Portal (Boundary #3) by Eric Flint and Ryk E. Spoor

Science Fiction/Space Opera

What Goodreads says:

"Madeline Fathom had miraculously landed the crippled Nebula Storm on Europa. She joined on that frozen moon of Jupiter the stranded crewmembers of the ill-fated EU vessel  Odin. The Nebula Storm's reactor was ruined in the landing, the Odin’s shuttle can’t make the trip back home, and the only vessel that could have make the journey to save them has just been destroyed by a renegade crewman, bad luck, and the remorseless forces of nature.

But Madeline, Helen Sutter, A.J. Baker and the team have one card left to play. All they have to do... is survive lethal radiation, vacuum, and ice as hard as steel while they figure out how to make  Nebula Storm fly again.

But even as they prepare to make the journey home, Europa has one more discovery waiting for them... a discovery that might be the deadliest trap in the Solar System!"

If you have read the Boundary series from book one you don’t want to miss reading Portal.  If you have not read the series from book one start do not start with Portal.  Why:

Backstory:  All of it is in the previous books.  This picks up directly after the end of book 2 and while there are hints about what happened before they would be more confusing than enlighting if you had not read the previous books.

Worldbuilding:  Same as backstory.  Most of the worldbuilding was done in the previous books.  You know it is the future but without the backstory the world might not be that plain.

Characters:  There is some character development.  Most of the characters have been part of the story in the previous books and they their development was done then.  Many have some unique traits that might seem strange if you are meeting them for the first time.

Plot:  Book two left them in a big fix.  Getting home is the focus of the book with some additional plot features added.

I sound like a broken record but Portal is for everyone who has read the previous two.  It is well written,  has a good story and is an enjoyable conclusion to the Boundary series.  It is not a good standalone book.

Baen published Portal by Eric Flint and Ryk E. Spoor in 2013.