Venus is the only planet to spin clockwise!

In many ways, you can say that Venus is Earth’s twin. How? Well, it has a similar size, mass, density and chemical composition. But then what makes Earth liveable but not Venus? Venus has a high temperature and extreme pressure and both these conditions make it difficult for life to survive on this planet.  

While this is known forever, there is one mystery about our closest neighbour that's been unexplained for decades. Any guess what it is? It spins in a different direction from the other planets around the sun. Yes, Venus, the second planet in the solar system, spins on its axis clock-wise from east to west, while all other planets barring Uranus (which rotates on its side since its axis is tilted), spin anti-clockwise from west to east. But scientists still haven't figured out why.  

Why does it spin the wrong way?  
The direction the planets rotate is the same direction the sun rotates, and the sun rotates anti-clockwise. But then why does Venus spin clockwise? Though, scientists do not have any conclusive answers but there are many theories.  

Planetary Collision: One of the most popular theories is that after it formed, Venus probably rotated anti-clockwise like all the other planets. But at some point it was struck by a massive object (perhaps another planet) that sent it spinning in a different direction or reversed its rotation. 

Furthermore, this would also explain why Venus rotates so slowly. For example, it takes Venus 243 Earth days to complete one rotation about its axis. That is exceptionally long compared to Earth’s 24-hour rotation. A collision with another planet could have slowed down the rotation of Venus.  

Other explanations: Another theory holds that Venus initially spun in the same direction as most other planets and, in a way, still does: it simply flipped its axis 180 degrees at some point. In other words, it spins in the same direction it always has, just upside down, so that looking at it from other planets makes the spin seem backward.  

Now you would ask what could have turned it upside down? Scientists say that the sun's gravitational pull on the planet's very dense atmosphere could have caused strong atmospheric tides. Such tides, combined with friction between Venus's mantle and core, could have caused this flip.  

Venus facts  
Some other facts about Venus that you would be surprised to know are:  

• A day on Venus is much longer than one on Earth. A day there lasts a little more than 243 Earth-days, actually making it longer than a Venusian year, which is only about 224 Earth-days long.   
• Venus is named after the ancient Roman goddess of love and beauty, Aphrodite.  
• Venus is the hottest planet in our solar system.  
• As the brightest natural object in Earth's night sky after the Moon, Venus can cast shadows and can be visible to the naked eye in broad daylight.