James S. A. Corey "Abaddon's Gate" PDF

For generations, the
solar system -- Mars, the Moon, the Asteroid Belt -- was humanity's
great frontier. Until now. The alien artifact working through its
program under the clouds of Venus has appeared in Uranus's orbit, where
it has built a massive gate that leads to a starless dark.
Jim Holden and the crew of the Rocinante
are part of a vast flotilla of scientific and military ships going out
to examine the artifact. But behind the scenes, a complex plot is
unfolding, with the destruction of Holden at its core. As the emissaries
of the human race try to find whether the gate is an opportunity or a
threat, the greatest danger is the one they brought with them.