That one day on Venus is longer than an entire year on that planet is a claim that Snopes has seen repeatedly circulated in online forums, including Reddit and Quora, and on social media platforms like X, including the post below shared on Nov. 11, 2023.
At the time of this publication, the post had received more than 874,000 views:
Space fact:
One day on Venus is longer than one year on Venus. pic.twitter.com/rz6oZtWsd0
— World of Engineering (@engineers_feed) November 12, 2023
This claim is true.
A day on Venus is the equivalent in time as 243 Earth days. A year, on the other hand, equates to 225 days on Earth.
“That means that a day on Venus is a little longer than a year on Venus,” wrote NASA in an educational resource.
A day is defined as the time it takes a planet to make one full rotation on its axis which, on Earth, is 23 hours and 56 minutes. Meanwhile, a year is the time it takes a planet to orbit around the sun. On Earth, that takes approximately 365 days.
While Venus is slightly smaller in size than Earth, the yellow planet spins more slowly and in the opposite direction. This, in addition to its lineup in our solar system, lends to its exceptionally long days. According to the London-based observatory, Royal Museums Greenwich:
It takes Venus longer to rotate once on its axis than to complete one orbit of the Sun. That’s 243 Earth days to rotate once – the longest rotation of any planet in the Solar System – and only 224.7 Earth days to complete an orbit of the Sun.
A day on Venus is unlike a day on Earth, which sees one sunset and one sunrise roughly every 24 hours. On Venus, the sun rises every 117 Earth days – or just two times per Venus year.
Because Venus rotates in the opposite direction as Earth, the sun rises in the west and sets in the east. The small and rocky terrestrial planet is also described as being one of the hottest and most volcanically active planets in our solar system.