Ten ways to destroy Earth – science fiction or daunting reality?

Planet Earth is composed of atoms of different substances. Lots of atoms.  That is, approximately 200,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 atoms, to be more specific. Most atoms are very stable, since it is energetically favorable for an atom to remain intact rather than be dismantled into its protons, neutrons and electrons. However, quantum mechanics tells us that there is a chance, although extremely small, that an atom will break apart despite being stable. In light of this, if a single atom can spontaneously breakdown, so can the 200,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 atoms that make up Earth,  simultaneously.  What are the chances this will happen? "Approaching zero" cannot even begin to describe how slim these chances are. As mentioned, the probability that a single, stable (non-radioactive) atom will break apart is very small. The notion that this will happen to such an incredibly large number of atoms, all at once, is nothing short of ridiculous.

Most particles surrounding us are made of "up" and "down" quarks, the most prominent examples being protons and neutrons. However, some subatomic particles may be composed of "strange" quarks (the term "strange" is of no scientific significance except to emphasize the astonishment of the scientists who discovered it). Strange quarks are unstable, and therefore the particles that contain them break apart rapidly into other particles. Theoretically, however, in case a strange quark remains stable for a long enough time, it will begin to collide with "normal" particles in a manner that will turn them into "strange" particle themselves. A chain reaction in which normal matter is turned into strange matter would ensue, and eventually the whole Earth would transform into a giant chunk of "strange" matter.

Such strange particles are sometimes formed as a result of the collisions taking place in particle accelerators; they are, however, unstable, and break apart rapidly. This "threat" gained some media attention due to the concern that an accelerator in the US will lead to the destruction of Earth in such a manner. Of course, the probability that a strange particle will remain stable for the time period required for such a chain reaction to initiate is tiny. Particle accelerators have been operating for decades, and Earth is still intact…

This phenomenon has been referred to in a number of science fiction books and films, describing scenarios in which strange particles are formed and lead to the annihilation of Earth, be it a result of a tragic mistake or of vicious foul play.

This issue was picked up by the popular press with regards to the CERN particle accelerator. The generation of a black hole requires vast amounts of energy, equivalent to all the energy stored in the mass of Mount Everest. However, this theory relies on the validity of gravitational theory as we have come to accept it. There are several contesting theories that claim that the force of gravity changes over small distances, implying that much smaller amounts of energy would be required for the generation of micro black holes. Hence, one can envision a scenario in which a black hole is generated through a collision in a particle accelerator. Such a micro black hole would start absorbing growing quantities of matter, until finally it would absorb the whole planet.

One shouldn't lose any sleep over this concern either. Even if the theories describing the generation of black holes in the new accelerator were to be true, we should keep in mind that black holes are constantly losing energy in a process known as Hawking radiation. The smaller the black hole is, the faster it will lose its energy and disappear. For this reason micro black holes are predicted to exist for such a short period of time that they wouldn't be able to absorb matter and cause any damage. In fact, micro black holes are being searched for by scientists at the CERN accelerator, since their existence would prove that gravitational theory needs to be amended.

Planet Earth is held together by gravity. One can compute Earth's binding energy, which is the energy required to disassemble the whole mass from which Earth is composed into tiny particles with negligible gravitational fields. The outcome of this computation is a vast amount of energy: 224,000,000,000,000,000,000,000,000,000,000 joules. This number is equivalent to the amount of energy generated by the sun over one week's time.

The villain scientist would wish to generate an explosion powerful enough to release the energy required to disperse Earth's mass into the endlessness of outer space. His weapon of choice might be a giant antimatter bomb. Each of the universe's particles is associated with an antiparticle, having the same mass but opposite electric charge. When a particle and an antiparticle meet, they annihilate each other and their whole mass is converted to pure energy.

Due to the interaction of cosmic radiation with the Earth's atmosphere, antiparticles are constantly being generated, and are immediately annihilated. In addition, small amounts of antimatter are generated for short periods of time in particle accelerators.

How much antimatter would our villain need to annihilate with "normal" matter in order to release the amounts of energy required for the destruction of Earth? Lots! Approximately 2.5 trillion tons of antimatter. Needless to say that the idea of producing such amounts of antimatter, let alone storing it, is ridiculous at best.

Nevertheless, smaller antimatter bombs are definitely a notion whose materialization in the not-so-far future should not surprise anyone.

Outer space is not a perfect vacuum. Particles and antiparticles are constantly generated and vanish. The most widely accepted theories state that the amount of energy trapped in this great void is enormous. A small volume equivalent to that of a standard light bulb contains enough energy to evaporate all of Earths' oceans. Unfortunately (or luckily – a matter of perspective), it seems that it is impossible to exploit this energy.

