Karisia has 1.43 times Earth radius, 2.62 times the mass and 0.9 times Earth density. As such, it has 1.29G at the surface.
Karisia's period is 8 hours. It has an axial tilt of currently around 24.99°, though this varies due to the lack of a large moon.
Karisia's surface is 60% water and 2% ice. The temperature average is 24°C, varying from -69° to 46°.
Karisia's atmosphere is 73.7% nitrogen, 21.6% oxygen, 4.1% argon, 0.6% carbon dioxide, and trace other gases.
Karisia is most notable for being the Iridi homeworld. It is very ecologically diverse, animals having to adapt to the rapid day/night cycles.
There is one city on Karisia, with a population of 100 million. It is around halfway between the equator and the north pole.
An enormous area around that is hydroponics and protein farms, as well as spaceports (from which Iridi Spaceships launch) and power plants (mainly fusion).
There are also twelve space stations in high orbit, and many satellites.