SpaceJibe

April 14, 2017

Saturn’s Moon Enceladus Shows More Signs It Could Support Alien Life

Filed under: Cool, Extraterrestrial Life, Life, Moon, Saturn — bferrari @ 9:07 am

Saturn’s icy moon Enceladus is looking more and more like a habitable world.

The same sorts of chemical reactions that sustain life near deep-sea hydrothermal vents here on Earth could potentially be occurring within Enceladus’ subsurface ocean, a new study published today (April 13) in the journal Science suggests.

These reactions depend on the presence of molecular hydrogen (H2), which, the new study reports, is likely being produced continuously by reactions between hot water and rock deep down in Enceladus’ sea.

Related: Photos of Enceladus, Saturn’s Geyser-Blasting Moon

“The abundance of H2, along with previously observed carbonate species, suggests a state of chemical disequilibria in the Enceladus ocean that represents a chemical energy source capable of supporting life,” Jeffrey Seewald, of the Marine Chemistry and Geochemistry Department at the Woods Hole Oceanographic Institution in Massachusetts, wrote in an accompanying “Perspectives” piece in the same issue of Science. (Seewald was not involved in the new Enceladus study.)

A Geyser-Blasting Ocean World

The 313-mile-wide (504 kilometers) Enceladus is just Saturn’s sixth-largest moon, but the object has loomed large in the minds of astrobiologists since 2005.

In that year, NASA’s Saturn-orbiting Cassini spacecraft first spotted geysers of water ice erupting from “tiger stripe” fissures near Enceladus’ south pole. Scientists think these geysers are blasting material from a sizeable ocean buried beneath the satellite’s ice shell.

So, Enceladus has liquid water, one of the key ingredients required for life as we know it. (This ocean stays liquid because Saturn’s immense gravitational pull twists and stretches the moon, generating internal “tidal” heat.) And the new study suggests that the satellite possesses another key ingredient as well: an energy source.

 

A team of researchers led by Hunter Waite, of the Southwest Research Institute (SwRI) in San Antonio, analyzed observations made by Cassini during an October 2015 dive through Enceladus’ geyser plume.

This plunge was special in several ways. For one thing, it was Cassini’s deepest-ever dive through the plume; the probe got within a mere 30 miles (49 km) of Enceladus’ surface. In addition, Cassini’s Ion and Neutral Mass Spectrometer (INMS) instrument alternated between “open-source” and “closed-source” modes during the encounter, rather than sticking to closed source (the usual routine).

INMS is just 0.25 percent as sensitive in open-source mode as it is in closed-source mode, Waite and his colleagues wrote in the new Science paper. But open source has a key advantage: It minimizes artifacts that have complicated previous attempts to measure H2 levels in the plume.

With this analytical hurdle cleared, Waite and his team were able to calculate that H2 makes up between 0.4 percent and 1.4 percent of the volume of Enceladus’ geyser plume. Further calculations revealed that carbon dioxide (CO2) makes up an additional 0.3 percent to 0.8 percent of the plume’s volume.

Related: Inside Enceladus, Icy Moon of Saturn (Infographic)

The molecular hydrogen is most likely being produced continuously by reactions between hot water and rock in and around Enceladus’ core, Waite and his colleagues concluded. They considered other possible explanations and found them wanting. For example, neither Enceladus’ ocean nor its ice shell are viable long-term reservoirs for volatile H2, the authors wrote, and processes that disassociate H2 from water ice in the shell don’t seem capable of generating the volume measured in the plume.

The hydrothermal explanation is also consistent with a 2016 study by another research group, which concluded that tiny silica grains detected by Cassini could have been produced only in hot water at significant depths.

“The story seems to be fitting together,” Chris Glein of SwRI, a co-author of the new Science paper, told Space.com.

Deep-Sea Chemical Reactions

Earth’s deep-sea hydrothermal vents support rich communities of life, ecosystems powered by chemical energy rather than sunlight.

