IDW Publishing has released the solicitation for the third issue of Star Trek / Green Lantern: The Spectrum War which is set to see publication in September.  IDW will have a number of variant covers for the project.

Here are two of cover images released so far for the third issue and the solicitation information providing some plot details.

Star Trek/Green Lantern #3 (of 6)
Mike Johnson (w) • Angel Hernandez (a) • Tony Shasteen (c)
The blockbuster crossover event of 2015 continues here, as the galaxy explodes in a Lantern-fueled war between the Federation and its enemies! Captain Kirk and the ring-bearing crew of the Enterprise must join forces with Hal Jordan to prevent the loss of entire civilizations… as the identity of the villain behind it all is revealed!