Artist's conception of the process of terraforming Mars; the final appearance of the planet is based on data from the Mars Global Surveyor. The Mars Global Surveyor ( MGS) was a US Spacecraft developed by NASA and the Jet Propulsion Laboratory and launched

The terraforming of Mars is the hypothetical process by which the climate, surface and known properties of Mars would be deliberately changed with the goal of making it habitable by humans and other terrestrial life; and thus providing the possibility of safe and sustainable colonization of the large areas of the planet. The climate of Mars has been an issue of scientific curiosity for centuries due not least to the fact that Mars is the only terrestrial planet whose surface can be directly Planetary habitability is the measure of a Planet 's or a Natural satellite 's potential to develop and sustain Life. Mars is the focus of much speculation and serious study about possible human colonization which might be possible A planet, as defined by the International Astronomical Union (IAU is a celestial body Orbiting a Star or stellar remnant that is

Why terraform?

In the not-too distant future, population growth and demand for resources may create pressure for humans to colonize new habitats such as the surface of the Earth's oceans, the sea floor, near-Earth orbital space, the moon and nearby planets, as well as mine the solar system for energy and materials . ^[1] Thinking far into the future (in the order of hundreds of millions of years), some scientists point out that the Sun will eventually grow too hot for Earth to sustain life, even before it becomes a red giant star, because all main sequence stars brighten slowly throughout their lifetimes. The Sun (Sol is the Star at the center of the Solar System. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 A red giant is a luminous Giant star of low or intermediate mass (roughly 0 The main sequence is the name for a continuous and distinctive band of stars that appear on a plot of stellar color versus brightness When this happens, it will become imperative for humans to migrate away to areas farther from the sun if they have any hope of surviving. Through terraforming, humans could make Mars habitable long before this 'deadline'. Mars could then be in the habitable zone for a while, giving humanity some thousand additional years to develop further space technology to settle on the outer rim of the solar system, before Mars becomes uninhabitable by the sun. In Astronomy a habitable zone ( HZ) is a region of space where conditions are favorable for Life as it may be found on Earth. Space technology is Technology that is related to entering space, maintaining and using systems during Spaceflight and returning people and things The Solar System consists of the Sun and those celestial objects bound to it by Gravity.

On the other hand there are some disadvantages. If Mars were to be terraformed, significantly less sunlight would reach the surface. Sunlight, in the broad sense is the total spectrum of the Electromagnetic radiation given off by the Sun. The process of terraforming would take centuries, and the outcome is uncertain. It would produce enormous additional costs.

Background

Mars consists of much of the chemical materials needed to terraform, including abundant carbon dioxide, water (although not as much as on Earth), and oxygen, in the form of per-nitrates in the composition of the soil. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single In Inorganic chemistry, a nitrate is a salt of Nitric acid with an Ion composed of one Nitrogen and three Oxygen atoms ^[2] Due to the extremely low temperatures and pressures, a lot of carbon dioxide (CO₂) is frozen on the poles, most of the water is either frozen or in its gaseous phase, and most of the oxygen is bound to the highly oxidized metal-oxides on the Martian surface. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Altogether there are sixteen known Iron Oxides and oxyhydroxides

It is generally thought that Mars could once have had an environment relatively similar to today's Earth, during an early stage in its development. This similarity is predominantly associated with the thickness of the atmosphere and abundance of water, both considered to have been lost over the course of hundreds of millions of years. The exact mechanisms which resulted in this change are still unclear, though several mechanisms have been proposed. For instance, the gravity of Mars today indicates that lighter gases in the upper atmosphere would have contributed to this loss, with the excess atoms dissipating into space. The lack of plate tectonics on Mars today and in the past, indicated by the thorough examination of its surface features is another plausible factor, since this would cause the recycling of gases locked up in sediments back into the atmosphere to occur at a slowed rate. Plate tectonics (from Greek τέκτων tektōn "builder" or "mason" describes the large scale motions of Earth 's Lithosphere The lack of magnetic field and geologic activity may both be a result of Mars' smaller size, which allows its interior to cool more quickly than Earth's, though the details of such processes are still not precisely clear. However, none of these processes are likely to be significant over the typical lifespan of most animal species, or even on the timescale of human civilization, and the slow loss of atmosphere could possibly be counteracted with ongoing low-level artificial maintenance activities.

