When it comes to planetary dynamics, Uranus was the nerd among all the worlds that sit in our solar system. The ice giant is exposed to temperatures far lower than those of Neptune, which sits farther out in the neighborhood and is tilted sideways – a weird feature that puzzles scientists around the world.
Over the years, astronomers observing Uranus poles are not aligned with the sun while the planet is spinning on its side. The feature made the planet distinctly different from its planetary siblings, but the reason for this bias was only a secret until an international team, led by scientists from the University of Durham, UK, came to the rescue. 
As it is very unlikely is that Uranus originated in this way, various scenarios have been proposed to explain the inclination. The most supported theory was that of a massive collision in which a celestial body shattered the planet sideways. However, such an interaction is said to relieve the atmosphere of the planet, which is still present in this particular case.
"Uranus turns on its side with its axis almost perpendicular to all other planets in the solar system," said Jacob Kegerreis, the lead author of the recent work, in a statement. "This was almost certainly caused by a huge impact, but we know very little about how it actually happened and how otherwise such a violent event affected the planet."
For this reason, Kegerreis and his team ran into this collision to a series of high-resolution simulations. They explored as many as 50 shattering scenarios to determine which would best explain the slope and freezing conditions currently prevailing on the planet.
The results of the work revealed about four billion years ago, when the solar system went through the chaos phase and planetary bodies still sat down, a protoplanet – a world in the process of creation – of ice and rock could have Uranus tripped ,
According to the simulations, the protoplanet would have been twice as large as our Earth, meaning that the interaction was probably strong enough to beat Uranus (14 times larger than the Earth) sideways, but not enough to keep the planet's atmosphere to strike.
The fierce collision, as suggested by the simulations, affected the development of Uranus billions of years ago and shaped the planet into what it is today. In essence, the team found that debris from the impacting planet formed a thin shell near the edge of the Uranus ice sheet. This shell could, the researchers have included heat from the core and have contributed to cooling temperatures on the planet.
This collision even explains the formation of inner uranium moons. During the simulation, the team found that the interaction between the protoplanete and Uranus had thrown rocks and ice into the planet's orbit. This material later fused and produced the moons.
The study titled "Consequences of Huge Impact on Early Uranus for Rotation, Internal Structure, Debris and Atmospheric Erosion" was published on July 2 in the Astrophysical Journal.