The light that is greeting you right now is seven minutes old. That’s how long it takes for it to travel from the Sun to earth.
From Mars, it can be as much as 24 minutes depending on how far it is as it circles around the sun.
Getting the block data from Mars to earth therefore is not necessarily difficult, but getting it within 10 minutes is probably impossible.
That means ethereum can not play here in the interstellar crypto stock market due to its 15 seconds blocks, and neither can bitcoin in its current form.
Yet there are ways to get them both to facilitate interstellar commerce, and quite a few ways.
One of them would be to simply change block times to one hour or even 30 minutes for the Mars blockchain.
Then the speed of light latency wouldn’t be a barrier with the martians and earthlings able to keep in sync as Mars based miners compete with earth ones for new bitcoins.
Waiting 30 minutes may be a bit much however, especially if you’re going to do defi transactions where martians and earthlings can participate at an equal level.
Just imagine waiting 30 minutes for the execution of a decentralized exchange (dex) order while centralized exchanges move at an almost instant speed because the speed of light is very fast, one nanosecond per feet (0.3 meters).
So Blockstream came up with an April Fools joke of launching a sidechain network where the martians can transact with bitcoin, but in their own blockchain network that at times then connects to the bitcoin blockchain network.
“Users wishing to test out the Lava Network should remember to download Blockstream Red before leaving the Earth’s gravitational sphere of influence. Once in low Martian orbit, or upon arrival on the Mars surface, open the Blockstream Red app, connect to your Satellite Receiver via Bluetooth, and start making some interplanetary transactions,” they said very jokingly.
Yet this sidechain connection could potentially work and with ethereum you can also have it natively through a contract level settlement network whereby martians bundle their own transactions and then settle on the ethereum blockchain at the speed of light or thereabouts.
So once we get there the blockchain should be able to keep us connected, but getting there is not an easy task although one achievable hopefully within our lifetime.