Europa is a moon of the planet Jupiter. It is the sixth moon in position by length of orbital period and the fourth largest by diameter and mass of Jupiter's satellites. It was discovered in 1610 by Galileo Galilei and is the smallest of the four Galilean moons named in his honour
Europa is somewhat similar in bulk composition to the terrestrial planets, being primarily composed of silicate rock. It has an outer layer of water thought to be around 100 km thick (some as frozen ice upper crust, some as liquid ocean underneath the ice), and recent magnetic field data from the Galileo orbiter shows that Europa generates an induced magnetic field by interacting with Jupiter's field, which suggests the presence of a subsurface conductive layer which is likely a salty liquid-water ocean. Europa probably also contains a metallic iron core.
Surface
The Europan surface is relatively smooth; few features more than a few hundred meters high have been observed, but topographic relief in places approaches a kilometer (1/2 mile). Europa is the smoothest object in the solar system. The prominent markings crisscrossing the moon seem to be mainly albedo features, which emphasize low topography. There are very few craters on Europa, and its albedo is one of the highest of all moons. This would seem to indicate a young and active surface; based on estimates of the frequency of cometary bombardment that Europa probably endures, the surface is about 20 to 180 million years old [3] (the geological features of the surface clearly show a variety of ages).
It is thought that under the surface there is a layer of liquid water kept warm by tidally generated heat. The temperature on the surface of Europa averages about 110 K (-163.15 °C) at the equator and only 50 K (-223.15 °C) at the poles, and so the surface water ice is permanently frozen. The first hints of a subsurface ocean came from theoretical considerations of the tidal heating (a consequence of Europa's slightly eccentric orbit). In a recent book[4], Galileo imaging team member Richard Greenberg uses his research group's analyses of Voyager and Galileo images of Europa to argue that Europa's geological features also demonstrate the existence of a subsurface ocean. The most dramatic example being "chaos," a common feature on Europa's surface that Greenberg interprets as a region where the subsurface ocean melted through the icy crust. This interpretation is extremely controversial. Most geologists who have studied Europa favor what Greenberg calls the "thick ice" model, in which the ocean has rarely, if ever, directly interacted with the surface[5]. Greenberg and his group argue that the ice is less than 10 km thick, and probably much thinner, as thin as 2 km.
The best evidence for the so called "thick ice" model is a study of Europa's large craters. The largest craters are surrounded by concentric rings and appear to be filled with relatively flat, fresh ice; based on this and on the calculated amount of heat generated by Europan tides it is predicted that the outer crust of solid ice is approximately 10-30 kilometres (5-20 miles) thick, which could mean that the liquid ocean underneath may be about 100 km (60-65 miles) deep[3].
Approximately natural color image of Europa by the Galileo spacecraftEuropa's most striking surface feature is a series of dark streaks criss-crossing the entire globe. Close examination shows that the edges of Europa's crust on either side of the cracks have moved relative to each other. The larger bands are roughly 20 km (12 miles) across commonly with dark diffuse outer edges, regular striations, and a central band of lighter material. These may have been produced by a series of volcanic water eruptions or geysers as the Europan crust spread open to expose warmer layers beneath. The effect is similar to that seen in the Earth's oceanic ridges. These various fractures are thought to have been caused in large part by the tidal stresses exerted by Jupiter; Europa's surface is thought to rise and fall up to 30 meters (nearly 100 feet) between high and low tides. Since Europa is tidally locked to Jupiter, and therefore always maintains the same orientation towards the planet, the stress patterns should form a distinctive and predictable pattern. However, only the youngest of Europa's fractures conform to the predicted pattern; other fractures appear to have occurred at increasingly different orientations the older they are. This can be explained if Europa's surface rotates slightly faster than its interior, an effect which is possible due to the subsurface ocean mechanically decoupling the moon's surface from its rocky mantle and to the effects of Jupiter's gravity tugging on the moon's outer ice crust. Comparisons of Voyager and Galileo spacecraft photos suggest that Europa's crust rotates no faster than once every 10,000 years relative to its interior.
Craggy mountains and smooth plates jumbled together in the Conamara Chaos regionAnother type of feature present on Europa are circular and elliptical lenticulae, Latin for "freckles". Many are domes, some are pits and some are smooth dark spots. Others have a jumbled or rough texture. The dome tops look like pieces of the older plains around them, suggesting that the domes formed when the plains were pushed up from below. It is thought that these lenticulae were formed by diapirs of warm ice rising up through the colder ice of the outer crust, much like magma chambers in the Earth's crust. The smooth dark spots could be formed by meltwater released when the warm ice breaks the surface, and the rough, jumbled lenticulae (called regions of "chaos", for example the Conamara Chaos) appear to be formed from many small fragments of crust embedded in hummocky dark material, perhaps like icebergs in a frozen sea.