“Some of the most primitive metabolic pathways utilized by microbes in these environments involve the reduction of carbon dioxide (CO2) with H2 to form methane (CH4) by a process known as methanogenesis,” Seewald wrote.

The inferred presence of H2 and CO2 in Enceladus’ ocean therefore suggests that similar reactions could well be occurring deep beneath the moon’s icy shell. Indeed, the observed H2 levels indicate that a lot of chemical energy is potentially available in the ocean, Glein said.

“It’s quite a bit larger than the minimum energy required to support methanogenesis,” he said.

Glein stressed, however, that nobody knows whether such reactions are actually occurring on Enceladus.

“This is not a detection of life,” Glein said. “It increases the habitability, but I would never suggest that this makes Enceladus more or less likely to have life itself. I think the only way to answer that question is, we need data.”

Seewald also counseled caution on astrobiological interpretations. He noted, for example, that molecular hydrogen is rare in Earth’s seawater, because hungry microbes quickly gobble it up.

“Is the presence of H2 in the Enceladus ocean an indicator for the absence of life, or is it a reflection of the very different geochemical environment and associated ecosystems on Enceladus?” Seewald wrote. “We still have a long way to go in our understanding of processes regulating the exchange of mass and heat across geological interfaces that define the internal structure of Enceladus and other ice-covered planetary bodies.”

Originally published on Space.com.

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January 24, 2016

Particles could reveal clues to how Egypt pyramid was built

Filed under: Cool, Cosmology, Gadgets, Planets, Wierd — bferrari @ 11:29 am
FILE - This file Aug. 19, 2011 photo shows the Bent Pyramid at Dahshur, about 25 miles south of Cairo, Egypt. (AP Photo/Coralie Carlson, File)

FILE – This file Aug. 19, 2011 photo shows the Bent Pyramid at Dahshur, about 25 miles south of Cairo, Egypt. (AP Photo/Coralie Carlson, File)

CAIRO — An international team of researchers said Sunday they will soon begin analyzing cosmic particles collected inside Egypt’s Bent Pyramid to search for clues as to how it was built and learn more about the 4,600-year-old structure.

Mehdi Tayoubi, president of the Heritage Innovation Preservation Institute, said that plates planted inside the pyramid last month have collected data on radiographic particles known as muons that rain down from the earth’s atmosphere.

The particles pass through empty spaces but can be absorbed or deflected by harder surfaces. By studying particle accumulations, scientists may learn more about the construction of the pyramid, built by the Pharaoh Snefru.

“For the construction of the pyramids, there is no single theory that is 100 percent proven or checked; They are all theories and hypotheses,” said Hany Helal, the institute’s vice president.

“What we are trying to do with the new technology, we would like to either confirm or change or upgrade or modify the hypotheses that we have on how the pyramids were constructed,” he said.

The Bent Pyramid in Dahshur, just outside Cairo, is distinguished by the bent slope of its sides. It is believed to have been ancient Egypt’s first attempt to build a smooth-sided pyramid.

The Scan Pyramids project, which announced in November thermal anomalies in the 4,500 year-old Khufu Pyramid in Giza, is coupling thermal technology with muons analysis to try to unlock secrets to the construction of several ancient Egyptian pyramids.

Tayoubi said the group plans to start preparations for muons testing in a month in Khufu, the largest of the three Giza pyramids, which is known internationally as Cheops.

“Even if we find one square meter void somewhere, it will bring new questions and hypotheses and maybe it will help solve the definitive questions,” said Tayoubi.

Source

December 18, 2015

Wolf 1061 exoplanet: ‘Super-Earth’ discovered only 14 light-years away

Filed under: Cool, Exoplanets, Extraterrestrial Life, Planets — bferrari @ 10:54 am

Alien life could be closer to us than previously thought. Scientists have just discovered the nearest habitable planet to Earth.

The new world is one of three surrounding a red dwarf star called Wolf 1061, which is just 14 light years away. It was detected by scientists at the University of New South Wales (UNSW) in Australia.

