![Artist's concept of Europa (foreground), Jupiter (right) and Io (middle) Artist's concept of Europa (foreground), Jupiter (right) and Io (middle)](http://www.nasa.gov/images/content/731653main_pia16826-43_946-710.jpg)
his illustration of Europa (foreground), Jupiter (right) and Io (middle) is an artist's concept. Image credit: NASA/JPL-Caltech › Full image and caption
Taste of the Ocean on Europa's Surface
Based on new evidence from Jupiter's moon Europa, astronomers hypothesize that chloride salts bubble up from the icy moon's global liquid ocean and reach the frozen surface where they are bombarded with sulfur from volcanoes on Jupiter's innermost large moon Io. The new findings propose answers to questions that have been debated since the days of NASA's Voyager and Galileo missions. This illustration of Europa (foreground), Jupiter (right) and Io (middle) is an artist's concept.Credit: NASA/JPL-Caltech
![Jupiter’s moon Europa Jupiter’s moon Europa](http://www.nasa.gov/images/content/731666main_pia16827-43_946-710.jpg)
This view of Jupiter’s moon Europa
features several regional-resolution mosaics overlaid on a lower
resolution global view for context. Image credit:
NASA/JPL-Caltech/University of Arizona
› Full image and caption
› Full image and caption
Repeated Flybys Yield a Pole-to-Pole View of Europa
This view of Jupiter’s moon Europa features several regional-resolution mosaics overlaid on a lower resolution global view for context. The regional views were obtained during several different flybys of the moon by NASA's Galileo mission, and they stretch from high northern to high southern latitudes. Prominent here are the long, arcuate (or arc-shaped) and linear markings called lineae (Latin for strings or threads), which are a signature feature of Europa’s surface. Color saturation has been enhanced to bring out the subtle red coloration present along many of the lineae. The color data extends into the infrared, showing bluish ice (indicating larger ice grains) in the polar regions.The terrain in this view stretches from the side of Europa that always trails in its orbit at left (west), to the side that faces away from Jupiter at right (east). In addition to the lineae, the regional-scale images contain many interesting features, including lenticulae (small spots), chaos terrain, maculae (large spots), and the unusual bright band known as Agenor Linea in the south.
The regional-resolution mosaics enhance the amount of detail visible in a previously released view of the same region on Europa, PIA02590 . While the earlier image uses much of the same low-resolution data, its images are projected from a different angle and are processed with greater color saturation.
This view is an orthographic projection centered on 5.53 degrees south latitude, 214.5 degrees west longitude and has a resolution of 1,600 feet (500 meters) per pixel. An orthographic view is like the view seen by a distant observer looking through a telescope.
The mosaic was constructed from individual images obtained by the Solid State Imaging (SSI) system on NASA's Galileo spacecraft during six flybys of Europa between 1996 and 1999 (flybys designated G1, E11, E14, E15, E17, and E19).
Image credit: NASA/JPL-Caltech/University of Arizona
If you could lick the surface of Jupiter's icy moon Europa, you would
actually be sampling a bit of the ocean beneath. A new paper by Mike
Brown, an astronomer at the California Institute of Technology in
Pasadena, Calif., and Kevin Hand from NASA's Jet Propulsion Laboratory,
also in Pasadena, details the strongest evidence yet that salty water
from the vast liquid ocean beneath Europa's frozen exterior actually
makes its way to the surface.
The finding, based on some of the best data of its kind since NASA's
Galileo mission (1989 to 2003) to study Jupiter and its moons, suggests
there is a chemical exchange between the ocean and surface, making the
ocean a richer chemical environment. The work is described in a paper
that has been accepted for publication in the Astronomical Journal.
The exchange between the ocean and the surface, Brown said, "means that
energy might be going into the ocean, which is important in terms of the
possibilities for life there. It also means that if you'd like to know
what's in the ocean, you can just go to the surface and scrape some
off."
Europa's ocean is thought to cover the moon's whole globe and is about
60 miles (100 kilometers) thick under a thin ice shell. Since the days
of NASA's Voyager and Galileo missions, scientists have debated the
composition of Europa's surface. The infrared spectrometer aboard
Galileo was not capable of providing the detail needed to identify
definitively some of the materials present on the surface. Now, using
the Keck II Telescope on Mauna Kea, Hawaii, and its OSIRIS spectrometer,
Brown and Hand have identified a spectroscopic feature on Europa's
surface that indicates the presence of a magnesium sulfate salt, a
mineral called epsomite, that could have formed by oxidation of a
mineral likely originating from the ocean below.
