Why does Venus takes longer time to rotate about its own axis than to revolve around the sun?

Answer 1

Answer

The revolution period of Venus around its orbit (its "year") is 225 Earth days; however its rotational period around its own axis (its "day") is 243 Earth days! And unlike all other planets (except the tilted Uranus), its direction of rotation is opposite (or retrograde).

These two anomalies could be related; they might have been caused by a collision or by tidal forces due to Earth.

Answer 2

Its to do with Venus' orbit of the sun in that time, being of a similar length to its axial rotation period.

Venus takes 243 days to spin on its axis relative to the background stars, while it takes 224.7 days to orbit the sun. Although its spin on its axis is longer that its orbital period, an apparent day is 116.75 days, since it spins in the other direction to Earth and most other planets.

Answer 3

Because Venus's spin is retrograde, that is to say it spins "backwards". (Also it travels around the sun faster than it spins on its axis, meaning the Venusian "day" is longer than a Venusian "year".) That is the Venusian SIDEREAL day which is its rotation period.

The SOLAR day is how long the Sun takes to apparently travel once round the sky.

That's from one Venusian "noon" to the next.

The combination of retrograde spin and very slow spin causes the Solar day

to be much less than the time taken to spin once (the sidereal day).

On Earth the solar day is more than the sidereal day, but not by much.

Answer 4

When the planet originally formed, there was almost certainly a rate of rotation comparable to early Earth or Mars. However, some incident early in Venus's history altered its rotation, bringing it almost to a halt. The likely scenario is impact with a large asteroid or proto-planet, the collision almost totally counter-balancing its rotational momentum.

These types of collision were comparatively frequent in the early solar system. A similar massive collision is thought to have knocked loose a huge amount of crustal material from the Earth, which eventually formed the Moon.

Answer 5

A day on Venus is about 243 Earth days whereas a year on Venus is 224 Earth Days