Earth’s evolution of life largely depended on the formation of water, and the general consensus is that it appeared in liquid form about 4.6 billion years ago. However, a new study shows evidence of water molecules being in the Solar System and the planet itself some 135 million years earlier than recorded. Armed with this new information, astronomers think the evolution of life may also have roots millions of years sooner than believed, citing an October 30 National Geographic news report.
Adam Sarafian headed up a group with the Woods Hole Oceanographic Institution (WHOI) in Massachusetts. Together, they compiled enough data and evidence that supports their belief that the Earth’s oceans were already in place by millions of years before records reflect.
WHOI suggests that the inner solar system was still in its infancy when water formed. The earliest forms likely originated from space rocks — distant asteroids and comets from asteroid Vesta, some 225 million miles from Earth.
Previously, scientists thought that environmental conditions on the “hellish” planet were not optimal for water to form. Moreover, experts thought Earth formed as a dry body and water came many years later from constant foreign bombardments. Study co-author Horst Marschall weighed in.
“Some people have argued that any water molecules that were present as the planets were forming would have evaporated or been blown off into space. Surface water as it exists on our planet today must have come much, much later—hundreds of millions of years later.”
Researchers in search of water’s evolution and the origins of life-forms made comparisons of meteorites of known origin and those from Vesta, which evolved in the same region as Earth. That was some 14 million years before the Solar System’s formation. They concluded the composition of Vesta’s meteorites mirror Earth’s carbonaceous chondrites at their core, thus the source of water. Another co-author, Horst Marschall, explains.
“These primitive meteorites resemble the bulk solar system composition. They have quite a lot of water in them, and have been thought of before as candidates for the origin of Earth’s water. The study shows that Earth’s water most likely accreted at the same time as the rock. The planet formed as a wet planet with water on the surface.”
A major conclusion drawn from this new study is that while water occupying the Earth’s natural reservoirs today may have arrived at a later time, newly-acquired information suggests there were enough present millions of years earlier. As a consequence, life could have evolved much sooner.