Should our fictional villain wish to destroy Earth with the energy of the void, he would have to devise a system to extract this energy, and then release it. As mentioned, the amount of energy trapped in the great void is so enormous, that our villain could harness it to evaporate the whole planet.

Of course, today there is no known technology to exploit this energy, and so this idea is only theoretical.

The universe contains a great number of huge black holes (known as supermassive black holes). Stars are constantly orbiting them and are collapsing into them. Even our own galaxy, the Milky Way, contains a huge black hole in its center. Obviously, if Planet Earth were to come near enough to such a black hole it would be absorbed by it and become part of its mass for eternity.

On his mission to destroy Earth, all our fictional villain would have to do is locate a black hole and push Earth towards it, or alternatively, devise a method to bring the black hole closer to Earth. The first part is easy as we are already familiar with numerous black holes. Of the ones we know, the one closest to us is 1,600 light years away.

The second part of the scheme our villain would find more challenging,as it's unclear how one can divert Earth from its orbit (maybe using really huge rockets?). Of course once the villain figures out how to accomplish this life would cease to exist on Earth, as it would travel away from the sun and the energy it provides it.

Even if the villain should succeed in diverting Earth and moving it closer to the black hole, the great distance of 1600 light years implies that carrying out this plan may take thousands of years.

This wicked idea was mentioned in the science fiction series The Hitchhiker's Guide to the Galaxy by Douglas Adams.

 

A mass driver (also known as electromagnetic catapult) is an apparatus designed for launching small objects to outer space without the use of a rocket engine. The energy is supplied by coils of wire which are energized by a magnetic field generated by superconductors. A successful launch requires that the electromagnetic fields be strong enough for accelerating objects to a velocity that is sufficient to escape Earth's gravitational field, similarly to how satellites or space vehicles are propelled by rockets in a conventional launch.

What may happen should our villain get hold of such a machine? One possiblity is that he could start digging holes in Earth and launch the dirt to outer space using his mass driver, and continue doing so until the whole Earth is gone.

The villain whom we have previously encountered, the one who had gotten his hands on the giant rockets that might help him propel Earth towards the nearest black hole, can actually save himself some precious time by exploiting this technology in a different manner; launching Earth on a one-way voyage towards the sun. Intuitively we may think that in such a scenario Earth would melt from the sun's radiant heat and eventually be absorbed by the sun. However, Earth would actually be torn to pieces before melting. This is because as we approach it, the sun's gravitational field becomes so strong that it would exert a gravitational force that is not constant across Earth's diameter, with the parts closest to sun being more attracted by it than those farther away from the sun. This effect is called tidal force.

This scenario can also take place should a giant asteroid hit Earth in a very particular angle, launching it towards the sun. This is, of course, extremely unlikely. In fact, such an event can be unquestionably ruled out for at least the next quarter century, otherwise this giant incoming asteroid would have already been identified.

Of course this method is somewhat problematic. Firstly, this operation requires that the villain generate enormous quantities of energy. Secondly, mass drivers are not efficient enough today and are limited to launching only small masses. This means that based on today's available technology it would take the villain hundreds of thousands of years to launch Earth piece by piece to outer space.

Everything in the universe is temporary; stars, solar systems and even whole galaxies. As time goes by we should expect an event that will annihilate Earth, or at least transform the conditions on it to ones that cannot sustain life. The nearest event is expected to take place in a few billion years, when the sun's internal "oven" will run out of fuel and it will die out, probably turning into a red dwarf. Earth, should it survive, will turn into a very cold planet.

In a different scenario, our solar system will be destroyed when the Andromeda Galaxy, the galaxy nearest our own Milky Way Galaxy, will collide with it. This is expected to occur in about 3 billion years.

How bothered should we be by all this? As mentioned, these scenarios are billions of years away from us, so we shouldn't lose any sleep over these either.

 

Science indeed provides potential villains with creative methods for the complete annihilation of Planet Earth; creative, yet at this stage still entirely fictional. In the forthcoming future it seems that we can all stay calm, as apparently Earth is here to stay. Of course, the conditions on Earth are subject to alterations with time and with man's doings, but this should be discussed in another article.

 

For viewing The History Channel program on which this article was based, click here.

 

Before we wrap things up, one thing is missing: number 8! Where has it gone? This one is open for your imagination. You can make your own wicked suggestions in our forum – so let's see where your imagination takes us.

 

And finally, before we are destroying it, let's enjoy another view of our magnificent planet:

 

Yaron Gross

Department of Condensed Matter Physics

Weizmann Institute of Science