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4 months ago
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It is well known that the reign of the dinosaurs came to an end when a giant asteroid smashed into Earth 66 million years ago.
But until now, the origin of this space rock has remained unclear.
Now, experts from the University of Cologne claim that the six-mile-wide asteroid travelled millions of miles from beyond Jupiter before smashing into our planet.
'The fate of the dinosaurs and many other species was sealed by this projectile from the outer reaches of the solar system,' said Professor Dr Carsten Münker.
The discovery will inevitably raise questions about whether another devastating asteroid could be headed our way.
It is well known that the reign of the dinosaurs came to an end when a giant asteroid smashed into Earth 66 million years ago. But until now, the origin of this space rock has remained unclear (artist's impression_
Artistic reconstruction of the historic event, known as Chicxulub, with lethal impact spherules raining down from the sky 66 million years ago
Dr Mario Fischer-Gödde and his colleagues say the killer rock was a huge carbonaceous chondrite (C-type) asteroid, a carbon-rich type that is common in the solar system but rarely impacts Earth.
C-type asteroids formed beyond Jupiter around 4.6 billion years ago when the solar system was born.
Dr Fischer-Gödde told MailOnline: 'C-type asteroids represent leftover building blocks of the outer solar system gas and ice planets.
'Owing to the dynamic evolution of the solar system, with Jupiter's early migration, the orbits of asteroids got disturbed and they were scattered towards the inner solar system where they are found today – in the asteroid belt.'
The first four planets (Mercury, Venus, Earth and Mars) form the inner solar system, while the last four (Jupiter, Saturn, Neptune and Uranus) make up the outer solar system. The dividing gap between the inner and outer solar system was bigger than it is today, experts report. Planet Nine is a hypothetical planet that may have existed, other studies say
Jupiter is the fifth planet from the Sun, and the largest in the solar system - more than twice as massive as the other planets combined
It's already well known that the dinosaurs were wiped out by the Chicxulub impact event – a plummeting asteroid that slammed into a shallow sea in what is today the Yucatán peninsula in Mexico around 66 million years ago.
For those creatures not killed directly by the impact, the collision released a huge dust and soot cloud that partially blocked out the sun and caused temperatures to plummet.
As a result, 75 per cent of all animal and plant species were wiped out.
All non-avian dinosaurs, pterosaurs, ammonites and most marine reptiles disappeared, whilst birds, crocodiles, and turtles survived, as well as some mammals – from which humans evolved.
Today, the event is marked by a thin layer of sediment called the K-Pg boundary, which can be found throughout the world in marine and terrestrial rocks.
Today, the event is marked by a thin layer of sediment called the K-Pg boundary, which can be found throughout the world in marine and terrestrial rocks, dated to 66 million years ago (pictured here in Zumaia, Spain)
The Chicxulub asteroid slammed into a shallow sea in what is now the Gulf of Mexico around 66 million years ago
What are carbonaceous chondrites?
Carbonaceous chondrites are rocky objects that make up around 75% of all known asteroids in the solar system - more than any other type.
C-types are darker than other asteroids due to the presence of carbon and are some of the most ancient objects in the solar system - dating back to its birth about 4.6 billion years ago.
According to experts, volatile-rich C-types have been relatively untouched since they were formed billions of years ago.
However they rarely reach Earth; less than than 5 per cent of meteorites that fall to Earth are carbonaceous chondrites.
Dated to 66 million years ago, the rocky boundary shows unusually high levels of 'platinum-group metals' such as iridium and ruthenium, which are rare on Earth but common in asteroids.
From this, scientists determined that Earth was hit by a huge rocky object that covered it with debris – but the origin of the object has been poorly understood.
To learn more, the German team analysed rocky samples taken from the K-Pg boundary – specifically looking for traces of ruthenium in them.
For comparison, they also analysed samples from other rocks, including from other asteroid impacts and two carbonaceous chondrites.
According to the results, ruthenium traces in the K-Pg boundary rocks and the carbonaceous chondrites were the same.
This shows that the Chicxulub impactor likely came from a C-type asteroid that formed in the outer solar system.
They also rule out a comet as the impactor, as other theories had suggested.
Simply put, comets are made of ice and rock, while asteroids are made of rock and metal.
While C-type asteroids are associated with the outer solar system, 'S-type' asteroids are much more common in the inner solar system.
S-type (stony) asteroids are made of silicate materials as well as nickel-iron and are the most common visitors to the Earth of the asteroid types.
The researchers say that within the last 500 million years, almost exclusively fragments of S-type asteroids have hit the Earth.
Well over 80 percent of all asteroid fragments that hit the Earth in the form of meteorites come from the inner solar system.
Professor Dr Carsten Münker, co-author of the study, added: 'We found that the impact of an asteroid like the one at Chicxulub is a very rare and unique event in geological time.'
The new study has been published in the journal Science.
KILLING OFF THE DINOSAURS: HOW A CITY-SIZED ASTEROID WIPED OUT 75 PER CENT OF ALL ANIMAL AND PLANT SPECIES
Around 66 million years ago non-avian dinosaurs were wiped out and more than half the world's species were obliterated.
This mass extinction paved the way for the rise of mammals and the appearance of humans.
The Chicxulub asteroid is often cited as a potential cause of the Cretaceous-Paleogene extinction event.
The asteroid slammed into a shallow sea in what is now the Gulf of Mexico.
The collision released a huge dust and soot cloud that triggered global climate change, wiping out 75 per cent of all animal and plant species.
Researchers claim that the soot necessary for such a global catastrophe could only have come from a direct impact on rocks in shallow water around Mexico, which are especially rich in hydrocarbons.
Within 10 hours of the impact, a massive tsunami waved ripped through the Gulf coast, experts believe.
Around 66 million years ago non-avian dinosaurs were wiped out and more than half the world's species were obliterated. The Chicxulub asteroid is often cited as a potential cause of the Cretaceous-Paleogene extinction event (stock image)
This caused earthquakes and landslides in areas as far as Argentina.
While investigating the event researchers found small particles of rock and other debris that was shot into the air when the asteroid crashed.
Called spherules, these small particles covered the planet with a thick layer of soot.
Experts explain that losing the light from the sun caused a complete collapse in the aquatic system.
This is because the phytoplankton base of almost all aquatic food chains would have been eliminated.
It's believed that the more than 180 million years of evolution that brought the world to the Cretaceous point was destroyed in less than the lifetime of a Tyrannosaurus rex, which is about 20 to 30 years.
