MARS 1: MISSION IMPOSSIBLE Pt.1 The story of Mars
- Zane Houser
- Feb 20, 2017
- 4 min read
Mars the red planet, is named after the roman god of war. A planet that has inspired our imaginations since long before it was called Mars. Now, in the modern era, it inspires a new dream.....colonization. but what is Mars like? what will people have to endure to survive? Is it possible one day Mars could look like Earth or is the prospect just another pipe dream to keep the masses interested in space exploration and the idea of life beyond Earth.
So lets talk about Mars itself. The red color of the martian surface is due to iron oxide present in the soil, so we could otherwise refer to it as the rust planet. Mars formed about 4.6 billion years ago, roughly the same age as Earth. So, what happened to Mars to make it, well, Mars?
About 4 billion years ago it is theorized that a Pluto sized object collided with Mars. Planetary astronomers came to this hypothesis by noticing the differences in geography and topography as indicated by the topography map below and the ultimate question of how did Mars get its two moons, Phobos and Demos.
About 40% of the martian surface is a low lying smooth, relatively featureless plain called the north polar basin or the borealis basin. Which was created by a low velocity object traveling 6-10 Km per second at a oblique angle with a diameter of about 1,600 to 2,700 km across (about 990 to 1,680 miles.) Which resulted in what just might be the largest impact basin in the solar system, creating the martian surface dichotomy we see today. The difference in the martian high/low points is about 30km from the top of the Olympus Mons (largest volcano in the solar system) to about 8.2 km below the zero altitude point. The basin in the northern hemisphere of the martian system is one of the smoothest surfaces found in the solar system. The southern hemisphere of Mars is high, rough, heavily cratered terrain, which ranges from 4 to 8 kilometers (2.5 to 5 miles) higher in elevation than the basin floor. The difference in Earth's highest and lowest point (Mt. Everest and the Mariana Trench) is 19.7 km which means Mars is three times more rigid than Earth. to better display the dichotomy of the martian surface observe the picture that portrays Mars with liquid water on the surface below and notice how the planet appears to have two "faces", a feature that was a result of the impact.
"The impact would have to be big enough to blast the crust off half of the planet, but not so big that it melts everything. We showed that you really can form the dichotomy that way," said Francis Nimmo of the University of California, Santa Cruz.
This event in proto-martian history effected the future of this system which otherwise might have looked similar to Earth, with plate tectonics and meteorologic activity but why did a large impact end the planets hope of being a life-sustainable world beyond our own? The answer has to do with magnetism on a colossal scale and the lack of it.
Every planet has a core, whether or not that core is molten or solid, it serves a vital purpose for the prosperity or doom of life as we know it. You might remember the movie "core" where they travel to the center of the Earth and use nuclear weapons to "jump start" the Earth's dynamo to prevent the magnetosphere from dissipating. But is such a thing even possible? why is a magnetosphere so important?
A magnetosphere is the region surrounding a planet where the planet's magnetic field dominates. Because the ions in the solar plasma are charged, they interact with these magnetic fields, and solar wind particles are swept around planetary magnetospheres. Life on Earth has developed under the protection of this magnetosphere.
Now you might like to think that a planets core is just this massive area at the center of a planet that is essentially just unimaginable amounts of magma... But this large mass of molten rock is a core comprised of heavier elements, in Earth's case, we have a molten iron-sulphur-silica core.
The core, well rather a fully active core, is a very complex system. "These processes include thermochemical convection and a variety of instabilities driven by irregularities in rotation, such as precession, libration, and tides. The spectrum of fluid motions in these experiments ranges from turbulence and inertial wave motions at high frequencies to global-scale zonal flows at low frequencies, and they result from the interplay between buoyant forces, rotational effects, melting and solidification, magnetic fields, and the spherical geometry of the core."
Unfortunately for Mars.....its core is just about dead......solid, cooled off from that early planetary collision that disrupted the natural convection processes and flow of the liquid super heated elements. This is data from a simulation of the impacts effect of a Pluto-mass object on the core of Mars and its long term effect.
Over time the martian core cooled..... less heat means less core activity, which is a vital component in the formation and the maintaining of a strong magnetosphere.
This is a comparison of strong/weak magnetic forces on a planetary scale of Mars and Earth. The notation nT is the (SI) unit of magnetic field intensity. At the Earth's surface the total intensity varies from 22,000 nanotesla (nT) to 67,000 nT. Notice Mars does have magnetic activity but it is not uniform to the planet and is theorized that it is magnetized rocks and other elements in the crust magnetized from the original core.
If you would like to get even deeper into the martian dynamo check out this link to vol 28 no.21 of the geophysical research letters "the global magnetic field of Mars and implications for crustal evolution".
In the next article I will dig deeper into the impact of the conditions of Mars, to an expedition and possibly colonization Is it REALLY possible? Or is it just false hope and we should focus on the world we live on now?
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