All three planets have the potential to be solid and rocky, but only Wolf 1061c exists within the “Goldilocks zone” — a distance from the star (much smaller and cooler than our sun) that is not too hot and not too cold for liquid water.

“This rare discovery is incredibly exciting,” UNSW’s Duncan Wright, who led the study, told CNN.

“Other planets found that are habitable are not nearly this close to Earth. Because of the close proximity of this planet to us, there is good opportunity to find out more about it.”

“The close proximity of the planets around Wolf 1061 means there is a good chance these planets may pass across the face of the star,” UNSW team member Rob Wittenmyer said in an earlier statement.

“If they do, then it may be possible to study the atmospheres of these planets in future to see whether they would be conducive to life.”

151217121358-wolf-1061-space-super-169

NASA has confirmed more than 1,870 exoplanets — worlds outside our solar system. But this discovery is particularly important because Wolf 1061c is both habitable and close to our solar system.

December 31, 2014

What the view from earth would be like if earth had rings like Saturn

Filed under: Cool, Earth, Saturn — bferrari @ 5:22 pm

May 12, 2014

Solar siblings? Astronomers discover sun’s long-lost brother

Filed under: Cool, Cosmology, Saturn — bferrari @ 6:55 am
The star HD 162826 is probably a

The star HD 162826 is probably a “solar sibling,” that is, a star born in the same star cluster as the sun. It was identified by University of Texas at Austin astronomer Ivan Ramirez, in the process of honing a technique to find more solar siblings in the future, and eventually to determine how and where in the Milky Way galaxy the sun formed. (IVAN RAMIREZ/TIM JONES/MCDONALD OBSERVATORY)

It turns out that the sun has a long-lost brother — and now astronomers are racing to map a solar family tree.

new study from researchers at the University of Texas provides clues as to how our sun was formed, whether there are other “solar siblings” in our universe and, perhaps, a better understanding of how life in the universe was formed billions of years ago.

The finding, which will be published next month in The Astrophysical Journal, identifies a star that was almost certainly born from the same cloud of gas and dust as the sun. Located 110 light years away in the constellation Hercules, the star, called HD 162826, is 15 percent more massive than our sun, and can be seen with low-power binoculars.

“We want to know where we were born,” University of Texas at Austin astronomer Ivan Ramirez said in a news release from McDonald Observatory. “If we can figure out in what part of the galaxy the sun formed, we can constrain conditions on the early solar system. That could help us understand why we are here.”

Ramirez and his eight-person team discovered HD 162826’s relation to the sun by following up on 30 possible candidates found by several groups around the world looking for solar siblings. Ramirez’s team studied 23 stars in-depth at McDonald Observatory and several stars, visible only from the southern hemisphere, using the Clay Magellan Telescope at Las Campanas Observatory in Chile. Both observations required the use of high-resolution spectorscopy to understand the stars’ chemical makeup.

There’s even a small chance these solar siblings could host life-sustaining planets. When these stars were born, collisions could have knocked chunks off planets, and these fragments could have traveled between solar systems — perhaps bringing primitive life to Earth. Conversely, fragments from Earth could have sent life to planets orbiting other stars.

“It could be argued that solar siblings are the key candidates in the search for extraterrestrial life,” Ramirez said.

Next, Ramirez’s team wants to create a road map for how to identify solar siblings, operating on the theory that the sun was born in a cluster with up to 100,000 stars. That cluster, however, formed more than 4.5 billion years ago, and has long since broken up, spreading the stars out to different parts of the Milky Way galaxy. Finding more solar siblings will provide the best clues toward discovering our sun’s origin, and Ramirez’s discovery is an important step in streamlining the identification process when it comes to tracking down stars with the same galactic DNA, he told FoxNews.com on Friday.

“Already, we’re getting a lot of data from a number of surveys,” Ramirez told FoxNews.com on Friday. “In five to 10 years from now, we’re going to be able to analyze 10,000 times more stars than what we’re able to do right now.”

