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Jupiter’s moon sprays water vapors 200km into air

We just got closer to finding intelligent life – not light years away, but in our own Solar System. The revelation comes after Jupiter’s moon Europa was seen by the Hubble Space Telescope to be spurting water vapors as high as 200km into the air.

The dominant theory is currently that this is caused by water eruptions on the surface of the icy moon. But the find is more exciting yet, as it takes us one step closer to observing the possibilities for life there. Because in combination with another study, which found important minerals on the surface, scientists can begin to examine the interaction of minerals above and below the moon’s surface.

In short, all the building blocks for life are there, we just need to get close enough to understand their interaction.

The chemical vapors in the atmosphere, identified by Hubble’s sensitive filters, point to two huge plumes of water occasionally erupting on the South Pole. These eruptions are thought to eject the vapors, which reach such dazzling heights that they are seen from the moon’s orbit. This is a result of being driven by immense tidal forces, which heat up and put pressure on the moon’s vast subsurface oceans. The analysis was published December 12 in the journal Science and on the NASA website, following a meeting of the American Geophysical Union in San Francisco.

Now, the lead author of the research, Lorenz Roth of Southwest Research Institute in San Antonio, believes “If those plumes are connected with the subsurface water ocean we are confident exists under Europa’s crust, then this means that future investigations can directly investigate the chemical makeup of Europa’s potentially habitable environment without drilling through layers of ice. And that is tremendously exciting.”

Because the layer of ice could be tens of kilometers thick, this is a huge breakthrough.

Scientists see the process of chemical interaction on Europa in the following way: the vast subsurface oceans are naturally in contact with the rock below, while the ice that covers them is seen to harbor salts, producing reactions that generate heat – and this is where Jupiter comes in. Its massive gravity pull squeezes and stretches Europa so that its skin cracks and ripples, producing the water vapors and mixing up surface and sub-surface elements.

Other, parallel, findings were also revealed by NASA on Thursday and are being presented on Friday at the aforementioned meeting in San Francisco by Jim Shirley of the agency’s Jet Propulsion Lab. They reveal that new analysis from the Galileo probe (which has been exploring Jupiter and its moons since 1989) points to a ring of clay-like minerals.

These are thought to originate from Europa’s past collisions with various space rocks and give further credence to the theory that organic life-forms are indeed very likely on the moon, though no direct evidence has been found yet.

“Organic materials, which are important building blocks for life, are often found in comets and primitive asteroids,” said Jim Shirley of NASA’s Jet Propulsion Laboratory in Pasadena, California. “Finding the rocky residues of this comet crash on Europa’s surface may open up a new chapter in the story of the search for life on Europa.”

The clay-type materials seen by Shirley and team on the surface are called phyllosilicates, and were taken by Galileo back in 1998. They can be seen on a ring that is 40km wide and 120km away from the center of a crater 30km in diameter.

The theory describing collision with space rocks is explained by materials ejected from Europa at the time of impact, JPL scientists explain. The collisions probably took place at 45-degree angles, just askew enough for some of the asteroid’s minerals to stay on the surface, instead of being driven underwater.

It is still not known how the phyllosilicates from the moon’s interior could also end up on the surface – since Europa’s icy crust is about 100km thick in certain areas; however that is all the more reason to study those hard-to-reach areas and the complex chemical processes going on inside them.

At this point, scientists are still analyzing whether the massive water vapors are a direct result of the water plumes erupting on the surface, but that is so far the dominant hypothesis.

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NASA Ponders Life-Seeking Mission to Europa Moon


With tantalizing hints of a global salty ocean lying beneath a layer of fractured ice,Jupiter‘s moon Europa has been catapulted to the top of the list of suitable homes for ETs in the solar system.

Now NASA has begun mapping out what a future mission to this intriguing worldlet may look like.

new paper by leading planetary researchers released this week in the journal Astrobiologydetails plans for a possible lander being launched sometime in the next decade. The vehicle would boast a drill and microscope camera, similar to instruments aboard Mars Curiosity and Cassini (see Curiosity’s top five discoveries).

“Europa is the most likely place in our solar system beyond Earth to have life today, and a landed mission would be the best way to search for signs of life,” said Robert Pappalardo, the lead author of the study, and researcher at NASA’s Jet Propulsion Laboratory in a press statement.

Thanks to flyby robotic missions of Voyager in the 1980s and a Gallileo probe in the 1990s, Europa is thought to have a hidden ocean formed by tidal forces from nearby Jupiter’s massive gravitational effect that heats the moon’s interior. What has particularly excited researchers as potential spots to search for possible microbial life are dark, red-tainted fractures scattered across the moon’s icy shell that suggest that dirty, briny water has welled up and frozen on the moon’s surface.

NASA scientists have many questions surrounding these strange features.

What makes up the reddish “freckles” and cracks that stain the icy surface? What kind of chemistry is occurring there? Are there organic molecules, which are among the building blocks of life? (Related: “Could Jupiter Moon Harbor Fish-Size Life?”)

“Landing on the surface of Europa would be a key step in the astrobiological investigation of that world,” said Chris McKay, a senior editor of the journal Astrobiology who is based at NASA Ames Research Center in California.

“This paper outlines the science that could be done on such a lander,” said McKay. “The hope would be that surface materials, possibly near the linear crack features, include biomarkers carried up from the ocean.”

NASA’s Juno probe—which will go into orbit around the Jupiter system in 2016—will probably be tasked in helping to pin down potential landing sites for a Europa lander, thanks to its high resolution cameras.

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Europa, my main moon :) 

Europa, my main moon :)