The water could reach the Earth within billions of tons of carbonaceous chondrites, a type of meteorites, that fell about 3,800 million years ago, according to a research led by the Institute of Space Sciences (ICE-CSIC) and the Institut d'Estudis Espacials de Catalunya (IEEC).
The study, published by the journal Space Science Reviews and collected by the agency Efe, has discovered that carbonaceous chondrites incorporated hydrated minerals with organic matter from the protoplanetary disk prior to the formation of the planets.
The scientists who sign this study argue that these meteorites played "an important role in the enrichment in water of the primitive Earth ", since they would have facilitated the transport of volatile elements that accumulated in the outer regions of the so-called protoplanetary disk from which the planets formed more than 4,500 million years ago.
The Earth was formed in a much smaller environment close to the Sun, in relative absence of oxygen.
Carbonaceous chondrites come from bodies that, given their size generally less than a hundred kilometers, never melted or suffered internally chemical differentiation like planets.
Therefore, his study provides clues about the initial stages of aggregation of the first bodies that formed the planets.
The meteorites analyzed in this work belong to the Antarctic collection of NASA and to the fallen in Murchison (Australia) in 1969 and in Renazzo (Italy) in 1824.
«The chondrites constitute a fossil legacy of the creation of planetesimals, which provide information on the aggregation processes of the first formative blocks of the planets, but also of everything that happened inside him shortly after his training », explained the director of the study and researcher of the ICE-CSIC, Josep Maria Trigo.
According to Trigo, "there is a great debate about the origin of water on Earth and our study corroborates that carbonaceous chondrites were able to transport water very efficiently in their matrices."
"That water," he added, "seems to come from two types of objects formed at different distances from the Sun: hydrated asteroids and comets. Obviously, in order to know the origin of Earth's water we must study not only comets but also carbonaceous chondrites that come from a population of so-called transitional asteroids. "
The astrophysicist has pointed out that these meteorites "were much more numerous 4,000 million years ago but suffered a gravitational destabilization during the migration of Jupiter and Saturn to their current location".
"Those that did not end up being swallowed by Jupiter and Saturn were driven to the terrestrial planets and other regions of the Solar System, transporting water and organic matter accumulated in their interiors," according to the CSIC researcher. EFE