Source

March 5, 2014

Artist's concept of Europa water vapor plume. Image: NASA/ESA/K. Retherford/SWRI

Artist’s concept of Europa water vapor plume. Image: NASA/ESA/K. Retherford/SWRI

ALL THESE WORLDS ARE YOURS EXCEPT EUROPA ATTEMPT NO LANDING THERE.

That warning, as given in Arthur C. Clarke’s 2010: Odyssey Two novel, was pretty explicit but apparently it is going to go unheeded by NASA.

According to Space.com, NASA wants to launch a mission to Europa by 2025. Yesterday’s White House 2015 federal budget request allocates $15 million to develop a space program to visit the icy moon of Jupiter, which has a potentially life-supporting ocean of liquid water underneath its icy exterior.

“Europa is a very challenging mission operating in a really high radiation environment, and there’s lots to do to prepare for it,” said NASA chief financial officer Beth Robinson. “We’re looking to launch sometime in the mid-2020s.”

While the space program is wide open, one candidate project is NASA’s Europa Clipper, a probe that would orbit Jupiter and make flyby trips to Europa to study the moon’s environment. An exciting potential is to have the probe cruise through Europa’s 125-mile-high water plumes, spotted by Hubble back in December 2013, to collect and analyze samples.

Artist's concept of the Europa Clipper mission. Image: NASA/JPL-Caltech

Artist’s concept of the Europa Clipper mission. Image: NASA/JPL-Caltech

December 15, 2012

‘Nile river’ discovered on Saturn moon Titan — first river on another planet

Dec. 12, 2012: NASA's Cassini spacecraft has discovered a vast river system on Saturn's moon Titan. It is the first time images from space have revealed a river system so vast and in such high resolution anywhere other than Earth (NASA/JPL-Caltech/ASI)

Dec. 12, 2012: NASA’s Cassini spacecraft has discovered a vast river system on Saturn’s moon Titan. It is the first time images from space have revealed a river system so vast and in such high resolution anywhere other than Earth (NASA/JPL-Caltech/ASI)

The Cassini Solstice mission has discovered what appears to be a miniature version of the Nile River on Saturn’s largest moon, Titan. In comparison, the Nile is 4,132 miles long. The 250-mile long feature — from ‘headwaters’ to a large sea — is the longest extraterrestrial river ever to be discovered and imaged to such high resolution.

Using Cassini’s radar imaging instruments, mission scientists were able to deduce that the feature is indeed a river as the dark, smooth surface within the meanders and channel suggest the presence of a liquid.

ANALYSIS: The ‘Tropical’ Lakes of Saturn’s Moon Titan

 

‘The relative straightness of the river valley suggests it follows the trace of at least one fault, similar to other large rivers.’

– Jani Radebaugh, Cassini radar team associate at Brigham Young University

 

Titan is known to have vast lakes — the only other body in the solar system, apart from Earth, to possess a cycle of liquids on its surface. However, the thick Titan atmosphere is a frigid one, meaning liquid water couldn’t possibly flow. The liquids on Titan are therefore composed of hydrocarbons such as methane and ethane.

Interestingly, using this observation of a vast river system on Titan reveals not only that rivers flow, it could also trace the path of fault lines on the Saturnian moon, suggestive of fractures in Titan’s bedrock.

“Though there are some short, local meanders, the relative straightness of the river valley suggests it follows the trace of at least one fault, similar to other large rivers running into the southern margin of this same Titan sea,” said Jani Radebaugh, Cassini radar team associate at Brigham Young University.

“Such faults — fractures in Titan’s bedrock — may not imply plate tectonics, like on Earth, but still lead to the opening of basins and perhaps to the formation of the giant seas themselves.”

ANALYSIS: Need a Vacation? Visit Titan’s Exotic Ontario Lacus

The discovery of vast river systems on Titan was perhaps inevitable. Cassini has previously confirmed the presence of large masses of liquid including Ontario Lacus, a lake in the southern hemisphere composed of liquid ethane. Rainfall has also been detected in the atmosphere, hinting not of a hydrological cycle (which gives us water rain, rivers and oceans on Earth), but of a methane cycle.

