Uma montanha em particular em Marte, maior do que a mais grandiosa do Colorado, foi avistada pela primeira vez em órbita na década de 1970. Os cientistas têm idéia sobre como ela se formou no meio da cratera Gale.
O nome Monte Sharp é uma homenagem ao geólogo Robert P. A. Sharp (1911-2004), fundador da ciência planetária, professor influente de muitos líderes atuais na área.
Sharp ensinou geologia no Instituto de Tecnologia da Califórnia (Caltech), em Pasadena, a partir de 1948 até sua aposentadoria. A Revista Life o classificou como um dos 10 melhores professores universitários do país.
"Bob Sharp foi um dos melhores geólogos de campo que este país já teve", disse Michael Malin, do Malin Space Science Systems, San Diego.
"Nós realmente não sabemos as origens do Monte Sharp, mas temos planos para como ir lá e testar nossas teorias sobre isso, e Bob teria gostado isso", disse Malin.
Caltech Provost Edward Stolper, ex-cientista-chefe para o Mars Science Laboratory, disse: "Na maior parte de seus mais de 50 anos em Caltech, Bob Sharp foi a figura central em seus programas nas ciências geológicas e planetária. Uma de suas maiores contribuições foi a construção de um programa de ciências planetárias firmemente alicerçado nos princípios e abordagens das ciências geológicas.
"Além disso, através de seu trabalho sobre primeiras missões do Jet Propulsion Laboratory de Marte e do trabalho dos outros que ele influenciou, ele também teve uma grande influência sobre ciência planetária e exploração no JPL. O reconhecimento deste notável cientista e líder com a nomeação de Monte Sharp é altamente apropriado, e espero que sirva para perpetuar o seu legado. "
Várias crateras em Marte contêm montes ou chapadas que se formaram de maneira semelhante ao Monte Sharp, e muitas outras crateras antigas permanecem cheias ou enterradas por camadas de rocha.
One particular mountain on Mars, bigger than Colorado's grandest, has
been beckoning would-be explorers since it was first sighted from orbit
in the 1970s. Scientists have ideas about how it took shape in the
middle of ancient Gale Crater and hopes for what evidence it could
yield about whether conditions on Mars have favored life.
No mission to Mars dared approach it, though, until NASA's Mars Science Laboratory mission, which this August will attempt to place its one-ton rover, Curiosity, at the foot of the mountain. The moat of flatter ground between the mountain and the crater rim encircling it makes too small a touchdown target to have been considered safe without precision-landing innovations used by this mission.
To focus discussions about how Curiosity will explore the mountain during a two-year prime mission after landing, the mission's international Project Science Group has decided to call it Mount Sharp. This informal naming pays tribute to geologist Robert P. Sharp (1911-2004), a founder of planetary science, influential teacher of many current leaders in the field, and team member for NASA's first few Mars missions. Sharp taught geology at the California Institute of Technology (Caltech), in Pasadena, from 1948 until past his retirement. Life magazine named him one of the 10 best college teachers in the nation.
"Bob Sharp was one of the best field geologists this country has ever had," said Michael Malin, of Malin Space Science Systems, San Diego, principal investigator for two of Curiosity's 10 science instruments and a former student of Sharp's.
"We don't really know the origins of Mount Sharp, but we have plans for how to go there and test our theories about it, and that's just how Bob would have wanted it," Malin said.
Caltech Provost Edward Stolper, former chief scientist for the Mars Science Laboratory, said, "For much of his more than 50 years at Caltech, Bob Sharp was the central figure in its programs in the geological and planetary sciences. One of his major contributions was the building of a program in planetary sciences firmly rooted in the principles and approaches of the geological sciences.
"Moreover, through his own work on the Jet Propulsion Laboratory's early missions to Mars and the work of others that he influenced, he also had a major influence on planetary science and exploration at JPL. Recognition of this remarkable scientist and leader by the naming of Mount Sharp is highly fitting, and I hope it will serve to perpetuate his legacy."
The Mars Science Laboratory spacecraft was launched Nov. 26, 2011, bound for landing beside Mount Sharp inside Gale Crater on the evening of Aug. 5, PST (early Aug. 6, EST and Universal Time). The mission will use Curiosity to investigate whether the area has ever offered environmental conditions favorable for fostering microbial life, including chemical ingredients for life and energy for life.
Mount Sharp rises about 3 miles (5 kilometers) above the landing target on the crater floor, higher than Mount Rainier above Seattle, though broader and closer. It is not simply a rebound peak from the asteroid impact that excavated Gale Crater. A rebound peak may be at its core, but the mountain displays hundreds of flat-lying geological layers that may be read as chapters in a more complex history billions of years old.
Twice as tall as the sequence of colorful bands exposed in Arizona's Grand Canyon, the stack of layers in Mount Sharp results from changing environments in which layers are deposited, younger on top of older, eon after eon, and then partially eroded away.
Several craters on Mars contain mounds or mesas that may have formed in ways similar to Mount Sharp, and many other ancient craters remain filled or buried by rock layers. Some examples, including Gale, hold a mound higher than the surrounding crater rim, indicating that the mounds are remnant masses inside once completely filled craters. This presents a puzzle about how environmental conditions on Mars evolved.
