Jake Garn the senator and astronaut is now also Jake Garn the novelist.

He is co-author of a "techno-thriller" titled "Night Launch" about a space shuttle flight that becomes hijacked.The book, co-written by Stephen Paul Cohen and published by William Morrow in New York City, is scheduled for release on April 24, and publicity about the book is to begin in earnest next week, the publishing company said.

Garn declined an interview about the novel until after his publisher begins his publicity drive.

Aides to Garn said the novel aims to deal in a realistic way with how a space shuttle could be hijacked and the consequences.

They said their understanding of the story line is that an East German astronaut who is part of a regular shuttle mission is secretly also loyal to an extremist group and hijacks the shuttle on its behalf.

Supposedly, both the United States and the Soviet Union suffer because of the hijacking.

Garn - a staunch defender of the space program - flew as a "congressional observer" on the Discovery in 1986. He was at the time chairman of the appropriations subcommittee that oversaw NASA's budget.

Garn has written magazine articles about his flight, and he is now incorporating his experience about the space program into the novel.