We Will Destroy Your Planet (2 page)

Over 70% of the planet's surface conditions are in fact made up of liquid water, which makes it a very rich source of a very valuable commodity, especially for vessels travelling long distances.

Despite these impressive statistics, it should be made clear to you at this point that most of the bodies in the Solar system have basically the same chemical and elemental composition, but do not have a sentient native species, or, indeed, any known life forms. Likewise, the various comets and asteroids in the system are also very rich in iron and other metallic elements, and these would be far easier to acquire, mine and process, than an entire populated planet.

Water is also available in reasonable quantities on the Moon, Mars, Europa, and in comets. It is true that the amount of water in these other locations is far less than on Earth, but the amount of it on Earth is so great that removing it would be somewhat problematic, due to its bulk and mass. You could fill thousands of mile-wide ships and still not have made a noticeable difference to the Earth's sea level. Always assuming, that is, that you can get such a large ship with such a large mass on the surface in the first place.

The Earth is teeming with life in many forms, however all, as far as is known, are made from organic structures based around the element carbon. There are many different types of life form, from single-celled organisms, through microscopic virii, plants, lichens, fungi, insects, fish, reptiles, mammals, birds… As of 2011, it was estimated that there are around 9 million species on Earth.

The greatest number of animal – i.e. ambulatory and able to move around under their own power – species is in the insect kingdom. Most of them are so small you won't notice them, but there are over a million different species of insects. Mammals, although the dominant species on the planet in terms of size and intelligence, are the smallest group, with just over 5,000 species.

The number of true sentient species on the planet is somewhat open to debate, partly because of differences of opinion over what constitutes sentience, and partly because the dominant life form – humanity, a bipedal upright type of largely hairless ape – is extremely parochial and has a very self-centred view of their world. It is becoming increasingly acknowledged among educated humans, however, that there are other sentient species sharing the planet with them.

As well as other species of ape, some of which have been taught sophisticated forms of communication, it is considered that some cetacean (ocean-based mammals) species, and dolphins in particular, are at least as intelligent as humans.

Space is as big as they say, and it's very important to decide upon the means of traversing such huge distances that will best suit your species and your battle plans.

If you hope to establish a system of being able to provide regular supplies and reinforcements, and to transport prisoners or resources back to your home, you will definitely need some form of faster-than-light travel, be it by warping space or using wormholes, so that there is effectively a shorter distance between your home and Earth, or by hyperspatial drive that allows you to slip outside the usual rules of the universe and move more quickly than light could under the physical laws of normal space.

Even Earth's scientists have established the existence of tiny wormholes, connecting the Earth to the Sun, in one case, but none large enough to travel through. However, if you have developed a technology that allows for the transmission of matter across space – or, better still, that breaks down matter into a data stream that can be reassembled somehow at the destination – you may find it worth trying to combine that technology with wormholes, in order to transmit your forces directly from your planet to Earth, without having to worry about building or navigating ships in between.

If you have not yet achieved a level of technology that allows for such molecular reintegration, it would also be worth looking into transmitting data in the guise of signals to be decrypted, which would include the schematics for autonomous AIs and the programming to operate them. Humanity could then construct such machines, which would follow your programming. This is also a good way to prepare the planet for your arrival after a longer relativistic journey, if you do not have faster-than-light travel.

Such slower forms of approach by starship would require – unless you are a race of very long-lived individuals – either some form of suspended animation for your forces, so that they don't age and die during the years, potentially even centuries or millennia, that it would take to get there, or a generational starship, in which the occupants breed under controlled conditions, and each new generation is trained for its part in the mission.

These are perhaps the most easily practicable types of travel to Earth, especially for those of relatively limited technological development, but they have the disadvantage of requiring you to bring along everything you could possibly ever need – which means a very large ship or fleet in the first place. This approach is perhaps best used by those who have lost their homeworld and are looking for a new one, or by those who are nomadic, and so, again, have no home to require backup from.

It is also possible that you are a naturally spaceborne species, which requires no separate artificial means of space travel. In this instance, it would seem unlikely that you would actually need to visit a planetary surface at all – and, indeed, may not be physically able to – but if you do have an ability or requirement to visit the Earth, then it's best to proceed at your own natural pace.

Whatever your specific type of space travel, if you're coming by starship or natural spaceborne ability, your initial approach to the Earth before landing would best be made from inside the Earth's orbit, which means cutting across the planet's orbital from the far side of the Sun. You should then approach the planet from the southern side of the planet's equator, with the Sun behind you. Your target area should be a region on the surface just on the sunward side of the day/night terminator, where the Sun is just rising.

If you have already, through reconnaissance, chosen a particular landing area, you will have to time the approach correctly to descend just after sunrise. If you have agents or sensors on the surface ahead of your force's arrival, you should have them direct you to approach on west-south-west course as seen from the surface.

