Lyapunov's Climate and Geology

Density: 0.817x Earth (4.5 g/cm^3)
Mass: 0.65x Earth
Radius: 0.92661x Earth (5910km)
Gravity: 0.767 G
Rotation Period: 0.405 days = 9 hours 43 minutes 12 seconds
Moons: 3. All are small asteroids. Outermost moon's orbit is unstable.

Lyapunov is a planet orbiting a wide binary of sun-like G stars, somewhat smaller than Earth that had previously harbored a constant glacial climate with seas across the equator. Over the past few million years, perturbations from migrating giant planets in the system have caused Lyapunov's orbit to oscillate between increasingly eccentric orbits, in effect "preparing" native life for the cataclysm to come. About 500 years ago, a giant planet scattering event caused Lyapunov's orbit to be lowered by a few percent--enough that for the largely deserted planet it didn't produce a massive change to the climate, but enough that it was now orbiting in an unstable orbit around the system barycenter. It is thought that within 400 years, perturbations from the two suns will cause Lyapunov to become entirely uninhabitable.

There are several seas around the northern temperate region of Lyapunov. Rivers feed into them from all directions, but each type of river has different properties. The rivers leading in from the north are fueled by glaciers which melt during long periastrons, causing long, straight rivers. The rivers leading in from the south are more meandering and have many more tributaries since they collect the torrential rainfall near the equator that follows periastrons.

Lyapunov's seasons, if they can indeed be called such, are incredibly unpredictable due to the planet's chaotic and unstable orbit. As such, Lyapunov may freeze in a decades long winter, or it may spend several decades in an eccentric orbit which crosses between long mild winter and scorching short summer, or in a relatively constant circular orbit with constant summers and winters as the suns move beneath it.

During periods where summers come often, the equatorial lakes dry up except for the largest sea, as the evaporation rate is greatly increased. During this period, water is transported to the "temperate" regions by rainfall, while evaporation at the equator remains high, and water tends to be transferred to the temperate regions.

During periods with long winters, the temperate lakes and later the saltier seas begin to freeze, and snow covers up much of the temperate region. The lakes at the equator, then, become the only uncovered watermasses.

At this point in the planet's evolution, the glaciers at the North and South poles are permanent features, though during very hot summers their borders melt tremendously.

There is a region near the Base where the dirt is extremely soft for hundreds of kilometers. This overlaps the glacial region, producing an area of gorges with tall, though by no means structurally stable, walls. This soil also happens to be quite fertile.