Hi My Friends: A VUELO DE UN QUINDE EL BLOG., WASHINGTON -- Data from a NASA planetary mission have provided scientists evidence of what appears to be a body of liquid water, equal in volume to the North American Great Lakes, beneath the icy surface of Jupiter's moon, Europa. The data suggest there is significant exchange between Europa's icy shell and the ocean beneath. This information could bolster arguments that Europa's global subsurface ocean represents a potential habitat for life elsewhere in our solar system. The findings are published in the scientific journal Nature. "The data opens up some compelling possibilities," said Mary Voytek, director of NASA's Astrobiology Program at agency headquarters in Washington. "However, scientists worldwide will want to take a close look at this analysis and review the data before we can fully appreciate the implication of these results." NASA's Galileo spacecraft, launched by the space shuttle Atlantis in 1989 to Jupiter, produced numerous discoveries and provided scientists decades of data to analyze. Galileo studied Jupiter, which is the most massive planet in the solar system, and some of its many moons. One of the most significant discoveries was the inference of a global salt water ocean below the surface of Europa. This ocean is deep enough to cover the whole surface of Europa and contains more liquid water than all of Earth's oceans combined. However, being far from the sun, the ocean surface is completely frozen. Most scientists think this ice crust is tens of miles thick. "One opinion in the scientific community has been if the ice shell is thick, that's bad for biology. That might mean the surface isn't communicating with the underlying ocean," said Britney Schmidt, lead author of the paper and postdoctoral fellow at the Institute for Geophysics, University of Texas at Austin. "Now, we see evidence that it's a thick ice shell that can mix vigorously and new evidence for giant shallow lakes. That could make Europa and its ocean more habitable." Schmidt and her team focused on Galileo images of two roughly circular, bumpy features on Europa's surface called chaos terrains. Based on similar processes seen on Earth -- on ice shelves and under glaciers overlaying volcanoes -- they developed a four-step model to explain how the features form. The model resolves several conflicting observations. Some seemed to suggest the ice shell is thick. Others suggest it is thin. This recent analysis shows the chaos features on Europa's surface may be formed by mechanisms that involve significant exchange between the icy shell and the underlying lake. This provides a mechanism or model for transferring nutrients and energy between the surface and the vast global ocean already inferred to exist below the thick ice shell. This is thought to increase the potential for life there. The study authors have good reason to believe their model is correct, based on observations of Europa from Galileo and of Earth. Still, because the inferred lakes are several miles below the surface, the only true confirmation of their presence would come from a future spacecraft mission designed to probe the ice shell. Such a mission was rated as the second highest priority flagship mission by the National Research Council's recent Planetary Science Decadal Survey and is being studied by NASA. "This new understanding of processes on Europa would not have been possible without the foundation of the last 20 years of observations over Earth's ice sheets and floating ice shelves," said Don Blankenship, a co-author and senior research scientist at the Institute for Geophysics, where he leads airborne radar studies of the planet's ice sheets. Galileo was the first spacecraft to directly measure Jupiter's atmosphere with a probe and conduct long-term observations of the Jovian system. The probe was the first to fly by an asteroid and discover the moon of an asteroid. NASA extended the mission three times to take advantage of Galileo's unique science capabilities, and it was put on a collision course into Jupiter's atmosphere in September 2003 to eliminate any chance of impacting Europa. The Galileo mission was managed by NASA's Jet Propulsion Laboratory in Pasadena, Calif., for the agency's Science Mission Directorate. For images and a video animation of the findings, visit:
http://tinyurl.com/csukksm
http://tinyurl.com/csukksm
Europa's "Great Lake." Researchers predict many more such lakes are scattered throughout the moon's icy shell. Credit: Britney Schmidt/Dead Pixel VFX/Univ. of Texas at Austin.Scientists Find Evidence for “Great Lake” on Europa and Potential New Habitat for Life:
Watch animation of how lakes form inside Europa’s icy shell.
http://www.jsg.utexas.edu/news/2011/11/scientists-find-evidence-for-great-lake-on-europa/
In a significant finding in the search for life beyond Earth, scientists from The University of Texas at Austin and elsewhere have discovered what appears to be a body of liquid water the volume of the North American Great Lakes locked inside the icy shell of Jupiter’s moon Europa.
The water could represent a potential habitat for life, and many more such lakes might exist throughout the shallow regions of Europa’s shell, lead author Britney Schmidt, a postdoctoral fellow at The University of Texas at Austin’s Institute for Geophysics, writes in the journal Nature.
Further increasing the potential for life, the newly discovered lake is covered by floating ice shelves that seem to be collapsing, providing a mechanism for transferring nutrients and energy between the surface and a vast ocean already inferred to exist below the thick ice shell.
“One opinion in the scientific community has been, ‘If the ice shell is thick, that’s bad for biology — that it might mean the surface isn’t communicating with the underlying ocean,’ ” said Schmidt. “Now we see evidence that even though the ice shell is thick, it can mix vigorously. That could make Europa and its ocean more habitable.”