Atmosphere
In 1994, observations with the Goddard High Resolution Spectrograph of the Hubble Space Telescope revealed that Europa has a very tenuous atmosphere (1 micropascal surface pressure) composed of oxygen.[6] Of all the moons in the solar system only six others (Io, Callisto, Enceladus, Ganymede, Titan and Triton) are known to have atmospheres. Unlike the oxygen in Earth's atmosphere, Europa's is not of biologic origin. It is most likely generated by sunlight and charged particles hitting Europa's icy surface producing water vapor which is subsequently split into hydrogen and oxygen. The hydrogen escapes Europa's gravity due to its low atomic mass, leaving the oxygen behind.
Subsurface ocean
The Galileo orbiter has found that Europa has a weak magnetic field (about one quarter the strength of the Ganymedean field and similar to Callisto's) which varies periodically as Europa passes through Jupiter's massive magnetic field. A likely explanation of this is that there is a large, subsurface ocean of liquid salt water.[7] Spectrographic evidence suggests that the dark reddish streaks and features on Europa's surface may be rich in salts such as magnesium sulfate (Epsom salt), deposited by evaporating water that emerged from within. Sulfuric acid hydrate is another possible explanation for the contaminant observed spectroscopically. In either case, since these materials are colorless or white when pure, some other material must also be present to account for the reddish color. Sulfur compounds are suspected.
It has been suggested that life may exist in this under-ice ocean, perhaps subsisting in an environment similar to Earth's deep-ocean hydrothermal vents or the Antarctic Lake Vostok. There is currently no observational evidence for this hypothesis, but efforts have nevertheless been made to avoid any possibility of contamination. The Galileo mission was concluded in September 2003 by crashing the spacecraft into Jupiter — if simply abandoned, the unsterilized craft might have eventually crashed into Europa and contaminated it with terrestrial microorganisms. The introduction of such microorganisms could make it impossible to determine if Europa ever had its own native life, or could even destroy such life if it exists.
Exploration of Europa
Artist's concept of the cryobot and hydrobotMost of our knowledge of Europa comes from the flybys by the Voyager and Galileo missions. Various proposals have been made for future missions. The extremely ambitious Jupiter Icy Moons Orbiter was canceled in 2005.[8]
The 2006 NASA budget includes Congressional language imploring NASA to fund a mission that would orbit Europa. Such a mission would be able to confirm a subsurface ocean using gravity and altimetry measurements, elucidate the origin of surface features by imaging much of the surface at high resolution, constrain the chemistry of surface materials using spectroscopy, and probe for subsurface liquid water using ice-penetrating radar. The mission might even carry a small lander to determine the surface chemistry directly, and to measure seismic waves, from which the level of activity and ice thickness could be determined. However, at present it is far from certain that NASA will actually fund this mission, as funding for it is not included in NASA's 2007 budget plan.
More ambitious ideas have been put forward for a capable lander to test for evidence of life that might be frozen in the shallow subsurface, or even to directly explore the possible ocean beneath Europa's ice. One proposal calls for a large nuclear powered "Melt Probe" (cryobot) which would melt through the ice until it hit the ocean below. Once it reached the water, it would deploy an autonomous underwater vehicle (hydrobot), which would gather information and send it back to Earth. Both the cryobot and the hydrobot would undergo some form of extreme sterilization to negate the chance of contamination to any possible ecosystem on Europa. This proposed mission has not yet reached a serious planning stage.
2006-07-16 02:42:34
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answer #1
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answered by Anonymous
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Jupiter is a gas giant planet and has no solid surface. It is much larger than the Earth and its gravity it very strong. If there were a solid surface, a person would be crushed by it. The atmosphere would be very toxic as well, consisting of mainly methane and ammonia. The radiation that exist at Jupiter would be enough to kill any life form with seconds without any heavy radiation shielding.
As for the great red spot, it is even big enough to swallow the whole Earth. It is a huge anticyclonic storm in Jupiter's atmosphere that has existed for centuries, an a new was was recently discovered (Red Spot Jr.) and these two storms are now passing each other.
Not sure where you are getting your information from, but it has more holes in it than Swiss cheese. Just remember to take you medication a do what the nice doctors tell you to do.