It is hard not to imagine what such a river system would look like when standing next to it. But looking at this radar observation, many familiar river features such as meanders and channels can be seen.

Titan is a complex and fascinating little world laced with complex prebiotic chemistry. Apart from the Huygens probe that landed on the surface in 2005, there have been no other surface missions and plans for future missions look iffy at best.

ANALYSIS: Titan’s Hazy History and the Potential for Life

Titan might be shrouded in a cold, high pressure atmosphere that makes it difficult for our robots to explore, but it’s hard to ignore the fact that the ingredients for the basic chemistry for life is there in abundance — could there be a form of life there, perhaps taking advantage of liquid methane and ethane rather than water? We may be waiting some time to find out.
Source

January 5, 2009

TOP TEN SPACE PHOTOS: Most Viewed of 2008

10. Supernova Creates “Ribbon” in Space

Like a ribbon trailing from a parade float, a streamer of hydrogen gas seems to waft across the stars in an image taken by the Hubble Space Telescope.

Released in July, this festive shot of a supernova remnant was National Geographic News’s tenth most viewed space photo of 2008.

Bright stripes within the ribbon—which is actually the shock wave from the stellar explosion—appear where the wave is moving edge-on to Hubble’s line of sight.

Ribbon in Space (NASA)

Ribbon in Space (NASA)

9. First Picture of Alien Planet Orbiting Sunlike Star?

A faint dot above a blazing inferno is possibly the first direct view of a planet outside our solar system orbiting a sunlike star.

The infrared image, taken by the Gemini Observatory in Hawaii, was released in September. At the time astronomers weren’t sure whether the body was a planet or a planetlike object, and it remains to be seen if it is truly orbiting the star.

Two months later independent teams announced the first infrared image of an alien multiplanet system, taken using a pair of ground-based telescopes, as well as the first visible-light picture of an extrasolar planet, snapped by the Hubble Space Telescope.

First photo of alien planet orbiting a star (NASA)

First photo of alien planet orbiting a star (NASA)

Click here for Top 10 Space Photos of 2008

December 16, 2008

Enceladus has ‘spreading surface’

Filed under: Extraterrestrial Life, Inner Solar System, Moons, Saturn — bferrari @ 9:17 am
The tiger stripe fractures (bottom right) are places where the surface spreads

The tiger stripe fractures (bottom right) are places where the surface spreads

By Jonathan Amos
Science reporter, BBC News, San Francisco

A US space agency (Nasa) probe has witnessed a moon of Saturn do something very unusual and Earth-like.

Pictures of the icy satellite Enceladus suggest its surface splits and spreads apart – just like the ocean floor on our planet splits to create new crust.

The information was released at a meeting of the American Geophysical Union in San Francisco.

Evidence is mounting that liquid water lies beneath the surface

Evidence is mounting that liquid water lies beneath the surface

The data from the Cassini spacecraft is said to strengthen the idea that Enceladus harbours a sub-surface sea.

“Bit by bit, we’re accumulating the evidence that there is liquid water on Enceladus,” said Carolyn Porco, team leader of the Cassini imaging group and one of the senior scientists on the mission.

The observation on Earth that the sea floor is splitting at mid-ocean ridges and moving apart was one of the great scientific discoveries of the 20th Century; and became a key feature in the theory of plate tectonics – the idea that massive slabs of the Earth’s surface move around and are recycled.

Cassini sees something very similar on Enceladus.

The surface of this snow-white moon is riven with cracks – dubbed tiger stripes – at its south pole.

Dr Paul Helfenstein from Cornell University used digital maps of this region to reconstruct a history of the stripes, pushing the fractures around on a computer screen until they fitted together like pieces in a puzzle.

He found that sections of the cracks had clearly moved from their original locations.