Changes required

Terraforming Mars would entail two major interlaced changes: building up the atmosphere and keeping it warm. The existing Martian atmosphere consists mainly of carbon dioxide, a known greenhouse gas, so once the planet begins to heat, more CO₂ enters the atmosphere from the frozen reserves on the poles, adding to the greenhouse effect. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Greenhouse gases are gaseous constituents of the atmosphere bothnatural and anthropogenic that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared This means that the two processes of building the atmosphere and heating it would augment one another, and make terraforming easier. However, on a large scale, controlled application of certain techniques (explained below) over enough time to achieve sustainable changes would be required to make theory a reality.

Building the atmosphere

Artist's conception of a terraformed Mars centered on the Tharsis region.

There are many possible techniques of building an atmosphere with the right chemical constituents to make Mars habitable, and some are easier than others to implement. If a technique is too intricate and can't sustain itself without human intervention then it should not be considered.

Chlorofluorocarbons (or CFCs) are the most likely candidates for artificial insertion into the Martian atmosphere because of their strong effect as a greenhouse gas. The haloalkanes (also known as halogenoalkanes or alkyl halides) are a group of Chemical compounds consisting of Alkanes such as Methane This can conceivably be done relatively cheaply by sending rockets with a payload of compressed CFCs on a collision course with Mars. ^[2] When the rocket crashes onto the surface it releases its payload into the atmosphere. A steady barrage of these "CFC rockets" would need to be sustained for a little more than a decade while the planet changes chemically and becomes warmer.

As the planet becomes warmer, the CO₂ on the polar caps sublimes into the atmosphere and contributes to the warming effect. The tremendous air currents generated by the moving gasses would create large, sustained dust storms, which would also contribute to the warming of the planet by directly heating (through absorbing solar radiation) the molecules in the air. Eventually Mars would be warm enough that CO₂ could not solidify on the poles, but liquid water would still not be seen because the pressure would be too low.

After the heavy dust-storms subside, the warmer planet could conceivably be habitable to some forms of terrestrial life. Certain forms of algae and bacteria that are able to live in the Antarctic would be prime candidates. Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms By filling a few of the rockets with algae spores and crashing them in the polar areas where there would still be water-ice, they could not only grow but even thrive in the no-competition, high-radiation, high CO₂ environment.

If the algae are successful in propagating themselves around parts of the planet, this would have the effect of darkening the surface and reducing the albedo of the planet. The albedo of an object is the extent to which it diffusely reflects light from the sun By absorbing more sunlight, the ground will warm the atmosphere even more, and the atmosphere will have a new small oxygen contribution from the algae. This is still not enough oxygen for humans to breathe, but it's a step in the right direction.

At first, until there is enough oxygen in the atmosphere, humans will probably need nothing more than a breathing mask and a small tank of oxygen that they carry around with them. To contribute to the oxygen content of the air, factories could be produced that reduce the metals in the soil, effectively resulting in desired crude metals and oxygen as a byproduct. Also, by bringing plants with them (along with the microbial life inherent in fertile topsoil), humans could propagate plant life on Mars, which would create a sustainable oxygen supply to the atmosphere.

Another, more intricate method, uses ammonia as a powerful greenhouse gas, and it is possible that nature has stockpiled large amounts of it in frozen form on asteroidal objects orbiting in the outer solar system, it may be possible to move these (for example, by using very large nuclear bombs to blast them in the right direction) and send them into Mars's atmosphere. Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. Since ammonia is high in nitrogen (NH₃) it might also take care of the problem of needing a buffer gas in the atmosphere. Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 A buffer gas is an inert or nonflammable Gas. In the Earth's atmosphere, Nitrogen acts as a buffer gas Sustained smaller impacts will also contribute to increases in the temperature and mass of the atmosphere.

