Any way to make your crew stop attacking a system?
I've been in a similar situation, and no, there is no way to stop them attacking. I've always wondered what goes through their heads in these situations. Probably something like this:
Me: "No, stop attacking, one more hitpoint and that ship'll be torn apart!"
<Mantis 1 turns to Mantis 2>
M1: "We have a chance here to do something great, something profound here today"
M2: <Smiles Grimly> "I hope the Federation dedicates a statue on some blasted rock for us"
<They embrace>
M1: "It has been good knowing you brother"
<They turn and deal the final blow to the shield generator. As the ship blows up around them they look out a nearby window and see the Kestrel - dodging past a few missiles as a Beam Drone continually attempts to break through the shields, and they know that their sacrifice will be remembered.>