Do Not Let the Sky Fall!


Predictions that the world is about to end have been going on for centuries. Those predictions are extrapolated based upon the estimated effects of several long-term influences that include both natural and manmade disasters. However, the uncertain factor in those assumptions is human interference in nature, which will very likely lead to the termination of a very large percentage of the world’s population.

For humans, it will be the most terrible tragedy ever; but for nature, it will just be a normal process. The bad news, someday the world will end, and not just on Earth, but for comets, moons, planets, stars, and everything in our known Universe; the good news, probably not anytime soon.

The world did not end in 2012 as many feared. Predictions were wide-ranging, but they were all about the end of the world on our planet, while the rest of the universe continues spinning on as usual. There are, in fact, multiple scenarios for known risks that can have an impact on our planet. From the perspective of humanity, these risks could include the misuse of technology, nuclear wars, or global warming. Similarly, several natural disasters may pose a doomsday threat, including gravitational interactions with other objects in the solar system, the steady increase in the solar luminosity, or perhaps resource depletion. The latter natural phenomena are part of the structure of the Universe; human beings and their actions are just minor factors that could not prevent their occurrences.

Randomly moving stars may approach close enough to have a disruptive influence on the Solar System; this encounter can trigger an increase in the number of comets reaching the inner Solar System. Among the harmful effects resulting from a major impact event is a cloud lowering land temperatures by about 15°C within a week, halting photosynthesis for several months. The estimated time before a major impact takes place is expected to be at least 100 million years.

It is also expected that the Sun in about 5 billion years will reach its “Red Giant” stage. Stars convert hydrogen to helium to produce light and other radiation; as time progresses, the heavier helium sinks to the center of the star, with a shell of hydrogen around this helium center core. The hydrogen is depleted so it does not generate enough energy and pressure anymore to support the outer layers of the star. As the star collapses, the pressure and temperature rise until it is high enough for helium to fuse into carbon, which means that helium burning begins.

To radiate the energy produced by the helium burning, the star expands into a Red Giant. The Sun is likely to expand to swallow both Mercury and Venus, reaching a maximum radius of 180,000,000 km. The Earth will interact tidally with the Sun’s outer atmosphere, which would serve to decrease Earth’s orbital radius. These effects will act to balance the effect of mass loss by the Sun, and the Earth will most likely be swallowed up by the Sun.

Another reason for world’s end, which is one on a long list of extrapolations, is resource depletion due to overpopulation. Every species on Earth, humans included, will reproduce until their population exceeds the resources needed to sustain it.

Food per capita is going down, energy is becoming more scarce, and groundwater is being depleted. Although overpopulation is usually local, it has become now worldwide. After overextending the population, natural corrections will follow, often by famine, which will destroy a very large percentage of the population.

While we observe the world today we might think that we have already arrived at the world’s end as our current age is filled with cruelty and awfulness that we tend to shield our eyes from the mess we have made. Human beings are squandering the gift of time that they have been granted on this planet; however, hope lies in the fact that we still have time to correct our errors.


*The original article was published in SCIplanet, Environment (Summer 2014) issue.

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