Venus is the second planet from the sun, the first being Mercury and the third one Earth. It is similar to our planet in size and density. That’s why it is often considered to be the Earth’s little sister.

Venus turns around the sun in 225 days and around itself in 243 days. The combination of these two rotations means that its solar day does not last 24 hours like on Earth, but extends over 117 days (terrestrial). Each region of the planet is lit by the sun for almost two months (terrestrial) before slipping into darkness (nocturnal side) for another 2 months (terrestrial).

Venus’ rotation on itself has another characteristic that distinguishes it from our planet: it is retrograde. Therefore, on Venus, if the sun were able to shine through the thick clouds that surround it, it would rise in the west, while on Earth, like on the majority of planets, it rises in the east.

Therefore, in relation to the sun, Venus’ rotation is retrograde. But the rotation of its atmosphere in relation to its surface is also retrograde: up until about 90 kilometres in altitude, the atmosphere turns in the opposite direction to the surface. Beyond 90 kilometres, the speed changes and becomes relatively fixed in local time: the atmosphere does not turn with the planet.