Brown and Hand started by mapping the distribution of pure water ice
versus anything else. The spectra showed that even Europa's leading
hemisphere contains significant amounts of non-water ice. Then, at low
latitudes on the trailing hemisphere—the area with the greatest
concentration of the non-water ice material—they found a tiny,
never-before-detected dip in the spectrum.
The two researchers tested everything from sodium chloride to Drano in
Hand's lab at JPL, where he tries to simulate the environments found on
various icy worlds. At the end of the day, the signature of magnesium
sulfate persisted.
The magnesium sulfate appears to be generated by the irradiation of
sulfur ejected from the Jovian moon Io and, the authors deduce,
magnesium chloride salt originating from Europa's ocean. Chlorides such
as sodium and potassium chlorides, which are expected to be on the
Europa surface, are in general not detectable because they have no clear
infrared spectral features. But magnesium sulfate is detectable. The
authors believe the composition of Europa's ocean may closely resemble
the salty ocean of Earth.
Europa is considered a premier target in the search for life beyond
Earth, Hand said. A NASA-funded study team led by JPL and the Johns
Hopkins University Applied Physics Laboratory, Laurel, Md., has been
working with the scientific community to identify options to explore
Europa further. "If we've learned anything about life on Earth, it's
that where there's liquid water, there's generally life," Hand said.
"And of course our ocean is a nice, salty ocean. Perhaps Europa's salty
ocean is also a wonderful place for life."
The work was supported, in part, by the NASA Astrobiology Institute
through the Icy Worlds team based at JPL, a division of Caltech. The
NASA Astrobiology Institute, based at NASA's Ames Research Center,
Moffett Field, Calif., is a partnership among NASA, 15 U.S. teams, and
13 international consortia. The NAI is part of NASA's Astrobiology
program, which supports research into the origin, evolution,
distribution and future of life on Earth and the potential for life
elsewhere.
NASA Awards Human Health and Performance Contract
WASHINGTON
-- NASA has selected Wyle Laboratories Inc. of Houston to provide
biomedical, medical and health services in support of all human
spaceflight programs at the agency's Johnson Space Center in Houston.
The contract begins May 1 and has a maximum potential value of $1.76 billion. This indefinite-delivery, indefinite-quantity contract with cost-plus-award-fee task orders has a five-year base period and two option periods that could extend the contract through 2023.
The new Human Health and Performance contract will support many NASA programs and offices including the International Space Station, Orion, Advanced Exploration Systems, Space Technology Mission Directorate, Human Research Program and Commercial Crew and Cargo programs.
Services provided under this contract include fundamental and applied biomedical research; biotechnology development; operational space medicine; occupational health and medicine; and management of clinical, biomedical, space food and environmental laboratories. The contractor also will support behavioral sciences; human factors engineering; spacecraft environment monitoring and management; biomedical engineering; biomedical flight hardware requirements, design, fabrication, testing and operation; and payload and hardware integration with the International Space Station.
Lockheed Martin Services Inc., of Gaithersburg, Md., is a subcontractor. Services will be performed at Johnson and Wyle facilities.
For more information about NASA and agency programs, visit:
The contract begins May 1 and has a maximum potential value of $1.76 billion. This indefinite-delivery, indefinite-quantity contract with cost-plus-award-fee task orders has a five-year base period and two option periods that could extend the contract through 2023.
The new Human Health and Performance contract will support many NASA programs and offices including the International Space Station, Orion, Advanced Exploration Systems, Space Technology Mission Directorate, Human Research Program and Commercial Crew and Cargo programs.
Services provided under this contract include fundamental and applied biomedical research; biotechnology development; operational space medicine; occupational health and medicine; and management of clinical, biomedical, space food and environmental laboratories. The contractor also will support behavioral sciences; human factors engineering; spacecraft environment monitoring and management; biomedical engineering; biomedical flight hardware requirements, design, fabrication, testing and operation; and payload and hardware integration with the International Space Station.
Lockheed Martin Services Inc., of Gaithersburg, Md., is a subcontractor. Services will be performed at Johnson and Wyle facilities.
For more information about NASA and agency programs, visit:
Jia-Rui Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jccook@jpl.nasa.gov
Brian Bell 626-395-5832
California Institute of Technology
bbell2@caltech.edu
Jet Propulsion Laboratory, Pasadena, Calif.
jccook@jpl.nasa.gov
Brian Bell 626-395-5832
California Institute of Technology
bbell2@caltech.edu
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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