Note: This is an opinionated answer.
I doubt block-chain, in the conventional sense where the Merkle root contains transaction (money) data, makes sense for spaceflight. It's a pump-and-dump operation that should've died a long time ago, but didn't because people use it to make money off of those who are stupid. The whole idea behind "mining" the verification on "transactions" would be cumbersome for hardware in space.
Impromptu Case-study: Block-chain for something other than money?
The only thing I could see is block-chain in a non-conventional sense (possible keep track of impulse maneuvers as if they were money), but it really doesn't make sense at our current scale. Take for instance if we had a large number of satellites, maybe a 1000 node cube-sat network (this is still a micro scale), and we really needed them to ensure that all the maneuvers (transactions) they've accomplished position themselves in accordance with the cube-sat swarm. Maybe, with every maneuver that each cube-sat makes sends a message to a handler earth-side, creating the transaction blocks, and creating a block-chain where each satellite could track the full impulse motions of all other satellites from launch to current state vectors.
Average Block Size 0.66 Megabytes The 24 hour average block size in MB. Transactions per Day 212,753 Transactions The aggregate number of confirmed Bitcoin transactions in the past 24 hours. Mempool Size 1,774,772 Bytes The aggregate size of transactions waiting to be confirmed.
Once again though, this requires computing power-- a lot of it, scaling up with every single day and every single maneuver added to the chain. While you can cache the block-chains after the first computation and do additive calculations to decrease complexity. This would require a lot of radiation hardened storage space that cannot deal with even a slight bit of corruption (block-chain caches are not radiation hardened).
On the plus side, however, you now have 1000 satellites that know where each other are, indefinitely. If one satellite goes down for awhile to the point where the memory is dumped (full power loss) attitude could be regained by reconnecting with the block-chain and calculating the cache again. This is just one example of a potential block-chain usage in space, I'm sure other people could come up with something much better. However, there are more conventional ways to fix attitude real-time (accelerometers, etc...). Usually the direct-math approach is better in terms of software complexity (time to execute) memory storage (how much you need to cache) and total efficiency. Why not just send the state-vectors of each satellite calculated from velocity as positioned from the stars cached every day?
I really think it circles back to the fact that we haven't yet seen a use for it. Other ideas like this may also be useful, but once again this is a macro concept; we're still on the side of a micro-spacex world.
Here's a Quora answer (yes I know, ew) about using Block-Chain in non-money situations:
It actually covers a lot of the true uses that have been appearing:
- Detecting voter fraud.
- Currency that doesn't require bureaucracy in times of crisis.
Mostly they've been shown as beneficial in areas where data is easily misrepresented-- like in scenarios with a lot of fraud, or ability for humans to "get their hands dirty". I guess this could extend to space to some degree, but in what ways I couldn't say.