How Do We Terraform Jupiter’s Moons?

The primeval vegetation of Europe began to take shape as the climate ameliorated following the retreat of the Pleistocene ice sheets some 12, years ago. Sufficient enough to limit the effects of muscle and bone degeneration, this lower gravity also means that the moon has a lower escape velocity — which means it would take considerably less fuel for rockets to take off from the surface. You may find it helpful to search within the site to see how similar or related subjects are covered.

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Unai Emery gave the kids a chance vs. Vorskla and they didn't disappoint: To put that into perspective, it took the Voyager probes between 18 months and two years to reach Jupiter from Earth.

Ships designed to haul human passengers with enough supplies and equipment to sustain them would be much larger and heavier, which would make the travel time even longer.

And since missions to this region of space would need to haul back several tons of icy cargo, they too would need powerful propulsion systems to make the journey in a reasonable amount of time. Ergo, any vessels transporting human crews to the Jovian system would likely have to rely on cryogenics or hibernation-related technology in order to be smaller, faster and more cost-effective.

While this sort of technology is being investigated for crewed missions to Mars , it is still very much in the research and development phase. As for transport missions to and from the Asteroid Belt, these could be equipped with systems like Nuclear-Thermal Propulsion NTP , Fusion-drive systems , or some other advanced concept. But thus far, no such drive systems exist, with some being decades or more away from feasibility. Also, all this talk of transport and space hauling brings up the second aspect of this challenge, which is the problem of infrastructure.

In order to mount multiple crewed missions to the Jovian system, as well as asteroid retrieval missions, a considerable amount of infrastructure would be needed that either does not exist or is severely lacking. This includes having lots of spaceships, which would also need advanced propulsion systems. Just as important is the need for refueling and supply stations between Earth and the Jovian System — like an outpost on the Moon, a permanent base on Mars, and bases on Ceres and in the Asteroid Belt.

While these could be harvested from the nearby Asteroid Belt, it would require thousands of ships and robot workers to mine, haul, and assemble the minerals into large enough shells. Third, radiation would be a significant issue for humans living on Europa or Ganymede. As noted already, Earth organisms are exposed to an average of 24 rem per year, which works out to 0. Of all the Galileans, only Callisto falls beneath this terminal limit.

As a result, any settlements established on Europa or Ganymede would require radiation shielding, even after the creation of viable atmospheres. This in turn would require large shields to be built in orbit of the moons requiring another massive investment in resources , or would dictate that all settlements built on the surfaces include heavy radiation shielding.

On top of that, as the surfaces of Europa, Ganymede and Callisto especially Callisto! These satellites are lost on a regular basis, and new ones are added all the time. So colonists would naturally have to worry about space rocks slamming into their ocean world, causing massive waves and blotting out the sky with thick clouds of water vapor.

In order to maintain the effects of terraforming, colonists would need to replenish the atmosphere over time.

Another aspect of sustainability, one which is often overlooked, has to do with the kinds of planets that would result from terraforming. While estimates vary, transforming Europa, Ganymede and Callisto would result in oceans that varied in depth — from km in the cae of Europa to extreme depths of up to km in the case of Ganymede. With oceans this deep, all settlements would have to take the form of floating cities that could not be anchored to solid ground.

And in the case of Ganymede, the oceans would account for a considerable portion of the planet. What the physicals effects of this would be are hard to imagine. But it is a safe bet that they would result in tremendously high tides at best to water being lost to space. And finally, there is the issue of the ethics of terraforming.

If, as scientists currently suspect, there is in fact indigenous life on one or more of the Jovian moons, then the effects of terraforming could have severe consequences or them. Life forms that exist close to the core-mantle boundary, most likely around hydrothermal vents, would be less effected by the presence of humans on the surface. However, any changes to the ec0logical balance could lead to a chain reaction that would destroy the natural life cycle.

And the presence of organisms introduced by humans i. So basically, if we choose to alter the natural environment of one or more of the Jovian moons, we will effectively be risking the annihilation of any indigenous life forms. Such an act would be tantamount to genocide or xenocide, as the case may be , and exposure to alien organisms would surely pose health risks for human colonists as well.

All in all, it appears that terraforming the outer Solar System might be a bit of a non-starter. While the prospect of doing it is certainly exciting, and presents many interesting opportunities, the challenges involved do seem to add up. Third, a terraformed Europa, Ganymede and Callisto would all be water worlds with extremely deep oceans. Would it even be possible to build floating cities on such a world?

And last, but not least, any act of terraforming these moons would invariably threaten any life that already exists there. Under all of these circumstances, would it not be better to simply establish outposts on the surface, or perhaps within or directly underneath the ice?

All valid questions, and ones which we will no doubt begin to explore once we start mounting research missions to Europa and the other Jovian moons in the future.

