Valkyrie: Expeditionary Force, Book 9

After saving the world many times, the Merry Band of Pirates have accepted the inevitable: Earth is doomed.

All they can do is try to bring a few thousand people to safety, before vicious aliens arrive to destroy humanity's home world. 

No. 

There is one other thing they can do: hit the enemy so hard that the aliens will regret they ever heard of humans.