I don't think it was specified what system the Galatea was in when you went to assist her.
If the good admiral had any sense, he would have turned that ship around and try to run for friendlier skies or towards more help.
Simply put, yes the mission is important, but you can't fullfill the mission if bombers waste your ship before you get there.
Personally I don't know why the Galatea was sent off with no ESCORT!
A fenris, a leviathan, a posiedon freighter armed with banshees, hell, even an aten!
(Sorry, really love that ship design, but facts are facts.)