On page 83 of the Core rulebook, Bonus Momentum is defined as special momentum that is generated by some situations and Talents upon a successful Task of that type. Sometimes it is only useful for specific purposes, such as adding to damage or for Obtain Information.
This Bonus Momentum cannot be saved – if it is not used, it is lost.
This has created some confusion among GM and players alike. At my table, I will now be using a different Momentum token type to indicate Bonus Momentum when we are tracking Momentum use.
But which situations and Talents generate this special Bonus Momentum?
Here is a guide that I hope will help. Core Rulebook instances are indicated by bold, while sourcebook Bonus Momentum situations are indicated in italics.
EDIT: Antoine Lavoisier reminds me that extra Ship Power can generate Momentum as well (as on page 216). I’m not sure if that counts as ‘Bonus Momentum’ though. I’m seeking clarification.
EDIT 2: Nathan Dowdell confirms it should be treated as Bonus Momentum. It’s not on the current chart but I will add it in the near future.