The need for a buffer gas is a challenge that will face any potential atmosphere builders. A buffer gas is an inert or nonflammable Gas. In the Earth's atmosphere, Nitrogen acts as a buffer gas On Earth, nitrogen is the primary atmospheric component making up 77% of the atmosphere. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Mars would require a similar buffer gas component although not necessarily as much. Still, obtaining significant quantities of nitrogen, argon or some other comparatively inert gas could prove difficult. This article pertains to the chemical element For other uses see Argon (disambiguation.

Hydrogen importation could also be done for atmospheric and hydrospheric engineering. Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 A hydrosphere (from Greek ύδωρ - hydor, " Water " + σφαίρα - sphaira, " Sphere " Depending on the level of carbon dioxide in the atmosphere, importation and reaction of hydrogen would produce heat, water and graphite via the Bosch reaction. The Bosch reaction is a Chemical reaction between Carbon dioxide and Hydrogen that produces elemental Carbon ( Graphite) Water Adding water and heat to the environment will be key to making the dry, cold world suitable for Earth life. Alternatively, reacting hydrogen with the carbon dioxide atmosphere via the Sabatier reaction would yield methane and water. The Sabatier reaction or Sabatier process involves the reaction of Hydrogen with Carbon dioxide at elevated temperatures and pressures in the presence of Methane is a Chemical compound with the molecular formula. It is the simplest Alkane, and the principal component of Natural gas. The methane could be vented into the atmosphere where it would act to compound the greenhouse effect.

Artist's conception of a terraformed Mars. This realistic portrayal is approximately centered on the prime meridian and 30 degrees north latitude, and a hypothesized ocean with a sea level at approximately two kilometers below average surface elevation. The ocean submerges what are now Vastitas Borealis, Acidalia Planitia, Chryse Planitia, and Xanthe Terra; the visible landmasses are Tempe Terra at left, Aonia Terra at bottom, Terra Meridiani at lower right, and Arabia Terra at upper right. Vastitas Borealis ( Latin, 'northern waste') is the largest lowland region of Mars. Acidalia Planitia is a Plain on Mars. It is located between the Tharsis volcanic province and Arabia Terra to the north of Valles Chryse Planitia (Greek " Golden Plain " is a smooth circular plain in the northern equatorial region of Mars close to the Tharsis region to the Xanthe Terra is a large area on Mars, centered just north of the Martian equator Tempe Terra is an area in the northern hemisphere of Mars and part of the larger Tharsis region Sinus Meridiani is a feature name for an Albedo feature on Mars stretching east-west just south of that planet's Equator. Arabia Terra is a large upland region in the north of Mars. It is densely cratered and heavily eroded Rivers that feed the ocean at lower right occupy what are now Valles Marineris and Ares Vallis, while the large lake at lower right occupies what is now Aram Chaos. Valles Marineris ( Latin for Mariner Valleys, named after the Mariner 9 Mars orbiter Ares Vallis is a Valley on Mars which appears to have been carved by fluids perhaps Water. Aram Chaos, centered at 26°N 215°W is a heavily eroded Impact crater on the planet Mars.

Adding heat

Adding heat and conserving heat present is a particulary important stage of this process, as heat from the sun is the primary driver of planetary climate. Mirrors made of thin aluminized PET film could be placed in orbit around Mars to increase the total insolation it receives. Biaxially-oriented Polyethylene terephthalate (boPET Polyester film is used for its high Tensile strength, Chemical and dimensional Stability Insolation is a measure of Solar radiation energy received on a given surface area in a given time ^[3] This would direct the sunlight onto the surface and could increase the planet's surface temperature directly. The mirror could be positioned as a statite, using its effectiveness as a solar sail to orbit in a stationary position relative to Mars, near the poles, to sublimate the CO₂ and contribute to the greenhouse effect. A statite (a Portmanteau of static and satellite) is a hypothetical type of artificial Satellite that employs a Solar sail to Solar sails (also called light sails or photon sails, especially when they use Light sources other than the Sun) are a proposed form of

