Hola amigos: A VUELO DE UN QUINDE EL BLOG., la Agencia Espacial NASA, nos informa que científicos planetarios han encontrado meteorítica evidencia de un reservorio de agua en Marte; Aunque la controversia aún rodea el origen, la abundancia y la historia del agua en Marte, este descubrimiento ayuda a resolver la cuestión de dónde la "falta de agua marciana" puede haber ido. Los científicos continúan estudiando registro histórico del planeta, tratando de entender el aparente cambio de un clima húmedo y cálido pronto para condiciones superficiales secas y frescas de hoy.
This illustration depicts Martian water reservoirs.
Recent research provides evidence for the existence of a third reservoir that is
intermediate in isotopic composition between the Red Planet’s mantle and its
current atmosphere. These results support the hypothesis that a buried
cryosphere accounts for a large part of the initial water budget of
Mars.
Esta ilustración muestra las reservas de agua en Marte. La investigación reciente ofrece evidencia de la existencia de un tercer depósito que es intermedio en la composición isotópica entre el manto del planeta rojo y su atmósfera actual. Estos resultados apoyan la hipótesis de que una enterrado cuentas criosfera para una gran parte del presupuesto inicial de agua de Marte.
Image Credit:
NASA
NASA
and an international team of planetary scientists have found evidence in
meteorites on Earth that indicates Mars has a distinct and global reservoir of
water or ice near its surface.
Though controversy still surrounds the origin, abundance and history of water
on Mars, this discovery helps resolve the question of where the “missing Martian
water” may have gone. Scientists continue to study the planet’s historical
record, trying to understand the apparent shift from an early wet and warm
climate to today’s dry and cool surface conditions.
The reservoir’s existence also may be a key to understanding climate history
and the potential for life on Mars. The team’s findings are reported in the
journal Earth and Planetary Science Letters.
“There have been hints of a third planetary water reservoir in previous
studies of Martian meteorites, but our new data require the existence of a water
or ice reservoir that also appears to have exchanged with a diverse set of
Martian samples,” said Tomohiro Usui of Tokyo Institute of Technology in Japan,
lead author of the paper and a former NASA/Lunar and Planetary Institute
postdoctoral fellow. “Until this study there was no direct evidence for this
surface reservoir or interaction of it with rocks that have landed on Earth from
the surface of Mars.”
Researchers from the Tokyo Institute of Technology, the Lunar and Planetary
Institute in Houston, the Carnegie Institution for Science in Washington and
NASA’s Astromaterials Research and Exploration Science Division, located at the
agency’s Johnson Space Center in Houston, studied three Martian meteorites.
The samples revealed water comprised of hydrogen atoms that have a ratio of
isotopes distinct from that found in water in the Red Planet’s mantle and
current atmosphere. Isotopes are atoms of the same element with differing
numbers of neutrons.
While recent orbiter missions have confirmed the presence of subsurface ice,
and melting ground-ice is believed to have formed some geomorphologic features
on Mars, this study used meteorites of different ages to show that significant
ground water-ice may have existed relatively intact over time.
Researchers emphasize that the distinct hydrogen isotopic signature of the
water reservoir must be of sufficient size that it has not reached isotopic
equilibrium with the atmosphere.
“The hydrogen isotopic composition of the current atmosphere could be fixed
by a quasi-steady-state process that involves rapid loss of hydrogen to space
and the sublimation from a widespread ice layer,” said coauthor John Jones, a
JSC experimental petrologist and member of NASA’s Mars Curiosity rover team.
Curiosity’s observations in a lakebed, in an area called Mount Sharp,
indicate Mars lost its water in a gradual process over a significant period of
time.
“In the absence of returned samples from Mars, this study emphasizes the
importance of finding more Martian meteorites and continuing to study the ones
we have with the ever-improving analytical techniques at our disposal,” said
co-author Conel Alexander, a cosmochemist at the Carnegie Institution for
Science.
In this investigation, scientists compared water, other volatile element
concentrations and hydrogen isotopic compositions of glasses within the
meteorites, which may have formed as the rocks erupted to the surface of Mars in
ancient volcanic activity or by impact events that hit the Martian surface,
knocking them off the planet.
“We examined two possibilities, that the signature for the newly identified
hydrogen reservoir either reflects near surface ice interbedded with sediment or
that it reflects hydrated rock near the top of the Martian crust,” said coauthor
and JSC cosmochemist Justin Simon. “Both are possible, but the fact that the
measurements with higher water concentrations appear uncorrelated with the
concentrations of some of the other measured volatile elements, in particular
chlorine, suggests the hydrogen reservoir likely existed as ice.”
The information being gathered about Mars from studies on Earth, and data
being returned from a fleet of robotic spacecraft and rovers on and around the
Red Planet, are paving the way for future human missions on a journey to Mars in
the 2030s.
These findings can be viewed online in their entirety at:
For more about the ARES Division at JSC, visit:
Learn about NASA’s Journey to Mars at:
NASA
Guillermo Gonzalo Sánchez Achutegui
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