From what I understand, all points on Earth receive the same electromagnetic wave pattern from a particular quasar, because quasars are very far away. See this comment:https://www.schneier.com/blog/archives/2006/03/quasar_encrypti.html#c50809
Quasars are so small (point-like, diameters of milli-arcseconds) that their noise emissions are highly correlated when viewed across terrestrial baselines in the microwave range.
As such, I was thinking that it might be useful to the Ethereum protocol. For example, in proof of stake, the selection of a validator for a block can be determined by the random number generated by a set of quasars. Assuming the above assumption about the EMR of a quasar holds true, this would be a globally uniform and un-gameable source of randomness.
The quasar random numbers could also be used as an objective timestamp, to provide the network with a time-keeping mechanism. I'm not sure what uses this could have, but I imagine it might be useful for liveness denials.
While not needed for the currently proposed Proof of Stake algorithms, it's also worth considering that Ethereum mining nodes could be required to include the random number generated by quasars in a given time interval, in the block that they are mining, in order to prevent geographical clustering of mining nodes.
If the pre-agreed set of Quasars surround Earth, every node would have to wait exactly as long as every other before beginning work on the 'next block', because they would have to wait at least as long as it takes for the last wave pattern in the time interval from the Quasars that are closer to the opposite side of Earth to be transmitted via an electromagnetic signal to their side of Earth.
Since every point on Earth would have some Quasars that are closer to the side of the Earth opposite them, that means all points on Earth would need to wait the same amount of time to receive the full wave pattern of all the Quasars in the set.
Anyway, all of this is all very pie-in-the-sky type stuff, but interesting enough that I thought I'd share.