Supercomputer simulations provide new theory about Moon's creation

Many of the previous theories surrounding the Moon's formation suggest that it slowly coalesced from this soup of orbital debris until finally, the remainder of the material not accumulated by the satellite fell back in towards Earth.

In this scenario, the orbital debris would have been largely comprised of the remains of Theia. However, rock samples recovered from the Moon’s surface by Apollo-era astronauts showed a surprising structural and isotopic similarity to those found on Earth, IGN entertainment news website reports.

Whilst it is possible, the authors of a new study found it unlikely that the material from Theia would have such a close match with that of the Earth.

In the new study, a team of researchers from Durham University in the UK used the powerful DiRAC supercomputing facility to run a range of simulations that could account for the creation of Earth’s moon.

The supercomputer used a significantly larger number of particles to simulate the ancient collision compared to previous studies. According to the team, lower-resolution simulations can omit important aspects of the collision process.

Over the course of the study, the scientists ran hundreds of these high-resolution simulations while varying a range of key parameters, including the masses, spins, angles, and speeds of the two unfortunate worlds.

The simulations revealed that a large body with a Moon-like mass and iron content could have coalesced almost immediately in orbit following the Earth-Theia collision. The detailed simulation showed that the newly born hypothetical satellite would have been created beyond the Roche limit - which is the orbital distance at which a satellite can orbit a planet without being shredded by its gravity.

Furthermore, the outer layers of such a world would be rich in material ejected from Earth, thus explaining the similarities between the Apollo-era rocks and those from our planet.