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Life on Mars: a travel brochure for the Red Planet

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Life on Mars: A travel brochure for the Red Planet
If you like dramatic weather, dusty conditions and the most extreme natural landscapes in the solar system, the spectacular red planet of Mars could be your destination of choice.

How's the weather?

Driven by the fine, sunlight-absorbing dust that engulfs the planet instead of the water that triggers meteorological changes on Earth, the weather on Mars is characterized by dust storms, dust devils and raging winds. The two hemispheres of Mars, like those of Earth, experience four seasons, and carbon dioxide condenses and forms seasonal frost deposits during the Martian winter. The weather on Mars is mostly predictable, and while the average global temperature is cooler than Earth at 55°C (-133 to 27), temperatures can rise and fall quickly. With an atmosphere only 1% as thick as Earth’s and no magnetic field to shield from solar flares and cosmic rays, the Red Planet offers harsh conditions that are much more severe than on Earth.

Keeping the dust out

The dry Martian atmosphere contains a significant amount of suspended dust. More like flour than the sands of Earth, these small grains of dust can be as fine as cigarette smoke. Unlike most common Earth sand and fuzzy dust, Martian dust particles are sharp and oddly shaped. As solar heat warms the atmosphere, it moves the air, sending the dust swirling. Regional dust storms generally persist for a few weeks before dissipating, but there are occasional planet-wide dust storms that turn the air orange and hide the surface from view. Dust storms are more common in late August, at the Red Planet’s closest approach to the sun.

Spectacular dust devils, the visual markers of a wind vortex, pick up dust off the surface of Mars, creating criss-crossing tracks as abstract as a Jackson Pollock painting. Although the lower atmospheric pressure means they don’t have much force behind them, the fast moving Martian dust devils can be up to ten times taller than those found on Earth, up to ten kilometers high. They are often electrically charged, creating electromagnetic interference that can affect the function of electronic equipment. And they cause extreme static cling, making it tricky for astronauts to completely clean themselves off when re-entering their habitat at the end of the day. Mars habitats may end up with a thin film of dust coating everything inside despite best efforts to keep them clean.

Dust is treacherous for Mars expeditions, causing static charges, jammed spacesuit joints, leaking air pressure from seals and spacesuits, dirty and weakened solar power panels, shorting equipment, clogged filters, obscured warning lights and scratched windows and lenses. If dust does get into the crew’s habitat, it can irritate lungs, skin and eyes. Dust storms block visibility and communication. The crew won’t be completely defenseless, however: dust can be removed or reduced from environments and machinery through electromechanical methods, including tilting, shocks or ultrasound that break the electrostatic (static-cling) effect of the dust, as well as air filters and dust-repellant coatings.

The view from Mars

The Red Planet moniker is a bit of a misnomer. Early images seemed to show Mars with a dark pink sky, but to scientists’ surprise, a colour correction conducted with images from the 1997 Pathfinder mission revealed the Red Planet’s true colour. The daytime sky offers a warm-hued ambiance with a brownish-yellow butterscotch colour.

The Martian dust active in the planet’s atmosphere can lead to sunsets and sunrises opposite to those of Earth: instead of our blue-sky with pinkish/red effects around the sun, Mars presents pinkish-red sunsets/sunrises with touches of blue in the vicinity of the sun. The effects are caused by the vast amounts of Martian dust in the atmosphere. Illumination of the dust in the atmosphere also causes twilight to last last much longer.

The terrain of Mars is characterized by exaggerated extremes, including massive canyons, such as Valles Marineris along the equator, and Olympus Mons, the tallest volcano in the solar system. At 25 kilometers high, Olympus Mons is three times higher than Mount Everest. Scenic impact craters, such as the enormous Helias Basin, along with channels, gulleys and low lying plains that were once rivers and ocean beds are worth exploring.

Emergency spacesuit repair

Spacesuits are designed to protect astronauts, but like scuba diving equipment, are not entirely fail-safe. In the event of a tear or loss of pressure, astronauts may have up to 20 minutes of emergency oxygen and must work quickly to:

1. Assess risk. The larger the hole, the greater the risk, and the lower the amount of time until the O2 runs out.

2. Interim patch. A temporary seal of some special-purpose material may help.

3. Find safe environment. Return immediately to the spacecraft.

4. Repair. Once safely inside, the astronaut can repair the suit with special adhesives and equipment

Excercise and bunny hops

Although it’s stronger than that of the Moon, the surface gravity of Mars (3.71 meters square) is only 38 percent of Earth’s (9.81 meters square). In order to counteract the detrimental health effects of low gravity on bone and muscle tone, visitors will still have to exercise while on the surface of Mars. Visitors to Mars can also experiment with low gravity movement. Astronauts exploring the Moon’s surface discovered that in a bulky space suit, bunny hopping, or lightly jumping across the surface was actually more efficient than walking. Martian explorers might develop some unique forms of locomotion of their own.

Getting used to the 24.65 hour day

Thirty-nine minutes may not seem like much of a difference, but when your body clock is set to the Earth day, adjusting to the longer Mars day isn’t easy. During NASA’s Mars Exploration Rover Mission (2003), scientists and engineers working as mission control crews lived on Mars time on Earth, keeping in direct contact with the rovers in shifts, 24 hours and 39 minutes a day, seven days a week. Although some of the crew adapted to the rotating schedule, many found it difficult. Wearing special watches that kept Martian time, the crew coped with the stress and fatigue that comes with the disruption of one’s circadian rhythm plus the difficulty of juggling a family and social life while living in a different time zone.

Race to Mars: Drawing of the Atlantis surface habitat (missing Illustration)
The Mars Surface Habitat

During their stay on Mars, visitors will live in a surface habitat. Some missions call for the habitat to be pre-launched into space in multiple parts and pre-assembled in low-Earth orbit. It will be sent to the planet ahead of the crew, and will be ready and waiting on the surface by the time the astronauts get to Mars. Designs vary, with the one shown here shaped like a cylinder with two conic end domes, and standing a meter off the ground for convenient underside access. The external structure includes an octagonal frame for easy landing gear and equipment attachment. An advanced Extra-vehicular activity (EVA) facility features equipment storage, and the habitat’s airlock leads to an external porch and ladder. A negative pressure space is electrostatically charged to remove dust. A rear emergency exit includes its own pressure port.

Growing food on Mars

Chances are that on a first mission to Mars, the crew will be bringing along all of their food supplies, but future crews stationed on Mars for longer durations may grow their own food in greenhouses or underground using light from solar collectors. Long cycles of light and high carbon dioxide levels on the Red Planet will stimulate plant growth, although the plants are likely to be hydroponic (grown in water and chemicals) until the constituents of the Mars soil are better known. The Mars-grown food-supply could consist of:

* Cereal (wheat and rice)

* Legumes for protein

* Sweet potato or white potato for complex carbs

* Vegetables (lettuce, tomato, broccoli)

* Herbs, including onion and garlic.

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