Scientists discover new type of meteorite

The meteorite is believed to have broken off a 62mile long asteroid in the biggest solar system collision in the last three billion years

A rock that crashed to Earth around 470 million years ago has been identified as the first ever known meteorite of its kind.

The meteorite was discovered in a marine limestone quarry and is believed to have fallen to earth during one of the biggest space collisions in the last three billion years.

Scientists discovered the rock as part of a number of fragments which fell to earth and landed on the Swedish site.

It is believed to have broken off a massive 62-mile asteroid during a violent collision in the asteroid belt and is now helping to cast light on the beginnings of our solar system.

The meteorite, measuring around four inches in length, has been named Ost 65, after a nearby church named Osterplanaand.

Stone cutters have plucked 101 fossil meteorites from the pit’s ancient pink limestone in the last two decades, all found to be the most common types of meteorites, called L chondrites, which hit the planet around the same time.

The limestone quarry preserves the remnants of the cosmic cataclysm that took place 470 million years ago, during the Ordovician Period.

Scientists think there was an enormous crash between two large bodies out in the asteroid belt.

The crash blew apart two asteroids, or an asteroid and comet, slinging dust and debris toward Earth.

One of the impactors was the source of all L-chondrite meteorites.

But no one has ever found a piece of the rock that hit the L-chondrite parent, until now.

This single remnant is of a kind not known among the 50,000 documented meteorites that have fallen on Earth in recent times.

Researchers used state of the art chemical analyses to classify the meteorite and show it is distinct from all known meteorites that have fallen to Earth to date.

Using a dating technique known as cosmic-ray exposure, they also found the meteorite’s age is within a million years of the L chondrite collision.

This suggests the meteorite, described in the journal Nature Communications, represents the remains of the asteroid which was responsible for the break up of the massive L chondrite space rock.

The asteroid may have largely been destroyed during the collision, a possible explanation for why this type of meteorite has not previously been recovered on Earth.

But the possibility remains its remnants could still be out in space along with the L chondrites that regularly fall to Earth.

Professor Birger Schmitz, a nuclear physicist at Lund University, Sweden, said: “The cosmic ray exposure age of Ost 65 shows it may be a fragment of the impactor that broke up the L-chondrite parent body.

“This may be the first documented example of an”extinct’ meteorite, that is, a meteorite type that does not fall on Earth today because its parent body has been consumed by collisions.

“The meteorites found on Earth today apparently do not give a full representation of the kind of bodies in the asteroid belt around 500 million years ago.”

Prof Schmitz added: “The Ost 65 meteorite is significant because it demonstrates that 500 million years ago we may have had different meteorites falling to Earth than what we see today.

“Some may be extinct, whereas others, such as the L chondrites, still fall on Earth.

“Apparently there is potential to reconstruct important aspects of solar system history by looking down in Earth’s sediments, in addition to looking up at the skies.”