Aurora Rising by Amie Kaufman & Jay Kristoff

The year is 2380, and the graduating cadets of Aurora Academy are being assigned their first missions. Star pupil Tyler Jones is ready to recruit the squad of his dreams, but his own boneheaded heroism sees him stuck with the dregs nobody else in the Academy would touch…

A cocky diplomat with a black belt in sarcasm
A sociopath scientist with a fondness for shooting her bunkmates
A smart-ass techwiz with the galaxy’s biggest chip on his shoulder
An alien warrior with anger management issues
A tomboy pilot who’s totally not into him, in case you were wondering

And Ty’s squad isn’t even his biggest problem—that’d be Aurora Jie-Lin O’Malley, the girl he’s just rescued from interdimensional space. Trapped in cryo-sleep for two centuries, Auri is a girl out of time and out of her depth. But she could be the catalyst that starts a war millions of years in the making, and Tyler’s squad of losers, discipline-cases and misfits might just be the last hope for the entire galaxy.