Star Trek: Mere Anarchy

Mestiko: a world on the brink of interstellar space travel--and under covert Federation observation. When the Payav, Mestiko's dominant nation, learns of a rogue pulsar sweeping through their star system and threatening to destroy all life on their planet, the Federation is faced with a daunting choice: stand by and witness the extinction of a thriving civilization, or violate the Prime Directive and mount a desperate effort to protect the planet from total devastation.

The Starship Enterprise, newly under the command of James T. Kirk, is sent to aid the doomed planet. Kirk and his officers--Spock, Mitchell, Kelso, Scott, Sulu, and Dr. Piper--must use an experimental, untested technology to save the planet before it's too late!