A work of a group of scientists from the Carnegie Institution, the United States has found that much of the water in our solar system probably originated from the ice that formed in interstellar space.
Water in the Solar System, not only on Earth but also in comets and icy moons and gloomy basins on Mercury. It has even been found in samples of mineral water in meteorites, the Moon and Mars. In particular, comets and asteroids, being primitive objects provide a “time capsule” natural conditions during the early days of our solar system. Her ice can give scientists clues on the ice that surrounded the Sun after birth, whose origin was an open question until now.
In his youth, the sun was surrounded by a protoplanetary disk, called solar nebula from which the planets were born. However, it was unclear if the ice in this album originated in the interstellar cloud of the Sun itself, or if the water was removed and re-created by the chemical reactions taking place in the solar nebula.
“If the water in the early Solar System was came mainly in the form of ice from interstellar space, then it is likely that ice like, along with the prebiotic organic matter they contain, are abundant in most or all of the protoplanetary disks around of the stars, “explains Conel Alexander, the lead author of the study published in Science.
“But if the water in the early solar system was largely the result of local chemical processes during the birth of the sun, then it is possible that the abundance of water varies considerably in the formation of planetary systems, obviously has implications for the possibility of the emergence of life in other places. “
In studying the history of the ice in our solar system, the team, led by Ilsedore Cleeves, University of Michigan, focused on hydrogen and its heavier isotope deuterium. Isotopes are atoms of the same element have the same number of protons but different numbers of neutrons.
The mass difference between isotopes results in subtle differences in behavior during chemical reactions. Consequently, the ratio of hydrogen and deuterium in the water molecules can inform scientists on the conditions under which the molecules are formed.
For example, interstellar ice water has a high proportion of deuterium and hydrogen, due to the very low temperatures at which it is formed, but until now it was not known how much of this enrichment of deuterium was removed by chemical processes during the birth of the sun or the amount of water rich ice deuterium the newborn solar system was able to produce itself.
DISK MODELS protoplanetary
The team created models that simulate a protoplanetary disk in which all deuterium ice space has been removed by chemical processing and the system has to re-start “from scratch” in ice production with deuterium over a period of millions of years.
They did so in order to see if the system can reach the proportions of deuterium and hydrogen found in meteorite samples, ocean water on Earth and comets and saw that it was not, demonstrating that the least part of the water from our own Solar System originated in interstellar space and predates sunlight.
“Our results show that a significant fraction of water in our solar system, the key ingredient for the promotion of life, is older than the Sun, indicating that there was abundant interstellar ices rich in organic matter in all young planetary systems. “
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