2006-07-16 02:04:23
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answer #2
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answered by Shaula 7
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I think you smoked up before you did all that writing, Jupiter is a GAS giant. ie it caontains NO surface, the gases just get denser and denser as you go into the inner cores, I think you meant the Moons that orbit Jupiter, ie its natural satelites. Jupiter is 90% hydrogen and 10% helium, and Jupiter's crust isn't "frangible". Jupiter though will have a rocky innermost core due to the pressure and gravitational collapse. The moons Io, Europa, Ganymede, Callista are the larger moons are where we might get some joy if we are to settle down out there, but once again that's a long shot. There isn't going to be any inter-planetary travelling for a long time to come, a hundred years is too short a time frame, our exploratory expenditures for the coming years is going to drasticallly decrease, and I think technology wise we might come to a stand still. The method you have described doesn't actually seem plausible but it could happen.
2006-07-16 06:46:37
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answer #3
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answered by Gooner44 2
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I really dought people will be living on jupiter in the next thousaaand years because jupiter is a massive gass giant with super storms! So many times has nasa tried getting things to land but the super storms and emence radiation would tear your skin off in aa trillionth of a second. So no I believe after jupiter has imploded to a tenth of its own size we might be able to grasp it's true potential.
Jupiter has a lot of moons at which scientists have been looking at for a couple of years now they seem like a more than likely place to explore let alone think about living on it.
2006-07-25 05:11:22
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answer #4
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answered by joe p 1
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Jupiter? With gravity so strong that a human would be squashed like a bug? I don't think so. > Although it is a bit smaller than our earth. Actually, Jupiter is about ten times LARGER in diameter than out Earth, a thousand times larger in volume. > very abundant water ice and mineral substance No water ice and any mineral are buried thousands of kilometres deep in a toxic atmosphere. > the secondary planet of the Jupiter. Wait a minute...are you talking about a MOON of Jupiter? Why are you calling it a PLANET? > the Jupiter crust is rather frangibility Jupiter doesn't have a crust, because it doesn't have a solid surface. > the Great Red Spot always exist and it’s position’s immovability is one of the attestation The Great Red Spot is NOT immovable: it actually drifts back and forth in longitude. It is clearly an atmospheric phenomenon. > the liquid hydrogen which on the Jupiter’ surface Jupiter has no surface and no liquid hydrogen. > under the the Great Red Spot is the alp on the continent Impossible, since the Great Red Spot drifts back and forth in longitude. By the way an "alp" is a valley, not a mountain.
2016-03-16 07:18:00
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answer #5
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answered by Anonymous
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Perhaps you're referring to the moons of Jupiter? Of the inner moons, Amalthea, Europa, Io, Ganymede and Callisto, Ganymede has the necessary elements for human survival and Io probably has water, so theoretically they could be terraformed one day, but all these moons are within the Van Allen belts of Jupiter which means they are exposed to cosmic radiation that humans can't withstand.
If you're referring to the planet Mars, we may indeed colonize it one day. With the way the world spends it's resources on wars, it will be far longer than 100 years before we get there.
2006-07-28 09:00:16
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answer #6
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answered by nursesr4evr 7
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YO, i just wanna tell man, jupiter is larger than earth but not bit smaller.
Don't even think to live up their, we can't even imagine even after 1000 years because it is all made up of gases like hydrogen, helium and methane which are very harmful for us.
Jupiter's surface is not solid it is liqiuid a person will sink down and a boat will burn up. the essential things like water and oxygen have no clue up there.
So, forget to have a lifespan at jupiter.
2006-07-16 01:51:28
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answer #7
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answered by DESI BOY! 2
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I was under the impressions that Jupiter was a gaseous planet, not SOLID mass like earth, and its atmosphere is inhabitable by humans.
Our better bet would be space stations, or even mars, as it is a solid planet and so far, closest in matter to earth.
I could be wrong, but I doubt that we will ever live on Jupiter. But happily, I won't be around in 100 years to find out.
2006-07-16 01:49:13
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answer #8
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answered by Anonymous
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Possilbly... But maybe longer than 100 years?? If people start conserving Earth's natural resources so that they do not deplete at a rate faster than the rate of replacement, there is still hope for survival on Earth.. Afterall, Earth is still the best place to live in..
Or maybe humans would have evolved to adapt to the changing Earth so there might be no need to move to another planet afterall..
2006-07-16 01:48:43
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answer #9
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answered by Forest_aude 3
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Jupiter's gravity is almost 2 1/2 times stronger that earth. A 150 pound person would weigh almost 375 pounds. Our muscles and hearts couldn't take it for extended periods of time. But, there wouldn't be many fat people that's for sure.
2006-07-26 21:11:44
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answer #10
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answered by keep_up_w_this 4
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Maybe one of it's moons but not the planet it self. It is a gas giant with little or no surface and it would take 1000 earths just to fill it up. I do believe that one day man will have colony's on other planets possable Mars or our moon.
2006-07-16 01:53:04
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answer #11
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answered by jerryhmusic 3
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