Hola amigos: A VUELO DE UN QUINDE EL BLOG., la Agencia Espacial NASA, nos informa mediante el gráfico que....zona denominada Maskelyne es uno de los muchos depósitos volcánicos jóvenes recién descubiertas en la Luna. Llamados Parches irregulares, se cree que estas áreas para ser restos de pequeñas erupciones basálticas que ocurrieron mucho antes de que finalice comúnmente aceptada de vulcanismo lunar, entre 1 y 1,5 mil millones años.
NASA’s Lunar Reconnaissance Orbiter (LRO), ha proporcionado a los investigadores una fuerte evidencia de la actividad volcánica de la Luna se redujo gradualmente en lugar de detenerse abruptamente hace mil millones de años.............................
Decenas de depósitos de roca distintivas observadas por LRO se estima en menos de 100 millones de años. Este período de tiempo corresponde al período Cretácico de la Tierra, el apogeo de los dinosaurios. Algunas áreas pueden ser menos de 50 millones de años. Los detalles del estudio se publican en línea en la edición del domingo de Nature Geoscience........................
The feature called
Maskelyne is one of many newly discovered young volcanic deposits on the Moon.
Called irregular mare patches, these areas are thought to be remnants of small
basaltic eruptions that occurred much later than the commonly accepted end of
lunar volcanism, 1 to 1.5 billion years ago.
Image Credit:
NASA/GSFC/Arizona State
University
NASA’s Lunar Reconnaissance Orbiter (LRO) has provided researchers strong
evidence the moon’s volcanic activity slowed gradually instead of stopping
abruptly a billion years ago.
Scores of distinctive rock deposits observed by LRO are estimated to be less
than 100 million years old. This time period corresponds to Earth’s Cretaceous
period, the heyday of dinosaurs. Some areas may be less than 50 million years
old. Details of the study are published online in Sunday’s edition of Nature
Geoscience.
“This finding is the kind of science that is literally going to make
geologists rewrite the textbooks about the moon,” said John Keller, LRO project
scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
The deposits are scattered across the moon’s dark volcanic plains and are
characterized by a mixture of smooth, rounded, shallow mounds next to patches of
rough, blocky terrain. Because of this combination of textures, the researchers
refer to these unusual areas as irregular mare patches.
The features are too small to be seen from Earth, averaging less than a third
of a mile (500 meters) across in their largest dimension. One of the largest, a
well-studied area called Ina, was imaged from lunar orbit by Apollo 15
astronauts.
Ina appeared to be a one-of-a-kind feature until researchers from Arizona
State University in Tempe and Westfälische Wilhelms-Universität Münster in
Germany spotted many similar regions in high-resolution images taken by the two
Narrow Angle Cameras that are part of the Lunar Reconnaissance Orbiter Camera,
or LROC. The team identified a total of 70 irregular mare patches on the near
side of the moon.
The large number of these features and their wide distribution strongly
suggest that late-stage volcanic activity was not an anomaly but an important
part of the moon's geologic history.
The numbers and sizes of the craters within these areas indicate the deposits
are relatively recent. Based on a technique that links such crater measurements
to the ages of Apollo and Luna samples, three of the irregular mare patches are
thought to be less than 100 million years old, and perhaps less than 50 million
years old in the case of Ina. The steep slopes leading down from the smooth rock
layers to the rough terrain are consistent with the young age estimates.
In contrast, the volcanic plains surrounding these distinctive regions are
attributed to volcanic activity that started about 3 1/2 billion years ago and
ended roughly 1 billion years ago. At that point, all volcanic activity on the
moon was thought to cease.
Several earlier studies suggested that Ina was quite young and might have
formed due to localized volcanic activity. However, in the absence of other
similar features, Ina was not considered an indication of widespread
volcanism.
The findings have major implications for how warm the moon’s interior is
thought to be.
“The existence and age of the irregular mare patches tell us that the lunar
mantle had to remain hot enough to provide magma for the small-volume eruptions
that created these unusual young features,” said Sarah Braden, a recent Arizona
State University graduate and the lead author of the study.
The new information is hard to reconcile with what currently is thought about
the temperature of the interior of the moon.
“These young volcanic features are prime targets for future exploration, both
robotic and human,” said Mark Robinson, LROC principal investigator at Arizona
State University.
LRO is managed by Goddard for NASA’s Science Mission Directorate at NASA
Headquarters in Washington. LROC, a system of three cameras, was designed and
built by Malin Space Science Systems and is operated by Arizona State
University.
To access the complete collection of LROC images, visit
For more information about LRO, visit:
NASA
Guillermo Gonzalo Sánchez Achutegui
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