Mr. David Kelty
3 December 2012
Threats From Space on Earth
There are seven possible scenarios which scientists believe if occur, could naturally end this planet and humanity, the world as we know it. Orbital change, rotational change, collisions with the Earth, the big rip, the sun, black holes, and other systems going out of whack can cause events that could potentially cause an end to life on Earth. People have theorized about an end to the planet or people on it for most of time. However, the scenarios that will be explained are the most logical and probable scenarios that could occur.
An orbital change could affect everything on Earth. This is when the Earth moves closer or farther from the sun. The effect of something like this happening is detrimental to life on Earth. It would cause the entire planet to freeze or burn. A change like this could be extreme or very subtle. The amount of change would determine what would happen to life. It could either completely end or there could be a step up in the evolutionary chain and organisms would adapt to the new environment. In a solar system, near a star, there is a region of space that is possible for life to manifest. The Earth resides in the Sun’s Goldilocks Zone, or the distance from the sun that allows the Earth to be habitable (Villanueva)”. Going slightly inside or outside of this region during orbit could be detrimental to us all. Though the Earth has a slight wobble to its orbit, which causes seasons to vary in climate from year to year, drifting out of the Goldilocks Zone could cause all life on Earth to become remnants of the past. The Earth’s axis has a wobble to it that scientists believe over time will cause an orbital change, knocking the Earth’s orbit out of whack (Miles and Smith p.90). Over time this is what will cause an orbital change of the planet Earth to occur. An event like this could be gradual or fairly rapid. Depending on how long it takes for an event like this to take place would determine what would happen to the organisms on the planet. A rapid change would probably kill them off. A slow, gradual change could kill them off as well but it is more likely that it would cause a step up the evolutionary ladder.
If the Earth were to move closer to the sun after an orbital change, then the planet would dramatically heat up. Heating up the planet has various effects, one of the first of which is the spread of disease. This would cause most, if not all, of the organisms to die off. Whatever is left after the diseases have taken their toll will be scorched or burned up not much longer after the disease hits. Moving the Earth a minor fraction closer to the sun would cause a temperature increase so great that all life on Earth would parish if it were to occur.
If the Earth were to move away from the sun because of an orbital change, then the Earth would cool down dramatically. An event like this would cause the planet to freeze. Cooling the Earth would put organisms into dormancy, and evolution would pause. This would be because the organisms would be frozen along with the planet. If the planet were to ever heat back up, then it would cause life to restart back to the primordial stages of life as a protein.
If the Earth quit moving on its path around the sun, then it would cause drastic changes. An event like this would cause all the places on Earth to be stuck in one season (What If?). This would make only a small portion of the planet livable. The parts that would be uninhabitable would be facing the sun or facing black space. “The portion looking at the sun would be burning or scorched barren deserts. The portion aimed out into space would be extremely cold, frozen, tundra that would be too harsh for life to be possible (What If?).”
Along with an orbit comes the rotation of a planet. Both are necessary for a planet to work properly. However, they are very different. The...