The problem of energy accessibility and production on Mars is one of
the three main challenges for the upcoming colonisation of the red
planet. The energetic potential on its turn is mainly dependent on the astrophysical characteristics of
the planet. A short insight into the Mars environment is thus the
compulsory introduction to the problem of energy on Mars.
The present knowledge of the Martian environment is the result of more than two centuries of attentive observation on
its astronomical appearance and, more recently, on its on-site
astrophysical features. Recent surface measurements of Martian geology,
meteorology and climate had fixed the sometime-unexpected image of a
completely desert planet.
Mars is one of the most visible of the
seven planets within the solar system and thus for its discovery cannot
be dated, still the interest for Mars is old. It was easily observed
from the ancient times by necked eye and the peculiar reddish glance of
the planet had induced the common connection of the poor planet with the
concept of war. The god of war and the planet that inherited his name
had provoked, still from antiquity, curiosity and disputes on the most
diverse themes. These disputes are at a maximum right now regarding the
habitability of Mars.
The red planet owes his color to still
unexplained causes, where a yet undisclosed chemistry of iron oxides
seems to be the main actor. The visit card of Mars is fast increasing in
the quantity of data and is now quite well known (Bizony, 1998), as we
observe from the description that follows.
Mars as seen before the space age
As
far as the knowledge of the solar system has gradually extended, from
optical, ground-based observations to the present astrophysical research
on site, Mars appears as the fourth planet as starting from the Sun.
The reddish planet of the skies, nicely visible by necked eyes, has
attracted the most numerous comments during the time regarding the
presence of life on an extra terrestrial planet.
With all other
eight planets, except for Pluto-Charondoublet, Mars aligns to a strange
rule by orbiting the Sun at a distance that approximates amultiple of √2
from that of the Earth. This means that the rough 149.6 mil km of the
Earth semi-major axis is followed by a rough 212 mil km for Mars. In
fact there are 227.92 mil km at mean from the center of Sun. The power
rule of Titius-Bode, modified several times, but originally described
as a = (4 + 3 x sgn n x 2n-1) / 10 | n = 0,9 gives a better distribution.
Table 1. Mars within Titius-Bode’s rule (astronomical units)
Planet | n | Titius-Bode rule | Actual semi-major axis |
Mercury | 0 | 0.4 | 0.39 |
Venus | 1 | 0.7 | 0.72 |
Earth | 2 | 1.0 | 1.00 |
Mars | 3 | 1.6 | 1.52 |
Asteroids | 4 | 2.8 | 2.80 |
Jupiter | 5 | 5.2 | 5.20 |
Saturn | 6 | 10.0 | 9.54 |
Uranus | 7 | 19.6 | 19.20 |
Neptune/Pluto | 8 | 38.8 | 30.10/39.20 |
Sedna | 9 | 77.2 | 75.00 |
It
is immediately seen that the primary solar radiation flux is roughly
two times smaller for Mars than it is for Earth. More precisely, this
ratio is equal to 2.32. This observation for long has
suggested that the climate on Mars is much colder than the one on Earth.
This has not removed however the belief that the red planet could be
inhabited by a superior civilization. Nevertheless, beginning with some
over-optimistic allegations of Nicolas Camille Flammarion (Flamarion,
1862) and other disciples of the 19-th century, the planet Mars was for a
century considered as presenting a sort of life, at least microbial if
not superior at all. The rumor of Mars channels is still impressing
human imagination.
When estimates begun to appear regarding the
Martian atmosphere and figures like 50 mbar or 20 mbar for the air
pressure on Martian ground were advanced (Jones 2008), a reluctant wave
of disapproval has been produced. It was like everybody was hoping that
Mars is a habitable planet, that we have brothers on other celestial
bodies and the human kind is no more alone in the Universe. As more data
were accumulating from spectroscopic observations, any line of emission
or absorption on Mars surface was immediately related to possible
existence of biological effects.
Even during the middle 20-th century the same manner was still preserving. In their book on “Life in the Universe”
Oparin and Fesenkov are describing Mars in 1956 as still a potential
place for biological manifestations (Oparin & Fesenkov, 1956).The
following two excerpts from that book are relevant, regarding the
claimed channels andbiological life on Mars: “…up to present no
unanimous opinion about their nature is formed, although nobody
questions that they represent real formations on the planet (Mars)…” and
at the end of the book “On Mars, the necessary conditions for the
appearance and the development of life were always harsher than on
Earth. It is out of question that on thisplanet no type of superior form
of vegetal or animal life could exist.
However, it is possiblefor life, in inferior forms, to exist there, although it does not manifest at a cosmic scale.
Reasons and costs for terraforming Mars
Thicken
Mars’ atmosphere, and make it more like Earth’s. Earth’s atmosphere is
about 78% Nitrogen and 21% Oxygen, and is about 140 times thicker than
Mars’ atmosphere. Since Mars is so much smaller than Earth (about 53% of
the Earth’s radius), all we’d have to do is bring about 20% of the
Earth’s atmosphere over to Mars. If we did that, not only would Earth be
relatively unaffected, but the Martian atmosphere, although it would be
thin (since the force ofgravity on Mars is only about 40% of what it is
on Earth), would be breathable, and about the equivalent consistency of
breathing the air in Santa Fe, NM.
