A Venusian day is 243 Earth days long — longer than the planet’s entire 225-day year — and because Venus rotates backwards, the Sun would rise in the west and set in the east, though only once every 117 Earth days through its thick, cloud-choked sky.

A Venusian day is 243 Earth days long — longer than the planet’s entire 225-day year — and because Venus rotates backwards, the Sun would rise in the west and set in the east, though only once every 117 Earth days through its thick, cloud-choked sky.

Venus keeps the strangest clock and calendar in the solar system. It takes about 243 Earth days to turn once on its axis, and only about 225 Earth days to travel all the way around the Sun. On Venus, in other words, the day is longer than the year. The planet finishes a lap of the Sun before it has finished a single rotation. It gets stranger from there, and the figures are worth pulling apart, because two different “days” are hiding in this sto…