The Chelyabinsk Meteorite May Have Been Involved in The Smash That Formed Our Moon

A meteorite that exploded in the sky over Chelyabinsk, Russia could have been involved in the giant impact that formed the Moon.

A new way of dating rocks in space using analysis of minerals within meteorites has yielded a promising finding. The technique could give us a new look at the violent early history of the Solar System, and how it evolved into its current shape.

The impact ages of meteorites are often controversial, according to a scientist at the University of Cambridge.

Our work shows that we need to draw on multiple lines of evidence to be more certain about impact histories.

Around 4.5 billion years ago, asteroids and meteorites were part of the formation of the Solar System. The planets formed when the Solar System was formed from a disk of dust and gas around the Sun.

The history on Earth and other planets is difficult to trace due to geological and weather processes. Large surface impacts can be hidden.

Asteroids can fall down to the planet as a meteorite if they get sucked into Earth's gravity well.

The minerals found in meteorites can be dated. There is a method of dating in zircon crystals. When it is forming, zircon has elements of both uranium and lead. Any lead found in zircon has to be the result of radioactive decay. We know the age of the zircon from how long it takes to decay.

An impact can affect the radioisotope mineral ages. The Chelyabinsk meteorite had undergone two impact events, one 4.5 billion years ago and the other 50 million years ago, with this tool in hand.

The way the meteorite shattered over successive impacts was studied by Walton and his colleagues.

The shock events experienced by the meteorites on their parent bodies can be dated using thephosphates in most primitive meteorites.

The researchers studied the details of how the minerals had shattered and the effect of impact-induced heating on the crystal structure.

They found that the earlier impact shattered the minerals into small pieces and subjected them to high temperatures. The impact seemed less severe with lower pressures and temperatures. The impact is thought to have occurred less than 50 million years ago.

They believe the impact that broke the meteorite off its larger parent body sent it on a collision course with Earth.

There was a lot of high-energy rock-smashing in space between 4.48 to 4.44 billion years ago, according to the findings about the earlier impact. This time frame is important because it could coincide with two major formative periods in Solar System history: the migration of the giant planets, or the ancient collision that scientists believe broke off a chunk of baby Earth to form the Moon.

The fact that all of these asteroids record intense melting at this time might indicate Solar System reorganization, either resulting from the Earth-Moon formation or perhaps the orbital movements of giant planets.

The giant planets form farther from the Sun than their current positions, and move closer in over time. This motion would have caused a lot of damage to the Solar System.

In the Moon formation scenario, a Mars-sized body is thought to have smashed into Earth around 4.5 billion years ago and ejected a bunch of material into space, which coalesced to form the Moon. There would be an increase in crashes because of this spray of ejecta.

The next step in the research is to revisit the timing of the Moon's formation, which should shed more light on this fascinating mystery.

The research has been published.