The scientists focused on Galileo spacecraft images of two roughly circular, bumpy features on Europa’s surface called chaos terrains. Based on similar processes seen here on Earth — on ice shelves and under glaciers overlaying volcanoes — the researchers developed a four-step model to explain how the features form on Europa. It resolves several conflicting observations, some of which seemed to suggest that the ice shell is thick and others that it is thin.
“I read the paper and immediately thought, yes, that’s it, that makes sense,” said Robert Pappalardo, senior research scientist at NASA’s Planetary Science Section who did not participate in the study. “It’s the only convincing model that fits the full range of observations. To me, that says yes, that’s the right answer.”
The scientists have good reason to believe their model is correct, based on observations of Europa from the Galileo spacecraft and of Earth. Still, because the inferred lakes are several kilometers below the surface, the only true confirmation of their presence would come from a future spacecraft mission designed to probe the ice shell. Such a mission was rated as the second-highest priority flagship mission by the National Research Council’s recent Planetary Science Decadal Survey and is currently being studied by NASA. On Earth, radar instruments are used to image similar features within the ice, and are among the instruments being considered for a future Europa mission.
“This new understanding of processes on Europa would not have been possible without the foundation of the last 20 years of observations over Earth’s ice sheets and floating ice shelves,” said Don Blankenship, a co-author and senior research scientist at the Institute for Geophysics, where he leads airborne radar studies of Earth’s ice sheets.
Schmidt and Blankenship’s co-authors are Wes Patterson, planetary scientist at the Johns Hopkins University Applied Physics Laboratory, and Paul Schenk, planetary scientist at the Lunar and Planetary Institute in Houston.
The research was funded by the Institute for Geophysics at The University of Texas at Austin’s Jackson School of Geosciences, the Vetlesen Foundation and NASA.
The paper, “Active formation of ‘chaos terrain’ over shallow subsurface water on Europa,” will appear as an advance online publication of the journal Nature on Nov. 16.
Video
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
In a significant finding in the search for life beyond Earth, scientists from The University of Texas at Austin and elsewhere have discovered what appears to be a body of liquid water the volume of the North American Great Lakes locked inside the icy shell of Jupiter’s moon Europa.
The water could represent a potential habitat for life, and many more such lakes might exist throughout the shallow regions of Europa’s shell, lead author Britney Schmidt, a postdoctoral fellow at The University of Texas at Austin’s Institute for Geophysics, writes in the journal Nature.
Further increasing the potential for life, the newly discovered lake is covered by floating ice shelves that seem to be collapsing, providing a mechanism for transferring nutrients and energy between the surface and a vast ocean already inferred to exist below the thick ice shell.
“One opinion in the scientific community has been, ‘If the ice shell is thick, that’s bad for biology — that it might mean the surface isn’t communicating with the underlying ocean,’ ” said Schmidt. “Now we see evidence that even though the ice shell is thick, it can mix vigorously. That could make Europa and its ocean more habitable.”
The scientists focused on Galileo spacecraft images of two roughly circular, bumpy features on Europa’s surface called chaos terrains. Based on similar processes seen here on Earth — on ice shelves and under glaciers overlaying volcanoes — the researchers developed a four-step model to explain how the features form on Europa. It resolves several conflicting observations, some of which seemed to suggest that the ice shell is thick and others that it is thin.
“I read the paper and immediately thought, yes, that’s it, that makes sense,” said Robert Pappalardo, senior research scientist at NASA’s Planetary Science Section who did not participate in the study. “It’s the only convincing model that fits the full range of observations. To me, that says yes, that’s the right answer.”
The scientists have good reason to believe their model is correct, based on observations of Europa from the Galileo spacecraft and of Earth. Still, because the inferred lakes are several kilometers below the surface, the only true confirmation of their presence would come from a future spacecraft mission designed to probe the ice shell. Such a mission was rated as the second-highest priority flagship mission by the National Research Council’s recent Planetary Science Decadal Survey and is currently being studied by NASA. On Earth, radar instruments are used to image similar features within the ice, and are among the instruments being considered for a future Europa mission.
“This new understanding of processes on Europa would not have been possible without the foundation of the last 20 years of observations over Earth’s ice sheets and floating ice shelves,” said Don Blankenship, a co-author and senior research scientist at the Institute for Geophysics, where he leads airborne radar studies of Earth’s ice sheets.
Schmidt and Blankenship’s co-authors are Wes Patterson, planetary scientist at the Johns Hopkins University Applied Physics Laboratory, and Paul Schenk, planetary scientist at the Lunar and Planetary Institute in Houston.
The research was funded by the Institute for Geophysics at The University of Texas at Austin’s Jackson School of Geosciences, the Vetlesen Foundation and NASA.
The paper, “Active formation of ‘chaos terrain’ over shallow subsurface water on Europa,” will appear as an advance online publication of the journal Nature on Nov. 16.
Video
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
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