Since long term climate stability would be required for sustaining a human population, the use of especially powerful greenhouse gases possibly including Halocarbons such as CFCs and PFCs. The haloalkanes (also known as halogenoalkanes or alkyl halides) are a group of Chemical compounds consisting of Alkanes such as Methane Perfluorocarbons (PFCs are compounds derived from Hydrocarbons by replacement of Hydrogen Atoms by Fluorine atoms A proposal to mine fluorine-containing minerals as a source of these gases is worth noting. This proposal is supported by the belief that since the quantities present are expected to be at least as common on Mars as on Earth, this process could sustain the production of sufficient quantities of optimal greenhouse compounds (CF₃SCF₃, CF₃OCF₂OCF₃, CF₃SCF₂SCF₃, CF₃OCF₂NFCF₃) to maintain Mars at 'comfortable' temperatures, as a method of maintaining an Earth-like atmosphere produced previously by some other means. ^[4]

Changing the albedo of the Martian surface would also make more efficient use of incoming sunlight. The albedo of an object is the extent to which it diffusely reflects light from the sun ^[5] Altering the color of the surface with dark dust and soot (likely from both of Mars' moons, Phobos and Deimos, because they are dark in color and could be ground into dust while in space and then somewhat uniformly distributed across the Martian surface by "dropping" it onto Mars), dark microbial life forms or lichens would transfer a larger amount of incoming solar radiation to the surface as heat before it is reflected off into space again. Soot (ˈsʊt is a general term that refers to the black impure carbon particles resulting from the incomplete combustion of a hydrocarbon Lichens (ˈlaɪkən or /lɪtʃən/ are symbiotic associations of a Fungus (the mycobiont with a photosynthetic partner (the photobiont also known as Using life forms is particularly attractive since they could propagate themselves, once life forms exist that can survive and be metabolically active on Mars.

Another way to increase the temperature is to smash small cosmic bodies (asteroids) onto the Martian surface. The impact energy is released as heat and could evaporate Martian water ice to steam, which too is a greenhouse gas.

Dealing with radiation

It is believed by some that Mars would be uninhabitable to most life-forms due to higher radiation levels. Without a magnetosphere, the sun is thought to have thinned the Martian atmosphere to its current state; the solar wind adding a significant amount of heat to the atmosphere's top layers which enables the atmospheric particles to reach escape velocity and leave Mars (effectively boiling off the atmosphere). The solar wind is a Stream of charged particles&mdasha plasma &mdashthat are ejected from the upper atmosphere of the Sun. In Physics, escape velocity is the speed where the Kinetic energy of an object is equal to the magnitude of its Gravitational potential energy Indeed, this effect has even been detected by Mars-orbiting probes. Venus, however, shows that the lack of a magnetosphere does not preclude a dense atmosphere. The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University A thick atmosphere will also provide radiation protection for the surface, as it does at Earth's polar regions where aurorae form, so the lack of a magnetosphere would not seriously impact the habitability of a terraformed Mars. In the past, Earth has regularly had periods where the magnetosphere changed direction and collapsed for some time. Some scientists believe that in the ionosphere a magnetic shielding was created almost instantly after the magnetosphere collapsed, a principle that applies to Venus as well and would also be the case in every other planet or moon with a large enough atmosphere. The ionosphere is the uppermost part of the atmosphere, distinguished because it is Ionized by solar radiation The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University

See also

• Colonization of Mars
• Terraforming of Venus
• Total Recall, an American science fiction film from 1990; an example of popular culture speculation regarding the terraforming of Mars. Mars is the focus of much speculation and serious study about possible human colonization which might be possible Terraforming of Venus is the (theoretical process of engineering the global environment of the planet Venus in such a way as to make it suitable for human habitation Total Recall is a 1990 Academy Award -winning American Science fiction film.
• Mars trilogy, a science fiction trilogy of novels by Kim Stanley Robinson which goes into great depth about possible terraforming techniques and the consequences resulting. Kim Stanley Robinson (born March 23 1952) is an American Science fiction Writer, probably best known for his award-winning

References

External links

• Recent Arthur C Clarke interview mentions terraforming
• Red Colony
• Terraformers Society of Canada
• Research Paper: Technological Requirements for Terraforming Mars
• Peter Ahrens The Terraformation of Worlds
• MARSDRIVE: Colonizing Mars. Red Colony parent organization planning the future exploration and colonization of planet mars.
• Mars Reborn, a portrait of a possible Mars one thousand years from now, by Chris Wayan, 2003