Hola amigos: A VUELO DE UN QUINDE EL BLOG., la Agencia Espacial NASA, va estudiar el origen del "Océano de las Tormentas" (Oceanus Procellarum) en la Luna, cuyo diámetro es de 3,000 kilómetros; con su misión: NASA's Gravity Recovery and Interior Laboratory (GRAIL) misión, esta investigación determinará si el origen fue: un impacto de un meteorito o algo parecido como un asteroide, cuyo cráter es una incógnita para la ciencia espacial.
Earth's moon as observed in visible light (left),
topography (center, where red is high and blue is low), and the GRAIL gravity
gradients (right). The Procellarum region is a broad region of low topography
covered in dark mare basalt. The gravity gradients reveal a giant rectangular
pattern of structures surrounding the region.
Image Credit:
NASA/GSFC/JPL/Colorado School of
Mines/MIT
This artist's concept combines gravity gradients
from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission, an image
mosaic from the Lunar Reconnaissance Orbiter's (LRO) Wide Angle Camera, and
topography data from LRO's Lunar Orbiter Laser Altimeter.
Image Credit:
NASA/Colorado School of Mines/MIT/JPL/GSFC
Feature Link:
Using data from NASA’s Gravity Recovery and Interior Laboratory (GRAIL),
mission scientists have solved a lunar mystery almost as old as the moon
itself.
Early theories suggested the craggy outline of a region of the moon’s surface
known as Oceanus Procellarum, or the Ocean of Storms, was caused by an asteroid
impact. If this theory had been correct, the basin it formed would be the
largest asteroid impact basin on the moon. However, mission scientists studying
GRAIL data believe they have found evidence the craggy outline of this
rectangular region -- roughly 1,600 miles (2,600 kilometers) across -- is
actually the result of the formation of ancient rift valleys.
"The nearside of the moon has been studied for centuries, and yet continues
to offer up surprises for scientists with the right tools," said Maria Zuber,
principal investigator of NASA's GRAIL mission, from the Massachusetts Institute
of Technology, Cambridge. "We interpret the gravity anomalies discovered by
GRAIL as part of the lunar magma plumbing system -- the conduits that fed lava
to the surface during ancient volcanic eruptions."
The surface of the moon’s nearside is dominated by a unique area called the
Procellarum region, characterized by low elevations, unique composition, and
numerous ancient volcanic plains.
The rifts are buried beneath dark volcanic plains on the nearside of the moon
and have been detected only in the gravity data provided by GRAIL. The
lava-flooded rift valleys are unlike anything found anywhere else on the moon
and may at one time have resembled rift zones on Earth, Mars and Venus. The
findings are published online in the journal Nature.
Another theory arising from recent data analysis suggests this region formed
as a result of churning deep in the interior of the moon that led to a high
concentration of heat-producing radioactive elements in the crust and mantle of
this region. Scientists studied the gradients in gravity data from GRAIL, which
revealed a rectangular shape in resulting gravitational anomalies.
"The rectangular pattern of gravity anomalies was completely unexpected,"
said Jeff Andrews-Hanna, a GRAIL co-investigator at the Colorado School of Mines
in Golden, Colorado, and lead author of the paper. "Using the gradients in the
gravity data to reveal the rectangular pattern of anomalies, we can now clearly
and completely see structures that were only hinted at by surface
observations."
The rectangular pattern, with its angular corners and straight sides,
contradicts the theory that Procellarum is an ancient impact basin, since such
an impact would create a circular basin. Instead, the new research suggests
processes beneath the moon’s surface dominated the evolution of this region.
Over time, the region would cool and contract, pulling away from its
surroundings and creating fractures similar to the cracks that form in mud as it
dries out, but on a much larger scale.
The study also noted a surprising similarity between the rectangular pattern
of structures on the moon, and those surrounding the south polar region of
Saturn’s icy moon Enceladus. Both patterns appear to be related to volcanic and
tectonic processes operating on their respective worlds.
"Our gravity data are opening up a new chapter of lunar history, during which
the moon was a more dynamic place than suggested by the cratered landscape that
is visible to the naked eye," said Andrews-Hanna. "More work is needed to
understand the cause of this newfound pattern of gravity anomalies, and the
implications for the history of the moon."
Launched as GRAIL A and GRAIL B in September 2011, the probes, renamed Ebb
and Flow, operated in a nearly circular orbit near the poles of the moon at an
altitude of about 34 miles (55 kilometers) until their mission ended in December
2012. The distance between the twin probes changed slightly as they flew over
areas of greater and lesser gravity caused by visible features, such as
mountains and craters, and by masses hidden beneath the lunar surface.
The twin spacecraft flew in a nearly circular orbit until the end of the
mission on Dec. 17, 2012, when the probes intentionally were sent into the
moon’s surface. NASA later named the impact site in honor of late astronaut
Sally K. Ride, who was America's first woman in space and a member of the GRAIL
mission team.
GRAIL’s prime and extended science missions generated the highest resolution
gravity field map of any celestial body. The map will provide a better
understanding of how Earth and other rocky planets in the solar system formed
and evolved.
The GRAIL mission was managed by NASA’s Jet Propulsion Laboratory (JPL) in
Pasadena, California, for NASA's Science Mission Directorate in Washington. The
mission was part of the Discovery Program managed at NASA's Marshall Space
Flight Center in Huntsville, Alabama. GRAIL was built by Lockheed Martin Space
Systems in Denver.
For more information about GRAIL, visit:
NASA
Guillermo Gonzalo Sánchez Achutegui
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