And depending on what we find there, we might just choose to put down some roots. And in time, we might even begin thinking about renovating the places so more of our kin can drop by. The northern vegetation may superficially suggest its primeval character, but the zone of mixed forest that once stretched across the continent from Great Britain and Ireland to central Russia has been changed extensively by humans. Surviving patches of woodland—associations of broad-leaved trees and some conifers, summarily described as Atlantic, central, and eastern—hint at the formerly extensive cover.

In southern Europe, Mediterranean vegetation has a distinctive character, containing broad-leaved evergreen trees and shrubs as well as areas of scrub. Around the sea that vegetation is called maquis ; it includes aromatic plants and small trees such as olives and figs. Scrub is scattered because of summer drought, particularly in areas where the soil is underlain by limestone or where there is little, if any, soil.

The wooded-steppe and grass-steppe vegetation zones are confined primarily to southwestern Russia and Ukraine, although they also extend into the Danubian lowlands see the Steppe. Semidesert vegetation characterizes the dry lowland around the northern and northwestern shores of the Caspian Sea.

The primeval vegetation of Europe began to take shape as the climate ameliorated following the retreat of the Pleistocene ice sheets some 12, years ago. The microscopic study of pollen grains preserved in datable layers of peat and sediments has made it possible to trace the continental spread, in response to climatic improvement, of forest-forming trees.

The double barrier of the Alps and the Mediterranean Sea had checked the southward retreat of trees at the onset of the ice ages , and there were relatively few indigenous species to return northward from unglaciated refuges.

In the first postglacial climatic phase the Boreal , spruce , fir, pine , birch, and hazel nevertheless established themselves as far north as central Sweden and Finland. During the succeeding climatic optimum the Atlantic phase , which was probably wetter and certainly somewhat warmer, mixed forests of oak , elm, common lime linden , and elder spread northward.

Only in the late Atlantic period did the beech and hornbeam spread into western and central Europe from the southeast.

During postglacial times, therefore, when small numbers of humans were living within Europe, the continental surface was thickly clad with trees and undergrowth, except where tree growth was precluded by extreme cold, high elevation, bad drainage, or exposure to persistent gales.

Even those areas where windblown loess was deeply deposited are now known to have had woods of beech, hawthorn, juniper, box, and ash, as did limestone plateaus. The Mediterranean peninsulas also had evergreen and mixed forests rooted in an ample soil. From prehistoric times onward, with ever-increasing force, humans, seeking optimum economic use of available resources, have acted as a vigorous agent of vegetation change.

The effects of grazing animals may well explain why some heathlands e. By fire and later by ax, forest clearance met demands for building materials for homes and ships, for fuel, for charcoal for iron smelting, and, not least, for more available land for cultivation and pasture. The mixed forests suffered most because their relatively rich soils and long and warm growing season promised good returns from cultivation.

The destruction of woodlands was markedly strong when population was growing as between about and ce. It was later intensified by German colonization east of the Rhine and reached maximum scale in the 19th century.

In southern Europe—where naval demands were continuous and sources of suitable timber sharply localized—tree cutting entailed, from Classical antiquity onward, serious soil loss through erosion, increased aridity, floods, and marsh formation. Farther north throughout the continent, as present distribution of arable land shows, forests were reduced to remnants; only in the north and below the snow line of Alpine mountains have forests of large and continuing commercial value survived.

Another drastic vegetation change brought about by humans has been the virtual elimination of the wooded and grass steppes, which have become vast granaries. On the more positive side may be noted the reclamation of marshlands and the improvement of the soil, through agriculture, of some hill grasslands and heaths.

In timber-deficient countries the afforestation of hillslopes, chiefly with quickly growing conifers, has restored some of the former forests. Second-growth forests also have come to occupy some areas where poor agricultural land has been abandoned. Humans have not only shaped the vegetation zones of Europe. They also have introduced many of the individual species of plants, both wild and cultivated , that commonly grow on the continent.

To a perhaps surprising degree, European vegetation comprises a large number of plants originally from other parts of the world. Although some imported crops—notably citrus fruits, sugarcane, and rice—can grow only marginally in Europe, and then by irrigation, many others thrive throughout the continent.

Originating as wild grasses in Ethiopia, cultivated varieties of wheat and barley reached Europe early, via the Middle East and Egypt, as did the olive , the grape, figs, flax, and some varieties of vegetables. Rice, sugarcane, and cotton, of tropical Indian origin, were introduced by the Arabs and Moors, especially into Spain.

Citrus fruits, peaches, mulberries, oats, and millet reached Europe from their original Chinese habitats, and Europe owes corn maize , tobacco, squashes, tomatoes, red peppers, prickly pears, agave sisal , and potatoes—first grown for fodder but destined to become the cheap staple food for the large families of low-paid workers of the 19th century—to the Americas. Europe has drawn greatly on East Asia and North America for trees, especially ornamental trees, while some acacias and the eucalyptus derive from Australia.