Dr Helfenstein told BBC News that the resemblance to the Earth process was remarkable.

“What’s different about them is that spreading ridges on the Earth typically spread symmetrically about a rift,” he said.

“On Enceladus, what we see is a type of spreading but it is strongly asymmetric – it’s like a conveyor belt, in which, if it’s true it’s coming up from a convection well, it seems to be only pushing in one direction. It does happen on Earth, but only in very peculiar situations.”

On Earth, sea-floor spreading is fuelled by molten rock upwelling from deep inside the Earth.

On Enceladus, the scientists speculate the liquid may be water.

If that is the case, it makes this moon one of the most exciting targets for future exploration.

Enceladus is already known to have some of the fundamental chemistry required to make and sustain life. Liquid water currently is the major missing ingredient.

Dr Porco commented: “We first discovered this region in early 2005 and now it’s nearly four years later, so it’s still kind of brand new; but already there are some of us who really want to go back with a spacecraft that focuses on the south pole of Enceladus and investigates whether or not it is a site of either pre-biotic or biotic processes.”

Source: http://news.bbc.co.uk/2/hi/science/nature/7784902.stm

November 30, 2008

NASA Mission Could Find Life on Europa

Filed under: Extraterrestrial Life, Jupiter — bferrari @ 4:49 pm
Life on Europa? (NASA)

There is an ocean beneath the icy crust of Jupiter's moon Europa. Strange creatures could be swimming in these alien waters, but so far no missions have been sent there to investigate this possibility. (NASA)

By Leslie Mullen
Astrobiology Magazine
posted: 27 November 2008
09:59 am ET

Our closest view of Europa was provided by the Galileo spacecraft, which orbited the Jupiter system from 1995 to 2003. Now researchers are developing a new plan to study the moon with even greater detail. The Europa-Jupiter System Mission (EJSM) calls for one spacecraft to orbit Europa and another to orbit Ganymede, another large moon of Jupiter that also may have a liquid ocean locked beneath an icy outer layer.

EJSM would be a joint mission of NASA and the European Space Agency, with ESA in charge of the Ganymede orbiter and NASA directing the Europa orbiter. Working together, the two spacecraft also would be able to conduct limited studies of the large moons Io and Callisto, as well as the planet Jupiter.

Brad Dalton of NASA’s Jet Propulsion Laboratory, who is helping draft the EJSM proposal, says some of the instruments the Europa orbiter will carry include a camera, a spectrometer, and a powerful radar system. The radar would enable the spacecraft to peer through Europa’s ice and figure out just how thick it is.

Europa appears to have an ocean hidden under its frozen surface crust. It could be 10 times deeper than any ocean on Earth and might contain twice as much water as Earths oceans and rivers combined. (NASA)

Europa appears to have an ocean hidden under its frozen surface crust. It could be 10 times deeper than any ocean on Earth and might contain twice as much water as Earth's oceans and rivers combined. (NASA)

The Ganymede orbiter also would carry a camera and spectrometer, as well as a dust analyzer, mass spectrometer or magnetometer — instruments that could be used to study the surface composition of Ganymede and the surrounding space environment.

“The Ganymede orbiter will be more concerned with overall geophysical processes, from the interior to the magnetosphere,” says Dalton. “The Europa orbiter design is driven in part by the astrobiological significance of the Europa ocean, so it will be focused more on direct evidence for the ocean and the tidal flexing that keeps it liquid.”

Scientists have dreamed of sending a surface lander or even a submarine to investigate Europa’s ocean, but Dalton says the current vision for EJSM does not include any such instrument.

“We tried very hard, within our cost and mass constraints, to come up with a realistic lander concept,” says Dalton. “The truth is, for the amount of mass and cost it adds, it’s very difficult to include sufficient scientific capability to make it worthwhile. Part of the problem is in understanding the surface well enough to constrain the design. Once you get there, of course you are going to want to dig — and that is just outside of the current fiscal reality.”

