Portal Authority Contract #3

Sometimes things you’ve left behind come back to haunt you.
Jonas Stone has a debt of honour to pay, and being the Captain of the Galactic Surveys starship James Cook is an installment on it. He’s taken two nuclear submarines into harm’s way, but all that is behind him now.
Ashley Hanson won the nickname of Gunslinger, the one who could make it happen when a Contract was in play and the clock was running on a planetary disaster. Gunslinger used people, and sometimes she used them up.
Gunslinger is in her past. She’s getting paid to be an astronomer, and just loving every minute of it. She has no idea why any sentient race would not study the universe they live in, but she’ll take the credit to do it for them.
When they stumble across an anomalous asteroid drifting in from interstellar space, they get a Contract they can’t refuse from the powerful enigmatic aliens who run the Portal network which binds the worlds of the Orion Arm together.
When is a von Neumann machine a Berserker? The Portal Aliens want the answer.
There are no excuses for not fulfilling a Contract, and she has taken The von Neumann Contract.