Some think that
meteorites brought indispensable materials for the beginning of life. A
meteorite discovered in Antarctica would give strength to the argument that
life on Earth may have started due to a boost from space, scientists say. The
analysis shows that the meteorite is rich in the gas ammonia. Contain the
element nitrogen, found in proteins and DNA that form the basis of the life as
we know.
Researchers say
meteorites as these may have come to Earth to supply the ingredients that were
necessary for life. Details of the study published by researchers at Arizona
State University and the University of California, Santa Cruz, are published in
the journal Proceedings of the National Academy of Sciences. The new study is
based on analysis of about 4 grams of powder extracted from a meteorite called
Grave Nunataks 95229, discovered in 1995. It showed that the powder contained
large amounts of ammonia, among other substances.
Nitrogen
Professor Sandra
Pizzarello, who led the research, said the study "shows that there are
asteroids out there that when fragmented and became meteorites, may have come
to Earth with an attractive mix of components, including a large amount of
ammonia." Meteorites like this could have supplied Earth enough nitrogen
in the right form to arise primitive forms of life, he says. Much of the
evidence shows that there was not much ammonia on the early Earth, so where do
they come?
Caroline Smith, Natural
History Museum of London
Previous studies have
focused on the meteorite "Murchison", who came to Australia in 1969
and which was found to be rich in organic compounds. The professor says that
some of the molecules found there correspond to later times in the history of
life. She believes that these compounds are too complex to have played a role
in life on Earth.
Asteroid Belt
The theory that the
planet was fertilized by a comet or asteroid arises partly from the belief that
the original Earth could not have offered a full inventory of simple molecules
needed for the process that led to primitive life. The suggestion is that the
asteroid belt between Mars and Jupiter, away from heat and pressure forming
planets, could have been a better place for that process.
Caroline Smith, a
meteorite expert at the Natural History Museum of London agrees that the
important factor in the new study is the nitrogen, but would like to see
similar results repeated in other meteorites. there are asteroids out there
that when fragmented and became meteorites, may have come to Earth with an
attractive mix of components, including a large amount of ammonia
Sandra Pizzarello
"One of the
problems with early biology on the early Earth is you need a lot of nitrogen
for all these processes occur prebiologicos and of course there nitrogen in
ammonia. "Much of the evidence shows that there was not much ammonia on
the early Earth, so where do they come?" He asks. Still do not know what
specifically what led to life on Earth began.
Pizzarello has
hypothesized that a meteorite material may have interacted with environments on
Earth such as volcanoes, but these are assumptions. "You find these
extraterrestrial materials (in meteorites) which have what you need," he
says, "but the how and the when, how and by what mechanism atmosphere
really do not know."
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