- A day of Venus lasts longer than a year
Obviously, by year we mean the year of Venus. Venus rotates on its axis once every 243 Earth days, while it orbits the sun once every 225 Earth days. Furthermore, its rotation is retrograde, and therefore opposite to that of Earth.
- There are probably donut-shaped planets in the universe.
Torus planets are a hypothetical possibility—and given the vastness of the universe, if something is possible, then it's also highly likely that one of these examples exists somewhere out there. If a planet had an extremely rapid rotation period, it would be able to create the appropriate shape by counteracting the gravitational force that would otherwise hold the celestial body together along the equator. Such rotations would cause space to open up along the poles, but would otherwise lead to a stable physical configuration.