So that’s nice; breathing is
good. Mars needs to be heated up, by a lot, to support Earth-like life.
Mars is cold. Mars is damned cold. At night, in the winter, temperatures
on Mars get down to about -160 degrees! (If you ask, “Celcius or
Fahrenheit?”, the answer is first one, then the other.) But there’s an
easy fix for this: add greenhouse gases. This has the effect of letting
sunlight in, but preventing the heat from escaping. In order to keep
Mars at about the same temperature as Earth, all we’d have to do is add
enough Carbon Dioxide, Methane, and Water Vapor to Mars’ atmosphere.Want
to know something neat? If we’re going to move 20% of our atmosphere
over there, we may want to move 50% of our greenhouse gases with it,
solving some of our environmental problems in the process.
These
greenhouse gases would keep temperatures stable on Mars and would warm
the planet enough to melt the ice caps, covering Mars with oceans. All
we’d have to do then is bring some lifeforms over and, very quickly,
they’d multiply and cover the Martian plane tin life. As we see on
Earth, if you give life a suitable environment and the seeds
forgrowth/regrowth, it fills it up very quickly. So the prospects for
life on a planet with an Earth-like atmosphere, temperature ranges, and
oceans are excellent. With oceans and an atmosphere, Mars wouldn’t be a
red planet any longer.
It would turn blue like Earth! This would
also be good for when the Sun heated up in several hundred million
years, since Mars will still be habitable when the oceans on Earth boil.
But there’s one problem, Mars has that Earth doesn’t, that could cause
Mars to lose its atmosphere very quickly and go back to being the desert
wasteland that it is right now: Mars doesn’t have a magnetic field to
protect it from the Solar Wind. The Earth’s magneticfield, sustained in
our molten core, protects us from the Solar Wind. Mars needs to be given
a magnetic field to shield it from the Solar Wind. This can be
accomplished by either permanently magnetizing Mars, the same way you’d
magnetize a block of iron to make a magnet, or by re-heating the core of
Mars sufficiently to make the center of the planet molten. In either
case, this allows Mars to have its own magnetic field, shielding it from
the Solar Wind (the same way Earth gets shielded by our magnetic field)
and allowing it to keep its atmosphere, oceans, and any life we’ve
placed there. But this doesn’t tell us how to accomplish these three
things. The third one seems to us to be especially difficult, since it
would take a tremendous amount of energy to do. Still, if you wanted to
terraform Mars, simply these three steps would give you a habitable
planet.
The hypothetical process of making another planet more Earth-like has been called terraforming,
and terraforming Mars is a frequently mentioned possibility in
terraforming discussions. To make Mars habitable to humans and earthly
life, three major modifications arenecessary. First, the pressure of the
atmosphere must be increased, as the pressure on the surface of Mars is
only about 1/100th that of the Earth.
The atmosphere would also
need the addition of oxygen. Second, the atmosphere must be kept warm. A
warm atmosphere wouldmelt the large quantities of water ice on Mars,
solving the third problem, the absence of water.
Terraforming Mars
by building up its atmosphere could be initiated by raising the
temperature, which would cause the planet’s vast CO2 ice reserves to sublime and become atmospheric gas.
The
current average temperature on Mars is −46 °C (-51 °F), with lows of
−87 °C (-125 °F), meaning that all water (and much carbon dioxide) is
permanently frozen.
The easiest way to raise the temperature
seems to be by introducing large quantities of CFCs
(chlorofluorocarbons, a highly effective greenhouse gas) into the
atmosphere, which couldbe done by sending rockets filled with compressed
CFCs on a collision course with Mars. After impact, the CFCs would
drift throughout Mars’ atmosphere, causing a greenhouse effect,which
would raise the temperature, leading CO2 to sublimate and
further continuing thewarming and atmospheric buildup. The sublimation
of gas would generate massive winds,which would kick up large quantities
of dust particles, which would further heat the planet through direct
absorption of the Sun’s rays. After a few years, the largest dust storms
would subside, and the planet could become habitable to certain types
of algae and bacteria, whichwould serve as the forerunners of all other
life. In an environment without competitors and abundant in CO2, they would thrive. This would be the biggest step in terraforming Mars.
Conclusion
The
problem of creating a sound source of energy on Mars is of main
importance and related to the capacity of transportation from Earth to
Mars, very limited in the early stages of Mars colonization, and to the
capacity of producing the rough materials in situ. Consequently the most
important parameter that will govern the choice for one or another
means of producing energy will be the specific weight of the powerplant.
Besides then uclear sources, that most probably will face major
opposition for a large scale use, the onlyapplicable source that remains
valid is the solar one. As far as the solar flux is almost fourtimes
fainter on Mars than on Earth, the efficiency of PVC remains very
doubtfull, although it stands as a primary candidate.
This is why
the construction of the gravity assisted air accelerators looks like a
potential solution, especially when rough materials will be availableon
Mars surface itself. The thermal efficiency of the accelerator for
producing a high power draught and the propulsion of a cold air turbine
remains very high and attractive. The largearea of the solar reflector
array is still one of the basic drawbacks of the system, that only could
be managed by creating very light weight solar mirrors, but still very
stiff to withstandthe winds on Mars surface.
SOURCE: Potential of the Solar Energy on Mars – Dragos Ronald Rugescu and Radu Dan Rugescu
No comments:
Post a Comment