"This family of craters that were filled or buried and then exhumed or partially exhumed raises the question of what changed," said Ken Edgett of Malin Space Sciences, principal investigator for one of Curiosity's instruments. "For a long time, sedimentary materials enter the crater and stay. Then, after they harden into rock, somehow the rock gets eroded away and transported out of the crater."
Some lower layers of Mount Sharp might tell of a lake within Gale Crater long ago, or wind-delivered sediments subsequently soaked by groundwater. Orbiters have mapped water-telltale minerals in those layers. Liquid water is a starting point in describing conditions favorable for life, but just the beginning of what Curiosity can investigate. Higher layers may be deposits of wind-blown dust after a great drying-out on Mars.
"Mount Sharp is the only place we can currently access on Mars where we can investigate this transition in one stratigraphic sequence," said Caltech's John Grotzinger, chief scientist for the Mars Science Laboratory. "The hope of this mission is to find evidence of a habitable environment; the promise is to get the story of an important environmental breakpoint in the deep history of the planet. This transition likely occurred billions of years ago -- maybe even predating the oldest well-preserved rocks on Earth."
No mission to Mars dared approach it, though, until NASA's Mars Science Laboratory mission, which this August will attempt to place its one-ton rover, Curiosity, at the foot of the mountain. The moat of flatter ground between the mountain and the crater rim encircling it makes too small a touchdown target to have been considered safe without precision-landing innovations used by this mission.
To focus discussions about how Curiosity will explore the mountain during a two-year prime mission after landing, the mission's international Project Science Group has decided to call it Mount Sharp. This informal naming pays tribute to geologist Robert P. Sharp (1911-2004), a founder of planetary science, influential teacher of many current leaders in the field, and team member for NASA's first few Mars missions. Sharp taught geology at the California Institute of Technology (Caltech), in Pasadena, from 1948 until past his retirement. Life magazine named him one of the 10 best college teachers in the nation.
"Bob Sharp was one of the best field geologists this country has ever had," said Michael Malin, of Malin Space Science Systems, San Diego, principal investigator for two of Curiosity's 10 science instruments and a former student of Sharp's.
"We don't really know the origins of Mount Sharp, but we have plans for how to go there and test our theories about it, and that's just how Bob would have wanted it," Malin said.
Caltech Provost Edward Stolper, former chief scientist for the Mars Science Laboratory, said, "For much of his more than 50 years at Caltech, Bob Sharp was the central figure in its programs in the geological and planetary sciences. One of his major contributions was the building of a program in planetary sciences firmly rooted in the principles and approaches of the geological sciences.
"Moreover, through his own work on the Jet Propulsion Laboratory's early missions to Mars and the work of others that he influenced, he also had a major influence on planetary science and exploration at JPL. Recognition of this remarkable scientist and leader by the naming of Mount Sharp is highly fitting, and I hope it will serve to perpetuate his legacy."
The Mars Science Laboratory spacecraft was launched Nov. 26, 2011, bound for landing beside Mount Sharp inside Gale Crater on the evening of Aug. 5, PST (early Aug. 6, EST and Universal Time). The mission will use Curiosity to investigate whether the area has ever offered environmental conditions favorable for fostering microbial life, including chemical ingredients for life and energy for life.
Mount Sharp rises about 3 miles (5 kilometers) above the landing target on the crater floor, higher than Mount Rainier above Seattle, though broader and closer. It is not simply a rebound peak from the asteroid impact that excavated Gale Crater. A rebound peak may be at its core, but the mountain displays hundreds of flat-lying geological layers that may be read as chapters in a more complex history billions of years old.
Twice as tall as the sequence of colorful bands exposed in Arizona's Grand Canyon, the stack of layers in Mount Sharp results from changing environments in which layers are deposited, younger on top of older, eon after eon, and then partially eroded away.
Several craters on Mars contain mounds or mesas that may have formed in ways similar to Mount Sharp, and many other ancient craters remain filled or buried by rock layers. Some examples, including Gale, hold a mound higher than the surrounding crater rim, indicating that the mounds are remnant masses inside once completely filled craters. This presents a puzzle about how environmental conditions on Mars evolved.
"This family of craters that were filled or buried and then exhumed or partially exhumed raises the question of what changed," said Ken Edgett of Malin Space Sciences, principal investigator for one of Curiosity's instruments. "For a long time, sedimentary materials enter the crater and stay. Then, after they harden into rock, somehow the rock gets eroded away and transported out of the crater."
Some lower layers of Mount Sharp might tell of a lake within Gale Crater long ago, or wind-delivered sediments subsequently soaked by groundwater. Orbiters have mapped water-telltale minerals in those layers. Liquid water is a starting point in describing conditions favorable for life, but just the beginning of what Curiosity can investigate. Higher layers may be deposits of wind-blown dust after a great drying-out on Mars.
"Mount Sharp is the only place we can currently access on Mars where we can investigate this transition in one stratigraphic sequence," said Caltech's John Grotzinger, chief scientist for the Mars Science Laboratory. "The hope of this mission is to find evidence of a habitable environment; the promise is to get the story of an important environmental breakpoint in the deep history of the planet. This transition likely occurred billions of years ago -- maybe even predating the oldest well-preserved rocks on Earth."
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