Venus takes about 243 Earth days to turn once on its axis, and about 225 Earth days to travel once around the Sun.
Which means a Venusian day is longer than a Venusian year.
It gets stranger. Venus rotates backwards — retrograde, opposite to almost every other planet in the solar system. If you could see the sky through its clouds, the Sun would rise in the west and set in the east.
Because the spin and the orbit interact, the interval between one sunrise and the next works out at roughly 117 Earth days. You would get just under two sunrises in a Venusian year.
Nobody is certain why it turns this way. The leading explanations involve either an enormous early collision that flipped the planet, or the dense atmosphere and solar tides gradually torquing the rotation over billions of years.
And the atmosphere is dense. Surface pressure is about 92 times Earth’s — comparable to being 900 metres underwater — and the surface sits around 460°C, hot enough to melt lead, hotter than Mercury despite being further from the Sun.
Venus is almost exactly Earth’s size. It is the clearest reminder available that similar starting conditions guarantee nothing at all.