The commercially important sugar beet , however, was developed in Europe in the 18th century; its cultivation increased greatly in the following century, particularly after the British blocked the importation of cane sugar during the Napoleonic Wars. With animals as with plants, the earlier Pleistocene range and variety has been much reduced by the expansion of human settlement. Wild fauna has been long in retreat since Upper Paleolithic times beginning about 40, years ago , when, as cave drawings portray, small human groups held their own against such big game as aurochs and mammoths , now extinct, and also against such survivors as bison, horses, and boars.

Hares, swans, and geese were also hunted, and salmon, trout, and pike were fished. Humans were, inevitably, the successful competitor for land use. By prolonged effort, settlers won the land for crops and for domesticated animals, and they hunted animals, especially for furs.

As population mounted in industrializing Europe, humans no less inevitably destroyed, or changed drastically, the wild vegetation cover and the animal life. With difficulty, and largely on human sufferance, animals have nevertheless survived in association with contemporary vegetation zones.

In the tundra some reindeer caribou , both wild and domesticated, are well equipped to withstand the cold. Their spoon-shaped hooves are useful for finding food in rough ground. Their herds migrate southward in winter and eat lichens and plants as well as flesh, notably that of lemmings and voles.

Arctic foxes, bears, ermines, partridge, and snowy owls may appear in the tundra, where, in the short summer, seabirds, river fish, and migrant birds swans, ducks, and snipes vitalize a harsh environment, then made almost intolerable by swarms of biting midges. In the boreal forests the richness of animal and bird life, which had persisted throughout much of historical times, now has been greatly reduced.

Among large surviving mammals are elks moose , reindeer, roe deer , and brown bears. Lynx have been exterminated, but not wolves, foxes, martens, badgers, polecats, and white weasels. Sables , which are much hunted for their valuable fur, only just survive in the northeastern forests of European Russia. Rodents in the forests include squirrels, white Arctic hares, and in the mixed forests gray hares and beavers. Among birds are black grouse, snipes, hazel hens, white partridge, woodpeckers, and crossbills, all of which assume protective colouring and are specially adapted to be able to find their food in a woodland environment.

Owls, blackbirds, tomtits, and bullfinches may be seen in the forests and geese, ducks, and lapwings in meadow areas. In Mediterranean Europe, remnants of mountain woodland harbour wild goats, wild sheep—such as the small mouflon of Corsica and Sardinia—wildcats, and wild boars.

Snakes, including vipers, and lizards and turtles are familiar reptiles, but birds are few. The steppe zones now lack large animals, and the saiga a hoofed mammal of the family Bovidae has disappeared. Numerous rodents, including marmots, jerboas, hamsters, and field mice, have increased in numbers to become pests, now that nearly all the steppes are under cultivation. Equally plentiful birds include bustards—which can fly as well as run—quail, gray partridge, and larks.

Many take on yellowish gray or brown protective colouring to match the dried-up grass. Eagles, falcons, hawks, and kites are the birds of prey; water and marsh birds—especially cranes, bitterns, and herons—also make their homes in the steppes. Different kinds of grasshoppers and beetles are insect pests. The animals of the semidesert areas to the north and northwest of the Caspian Sea also show affiliations with the fauna of the grass steppe and the desert between which they live.

Saigas survive there, as do rodent sand marmots and desert jerboas and, as beasts of prey, sand badgers. There are many reptiles—lizards, snakes cobras and steppe boas , and tortoises.

Livestock are selectively bred and raised with some regard to the physical character of their environment as well as to market demands and government decisions. In the far north, herds of reindeer provide meat, milk, pelts, wool, and bone to the Sami people. In the rough hilly scrubland of Mediterranean Europe, sheep, goats, donkeys, mules, and asses are common. The horse , which in its long history has drawn chariots, carried mounted knights, and hauled plows, wagons, artillery, stagecoaches, canal boats, and urban trams, is now raised more for racing, riding, ceremonial uses, and the hunting of fox and stag but is still used for farm work, especially in eastern Europe.

Distribution maps of animals kept on farms show how widely they enter into agriculture: The European environment, once not so unequally shared by animals and people, has, with the march of civilization, been subjected to human attempts. Land development, hunting for sport or to protect crops, the pollution of seas and fresh waters, and the contamination of cropland have reduced many animal species, though strong efforts have been made to preserve those threatened with extinction, in such refuges where they still live.

Seabirds find safe homes, for example, in the Lofoten Islands of Norway and the Farne Islands of northeastern England. The snowy owl , which feeds on lemmings, is seen in Lapland , the rare great bustard in the Austrian Burgenland , and the musk ox in Svalbard. In Poland and Belarus, national parks within the Belovezhskaya Forest contain deer, wild boars, elks moose , bears, lynx, wolves, eagle owls, black storks, and European bison wisents.

Golden eagles, Alpine marmots, and chamois are to be seen in the Bavarian Alps near Berchtesgaden , Germany. The beautiful wild horses of the Camargue nature reserve France , the wild ponies of the New Forest England , and the Barbary macaques Gibraltar continue undiminished in popular interest. We welcome suggested improvements to any of our articles. You can make it easier for us to review and, hopefully, publish your contribution by keeping a few points in mind.

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