Great balls of fire! Blazing meteorites from the outer regions of the solar system triggered life on Earth 4.6 billion years ago
Great balls of fire from the outer regions of the solar system brought the building blocks of life to Earth 4.6 billion years ago, a new study reveals.
Scientists at the Massachusetts Institute of Technology and Imperial College London found these ancient meteorites contained carbonaceous chondrite, which consisted of potassium and zinc.
Potassium helps produce a cell’s fluids, while zinc is vital in creating DNA.
The team found that these space rocks made up ten percent of the space rocks that smashed into the planet during its birth.
The other 90 percent came from the inner solar system’s non-carbonaceous (NC) material.
Life of Earth was triggered by fireballs that collided with the newly birthed planet 4.6 billion years ago
‘Our studies complement and confirm each other’s results in multiple ways,’ the study’s lead author Dr Nicole Nie told SWS.
‘Among moderately volatile elements, potassium is the least volatile while zinc is one of the most volatile elements.’
The meteorites provided 20 percent of Earth’s potassium and half its zinc.
Both are considered volatiles, which are elements or compounds that change from a solid or liquid state into vapor at relatively low temperatures.
Senior author Professor Mark Rehkämper, of Imperial College London’s Department of Earth Science and Engineering, said in a statement: ‘Our data show that about half of Earth’s zinc inventory was delivered by material from the outer Solar System, beyond the orbit of Jupiter.
‘Based on current models of early Solar System development, this was completely unexpected.’
Previous research suggested that the Earth formed almost exclusively from inner Solar System material, which researchers inferred was the predominant source of Earth’s volatile chemicals.
However, the new study provides the first evidence that Earth formed partly from carbonaceous meteorites from asteroids in the outer main belt.
‘This contribution of outer Solar System material played a vital role in establishing the Earth’s inventory of volatile chemicals,’ said Rehkämper.
‘It looks as though without the contribution of outer Solar System material, the Earth would have a much lower amount of volatiles than we know it today – making it drier and potentially unable to nourish and sustain life.’
The team analyzed 18 meteorites,11 from the inner region and the rest traveled from the outer areas.
The meteorites contained potassium and zinc and traveled from the outer regions of the solar system
And then, they measured the relative abundances of zinc’s five different forms – or isotopes.
They then compared each isotopic fingerprint with Earth samples to estimate how much these materials contributed to the Earth’s zinc inventory, showing that Earth only incorporated about ten percent of its mass from carbonaceous bodies.
The researchers found that material with a high concentration of zinc and other volatile constituents is also likely to be relatively abundant in water, giving clues about the origin of Earth’s water.