Tripoint Tripoint is a science fiction novel written by the United States science fiction and fantasy author C. J. Cherryh, and was first published by Warner Books in September 1994. It is one of Cherryh's Merchanter novels and is set in the author's Alliance-Union universe.

In the Alliance-Union universe, Tripoint is a system of three "dark" masses orbiting each other. They are not composed of dark matter; rather, they are much less luminous than a star. Two of the points are brown dwarfs, and the third may have been captured later. It was first charted and navigated in 2266, and serves as a staging jump-point on some of the commercial station-to-station hops, for example, PellViking and Pell–Mariner. Tripoint's orbital behavior is troublesome to predict due to gravitational interactions of three massive bodies; thus, navigation is challenging in the vicinity.

It's one of the so called Merchanter novels. These science fiction novels explore the merchanter subculture: the extended families that own and operate the ships that supply goods, transportation, news and trade to the various worlds and space stations in the human Earth, Alliance and Union space.

The merchanter-oriented works include:

Merchanter's Luck (DAW Books, 1982)
Rimrunners (Warner Books, 1989)
Tripoint (Warner, 1994)
Finity's End (Warner, 1997)

All four books were nominated for the Locus Award for Best Science Fiction Novel in their respective years of eligibility, but only Rimrunners and Finity's End were shortlisted. Cherryh's Hugo Award-winning novel Downbelow Station (DAW, 1981), is also closely related to these works, as it covers the conclusion of the Company Wars between the Earth Company Fleet and Union, and the formation of the Merchanter's Alliance itself.

The books are works of space opera, and some also have aspects of military science fiction, particularly Rimrunners.

Wikipedia: Merchanter Novels, Tripoint,