Science
Asteroids found in the inner Solar System could be the source of most of Earth's water, recent research has shown, contradicting other suggestions that water was brought to Earth from the outer part of the system by comets.
Scientists previously believed that water was brought to Earth by comets that flew into our solar system, collided with other objects somewhere outside Jupiter's orbit, and then headed closer to To the sun.
“The results of our research have shown important new data on the origin of volatile substances within the solar system, including substances from the Earth,” said research leader Konel Alexander ( Conel Alexander) from the Carnegie Institution in Washington.
These data have made it possible to compile new models of the formation and orbital evolution of planets and smaller objects in our solar system, he added.
During the research, scientists analyzed samples of carbon-rich chondrites. These primitive meteorites are believed to be key sources of Earth's first volatile substances, such as hydrogen and nitrogen.
The team of scientists studied different isotopes of hydrogen, nitrogen and carbon in chondrite samples. Isotopes are versions of chemical elements that have different numbers of neutrons in the atomic nucleus. For example, the deuterium isotope, also known as heavy hydrogen, contains 1 neutron, while ordinary hydrogen does not have a single neutron in its core.
The amount of deuterium in the frozen water of space objects sheds light on where these objects were formed within the solar system at the very beginning of its appearance. In total, bodies that formed farther from the Sun have a relatively high concentration of deuterium.
After analyzing 86 samples of chondrites for deuterium content, the researchers assumed that the parent bodies of these meteorites formed relatively close to the Sun, possibly within the main asteroid belts between Mars and Jupiter.
Unlike meteorites, comets have a much higher concentration of deuterium. As a result, scientists believe that most of them formed outside the solar system. The isotopic composition of most of our planet is comparable to chondrites, not comets. It is likely that water and other volatile substances were brought to Earth by the parent asteroids of these chondrites.