How Long Is A Day On Venus (And Why)?

Exact Answer: 116.75 Earth Days

Venus is the second planet from Earth. It is considered the second most bright natural object in the Earth’s sky after the moon. Venus is a terrestrial planet and is also known as earth’s sister planet. Venus was known to be a habitable planet for humans until the 1960s when scientists found Venus to be unfit for life on Venus. The reason behind that was the extreme temperatures and atmospheric pressure on Venus. 

How Long Is A Day On Venus?

When answering the question about how long is a day on Venus, then it is said that one day on Venus is equal to 116.75 Earth Days. However, there could be variations in answers while answering this question.

The time for how long is the day on Venus depends on how the concerned person perceives the meaning of the day to be. By the term ‘day’, one can mean it to be a sidereal day or a solar day. Although, both of these terms define the word day only, both of them have a different meaning based on calculation factors of counting a single day to be.

A sidereal day means the exact time in which the planet completes one rotation in its rotational axis. Talking about Earth, it takes exactly 23 hours 56 minutes, and 4.1 seconds for one sidereal day to get completed.

Moreover, talking about the solar day, it means the time duration which takes the Sun to reach the same position in the sky when seen from the surface of the respective planet. On Earth, one solar day is equal to exactly 24 hours. In general, the solar day only is considered as the calculative method to know how long a day is. That is the reason why it is said that one day on Earth is equal to 24 hours.

One sidereal day on Venus is equal to 243.025 Earth days. That is almost equal to a complete year on earth.

Whereas, one solar day on Venus is equal to 116.75 Earth Days. Thus, when asked about how long a day is on Venus, the time duration of completion of one solar day on Venus is answered as the answer.

Here is a quick summary of how long is a day on Venus, depending upon the two different theories of calculating the length of the day:

Why Is A Day On Venus That Long?

Sidereal day and solar day are both used to define a day, however, they both can vary when used to calculate the day. 

As the Sidereal day on Venus is 243.025 Earth days. That means, it takes Venus 243.025 Earth Days to complete just one rotation on its axis. Interestingly, this is the longest duration for which a planet completes a rotation. 

However, there are more theories to this question of how long a day on Venus is which tells that a single day on Venus lasts longer than a complete year on Earth. These theories are based on the fact that Venus has a retrograde rotation method. That means, if an individual views the Venus planet from above its Northern pole region, then it will seek to rotate in a clockwise rotation along its axis. Whereas, it seems in a counter-clockwise direction around the Sun.

Moreover, if you live on the surface of Venus, then the Sun would rise in the west and set in the East. Completely contradictory to what happens on Earth.

Whereas, it takes the Sun 116.75 Earth Days to reach the same position when seen from the surface of Venus. This is the exact answer to how long a day is on Venus.

Conclusion

Almost each planet in the solar system rotates in an anticlockwise direction when viewed from the north pole region of the Earth. Whereas Venus is the only planet that rotates clockwise in the retrograde direction, making Venus takes the longest time to complete one rotation, that is, 243.025 days. Moreover, talking about solar day length, then it is equal to 116.75 Earth days.

References

1. https://books.google.com/books?hl=en&lr=&id=1IOvXF–bqsC&oi=fnd&pg=PP11&dq=venus&ots=y5yvsv-Vsz&sig=qMy7yvmU6xL6sErHJX9lBBvQViI
2. https://www.jstor.org/stable/1706530