Death Rock - By The Piper

What happens when a mile-wide chunk of rock traveling through space smashes into Earth? Why, The End of the World, of course. Welcome to another installment of the series that dwells on cataclysm and Armageddon. As usual, I will be presenting scientific evidence for another global calamity, but please keep in mind that this will mostly be speculation and is in no way a promise or prediction of future events. This work is being done purely as entertainment and any doomsday cult proceedings or other self-destructive activities are not the responsibility of the author or the magazine. Now, having said that, lets get on with it.

As you probably know, space is not completely empty. Aside from fictional farm boys toting energy weapons, it has dust, ice, gas, and various forms of matter and energy existing in and traveling through it. Some of these travelers are remnants of previous planetary bodies, and formations of ice and matter from the birth of the solar system. Some of these are huge, though small on a planetary scale. Earlier this week, a relatively small (over 1,000 feet wide) asteroid passed by the Earth at a distance roughly equal to twice the distance to the moon. So what, it missed us, right? Yes, it missed us, which is a good thing when you consider that the energy released from an impact with an object of that size would have been enough to devastate an area basically equivalent to a medium-size country like England or France. The scary part is that we only spotted this object a couple of weeks before it made its pass. It only gets better when you consider that this object is also in orbit around the sun (along with numerous others) and will be back for another pass.

NASA's Near-Earth Object Program defines a Near-Earth Object as an object that has its closest pass to the Sun within 1.3 AU. One AU (Astronomical Unit) is the distance between the Earth and the Sun (approximately 93-million miles). This means that Near-Earth Objects are those that pass within about 28-million miles of the Earth's orbit. The categorization is further broken down by classification as a comet or asteroid (NEC and NEA respectively). Comets, from the outer solar system and mostly composed of ice and dust particles, and asteroids, being mostly rock or metals and typically from the asteroid belt between Mars and Jupiter, are the remnants from the formation of the solar system around 4.6-billion years ago. Scientific babble; there probably aren't very many of these rock things, anyway. According to NASA, 1,736 NEOs have been discovered, with 555 of these being asteroids with a diameter of approximately one kilometer or larger, and 367 NEOs being classified as Potentially Hazardous Asteroids (PHAs). The current estimate of the number of undiscovered NEOs larger than one kilometer is 1,000. NASA is hoping to have discovered 90% of these within the next 10 years. A long time considering how close the recent miss got before anyone noticed it.

You have probably seen a film in the past 10 years that has had a giant asteroid as its plot device. Hollywood has allowed you to see some of the possible horror in glorious detail through the use of special effects. Some of these have involved groups of heroes traveling to the offending rock and either trying to blow it up or knock it off course. Suppose that a chunk of rock over six miles in width were to impact the planet. To find out the end result, you would probably have to ask the dinosaurs. Oh, wait, they're extinct! It is currently believed that the dinosaurs were wiped out by just such an occurrence, and they weren't the only ones. It is believed that 75% of the life on the planet was killed by this event. The effects of the Earth being hit by such an object would be nothing short of cataclysmic. All matter at ground zero would be vaporized for many miles around as the force of over 100-million hydrogen bombs detonates against the Earth. This would send a shock wave rating somewhere around 12 on the Richter scale through the planet and would be felt the world over. This impact and its associated shock could carve out a crater over 100 miles wide. If it hits on a land-mass, the skies around the globe would be darkened by dust within days. Without sunlight plants cannot survive. Without plants animals cannot survive. Without plants and animals it is doubtful that the majority of humanity would survive. Of course, this is not counting those lucky millions who were killed during the impact and its related firestorm. A population center hit by an asteroid as small as 50-yards across could kill millions. A six-mile giant hitting a population center is an unimaginable death toll. If this projectile from space were to smash into the sea, there would be tidal waves to wipe out people and everything else along the coastlines, but the environmental effects might be lessened overall compared to a huge asteroid striking land. Immense explosive detonation, sonic shockwave, firestorms, tidal waves, acid rain, flooding and global atmospheric dust clouds make this scenario a particularly devastating one that could lead to the extinction of much of the Earth's life. A comet as small as one mile across could spell the end for over a billion people through impact deaths and eventual starvation. A comet that has spent the past 10,000 years working its way around its orbit could be heading straight for us right now and we might not even know it is coming. The average speed for an asteroid is some 10 km per second (36,000km/22,000 miles per hour); 20 km per second for those whose entire orbit is within the solar system; and 50 km per second for comets making a pass from the outer solar system.

On June 30 in 1908 a small asteroid (estimated at 30 to 60 meters across) grazed the surface of the Earth and exploded about three miles in the air above Tunguska, Siberia. The force of this detonation was roughly equal to a nuclear bomb and more powerful than either of the bombs used during World War II. Most of the trees in an 18-mile radius were leveled. One hundred-twenty-miles away, items on shelves and some carpenters working on a building were knocked down. An account from the incident details a sky filled with fire, being knocked some 20 feet to the ground and searing heat some 60 miles away from the blast. Three-hundred-miles away people could see the fiery cloud and hear the deafening sound of the explosion. Seismic vibrations were recorded from 600 miles away, and in England (2,200 miles away) a weatherman noted unusual pressure from the region. All of this from an object possibly as small as 100 feet across, which luckily detonated over a very remote region. We do not possess the detection capabilities to spot objects this small until right before they hit, and some estimates put the number of small NEOs at over 100,000.

Interestingly, it may be these same dangerous travelers that brought life to the planet in the first place. Some comets contain carbon-based molecules and ice, which are two of the primary components for life (as we know, anyway). Life is believed to have begun on the Earth some 3.8-billion years after a billion-year period of heavy comet and asteroid bombardment. Prior to this point, the planet was too hot to allow for water or carbon-based molecules to exist in sufficient quantities to support life. Some scientists say that because there was little water or carbon-based molecules on the Earth after the bombardment, they must have come from somewhere else. Since comets and asteroids often contain abundant quantities of both of these, they surmise that they may be the source of the building blocks for life on Earth.

This is the sort of duality that often occurs with destructive forces. Scorched forests eventually spring back with bright, green life and one creature's demise is another's ascension. Our primitive mammal ancestors were able to survive the events that killed off most of the world's population and now we sit atop the food chain. Will the next cosmic event unseat us? Is the end near? Maybe. Check out The End of the World next time and you just might find out.