  • Hunting to discover a constellation that matches a particular, rare pattern (say: an equilateral triangle between the three brightest stars in the square) would be hard and slow.
  • But verifying that given coordinates lead to a given constellation is easy (or at least, as easy as pointing a telescope).


What if… looking at the night sky is a drop-in replacement Proof of Work function?

The side-effect of loads of crypto miners scraping the night sky with telescopes won’t be carbon, it will be a map of the stars.

That hyper-detailed and growing map of the stars becomes a public resource for scientists to better understand the cosmos, and also increases our chance of spotting aliens.

Currently crypto miners are incentivised to re-activate coal power stations to get electricity. Now they’ll be incentivised to fund new space telescopes instead.

Bonus: the current crypto PoW method has the concept of “difficulty” built in, and it is ramped up over time basically to account for computers getting faster. With telescopes you can increase difficulty by requiring that you look at smaller and smaller patches of sky. It takes longer to collect the photons to see fainter stars, or it requires building new and larger telescopes, both of which correspond to increasing difficulty parameters.

Caveat: I clearly don’t know what I’m talking about.


could we invent new underpinnings of cryptocurrency that pump out social good, rather than pumping out carbon? It would be good to assemble a committee of smart people to figure that out.

In the meantime we could just get started. NASA and SETI should create a coin. The James Webb Space Telescope (Hubble replacement) launches in December. Dedicate an hour a day of telescope time to this crypto project (for pay) and fund the development of the next telescope with the proceeds.

Let’s power the new global financial machine by searching for extra-terrestrials.

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