Dalton says they considered sending a probe that would slam into the ice at high velocity. Such an impactor could provide a lot of information about the composition of the icy shell – just like the impactor did for the Deep Impact mission to a comet. The orbiter itself even could act as the impactor at the end of the mission. However, says Dalton, “this brings up some nightmarish planetary protection issues.”

“After a lot of discussion and head-scratching, it became clear that we really need to look before we leap,” says Dalton. “There is a lot we can do from orbit, (work) that needs to be done before we can send the kind of lander everybody seems to want.”

Still, Dalton says that a lander has not been absolutely ruled out. “There are some minimal instrument concepts still on the table, but nothing like a Viking or a Phoenix (lander),” he says.

One such minimal instrument could be a seismometer, in order to get a sense of how much and how frequently the ice shifts on Europa. The seismometer also could include a mass spectrometer to determine what sort of chemistry takes place within the ice.

This mission could answer the question of whether there is life on Europa by analyzing the ice shell. The underlying ocean on Europa occasionally wells up out of cracks in the ice shell and washes over the surface, erasing features like impact craters. If life is carried in these waters, then their remains could now be frozen in the ice and an orbiter could detect them.

Natural color image of Jupiters moon Europa. (NASA)

Natural color image of Jupiter's moon Europa. (NASA)

The orbiter would have a tougher time finding evidence for life if it is confined to the bottom of the ocean. Some scientists think the origin of life on Earth occurred at volcanic vents in the ocean. They suspect Europa has similar volcanic activity thanks to the gravitational influence of Jupiter, which squeezes Europa as it orbits from one side of the planet to the other. This “tidal flexing” should keep Europa’s core molten and result in volcanic activity – just look at Europa’s neighbor Io as an example. Io orbits even closer to Jupiter than Europa, and its surface is pockmarked with active volcanoes that spew sulfur and other chemical compounds into space. Many of these same compounds are found at Earth’s hydrothermal vents, and may be associated with early life on our planet.

Even if EJSM doesn’t find direct evidence for life on Europa, it may be able to determine whether the moon is generally conducive to life as we know it. If EJSM finds that Europa’s environment is habitable, says Dalton, then “that improves our prospects for searching later with a landed system.”

Of course, EJSM could determine that Europa is inhospitable to life. Yet Dalton says even if the evidence suggests Europa is a dead moon, that still won’t be the final answer about the possibility for life on Europa.

“As with Mars, where we have not yet found any evidence of life, there are still many ways life could exist there,” he notes. “EJSM will help us narrow down the possibilities so we know where to look closely. There is so much we don’t know about Europa yet.”

Arc-shaped troughs (black and white arrows) extend 100s of kilometers on the surface of Jupiters moon Europa. These enigmatic features are likely fractures resulting from a shift in Europas spin axis. Vertical scale bar (right) is 100 km. (Schenk/NASA/LPI)

Arc-shaped troughs (black and white arrows) extend 100s of kilometers on the surface of Jupiter's moon Europa. These enigmatic features are likely fractures resulting from a shift in Europa's spin axis. Vertical scale bar (right) is 100 km. (Schenk/NASA/LPI)

Several plans to send a mission to Europa have been foiled in the past. Most recently the Jupiter Icy Moons Orbiter was cancelled in 2005, partly due to the complexity of the mission plan. NASA plans to send the Juno mission to Jupiter in 2011, but that spacecraft will only orbit Jupiter and will not study any of the giant planet’s moons. ESA has been developing a Jovian Europa Orbiter, but that mission is still in the early planning stages and does not have a projected launch date yet.

NASA and ESA are currently trying to determine what the next outer planet mission will be. Competing with EJSM is TSSM, a mission to Saturn and its large moon Titan. The final selection will be made in early 2009 (the last meeting to pitch the projects was held in early November). Whichever mission is selected, the projected launch date is around 2020, with an arrival around 2030.

Source: http://wwww.space.com/businesstechnology/081127-am-europa-ejsm.html

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