Momentum effects at a 100% ratio should do 0 block damage. Unfortunately astronauts don't count as "blocks" so the weapons do full damage on them.
This goes for all weapons (cannons/beams/missiles/pulse). Also the push pulse weapon damages astronauts.
How to reproduce:
- make a cannon/beam (easiest to aim with)
- link a momentum effect to it and make sure it is a 100% effect ratio
- shoot a NPC or a second client