Wikipedia
Spaceopoly
Spaceopoly, a simplified version of Solarquest, was first published in 1997 by Valen Brost Game Co.
Your mission in this Monopoly-like game is to build monopolies within the planet systems and complete a special assignment while avoiding bankruptcy and the many perils of space travel.
Despite the name, Spaceopoly does not use the traditional Monopoly board setup. Rather, the board represents the solar system, including the gravitational pull of the various planets.