This will minimize your chances of being detected on approach, even by infrared telescopes and other of the Earth's most sophisticated scanning equipment. A recent asteroid explosion in the Earth's atmosphere took the inhabitants completely by surprise by approaching from this very angle.

Depending on how many ships you have brought, and their size and mass, it may be necessary to station some of them offworld, either as a relay point, command and control centre, observation post, or simply because they are too large to land safely. The best locations in which to station such vessels out of the line of fire from Earth are either on the dark side of the Moon – which has the advantage of allowing a surface landing – or at one of the Lagrange points in either the Solar-Earth or Earth-Moon orbital relationships.

The Lagrange points are five points around the orbits of a related pair of astronomical bodies, one of which orbits the other. In these five locations, a small body can maintain a stable position relative to both. In the case of the Earth, there are two relevant relationships to consider: The Earth's orbit around the Sun, and the Moon's orbit around the Earth. Each of these orbital relationships has its own set of Lagrange points.

Three of the points require effort to maintain that stable position. The L1 point is close to the orbiting body (the Earth in the Sun-Earth relationship, and the Moon in the Earth-Moon one), where its gravitational field balances out the gravitational pull of the larger body. Here the orbiting body's gravity increases the orbital period of a smaller body – such as a ship – to the point where said ship will have the same orbital period as that body. Where the Sun-Earth relationship is concerned, this point is about one million miles sunwards of the Earth.

The L2 point is directly opposite L1 but on the other side of the orbiting body – or a million miles outward from the Earth. L3 is in the same position as the orbiting body, but directly opposite on the far side of the parent body – i.e. 93 million miles from the opposite side of the Sun.

Of these three Sun-Earth points, L3 is particularly unstable, partly because the Earth's orbit is elliptical rather than circular, and partly because the gravitational effects of the other planets, especially Venus, affect it. Before these facts were confirmed, human storytellers liked to imagine there could be some kind of alternate Earth at the Sun-Earth L3 position, however this is neither the case nor even possible. The L1, 2 and 3 points in the Earth-Moon system are unstable and move around, as the Moon is also in an elliptical orbit. Your navigators should be able to work out the relevant positions.

Anything parked in the Earth-Moon L1 or L3 points would be highly detectable from Earth, and neither are strategically wise choices, for that reason. There is also usually a space observatory maintained by humanity at the Lunar L1 position, whose absence or damage would be noticed, as would a neighbour. The Lunar L2 position is a better option, as it is on the far side of the Moon, but simply landing on the dark side of the Moon would be more energy efficient.

The best positions, however, in which to park your ships are the two so-called Trojan points, at L4 and L5: 60 degrees of arc ahead of and behind the Earth's orbit, and the same position in the Moon's orbit around the Earth. Small bodies can maintain stable position at either of these positions, and the positions are far more fixed and stable than any of the other three.

Obviously, positioning ships at the Earth-Moon L4 and L5 positions, with a base on the Moon itself, gives a good range of coverage relatively close to the Earth, with low energy requirements for station-keeping. These positions may, however, be within missile range of Earth's defences. The Sun-Earth L4 and L5 positions would certainly be safer, but have the disadvantage of being much further away.

Ultimately, the choice is yours.

If you are coming from a parallel universe or dimension, it is unlikely that you will need to consider planetary defences, as you will be able to materialize on the surface, in the ocean, or within the atmosphere. Depending on your type of species, you will need to establish by testing with scouts or reconnaissance drones exactly where and in what environment you will arrive. You may have to cross from a specific area or set of circumstances in your home dimension, or you may not.

If your species is not human, but either a different terrestrial species that gained dominant sentience ahead of humans, or some form of supernatural entity, you will have to be extra careful about being detected upon arrival, lest you alert human security forces, or, indeed, find yourself a subject for study and experimentation.

In particular, if your species relies on innate abilities that humans could take for supernatural powers, you may not need traditional technology to move between dimensions, though it is always possible that establishing some form of mental link with humans on the target side of a dimensional bridge may help form a bridgehead. If nothing else, playing the part of a deity or similar entity will help smooth the process of intelligence gathering about your target area.

It is possible for time travel to result in the creation of parallel worlds, or at least the branching off of parallel timelines. If this is the case between your home dimension and the current Earth, you may be able to effect a transition from one timeline to the other by travelling in time and undoing the event that created the parallel timeline.

This is a dangerous route to take, however, due to the risk of paradox, potentially resulting in either you never having existed, or creating a closed loop in which your actions are what created the timeline you originated from. This has especially been seen to happen when time travellers from the future attempt to change a past or present effect, where the unpleasant timeline is the result of violence in the target time zone.

This is possibly the simplest journey, unless you actually want to make a return trip after acquiring modern or future resources. Simply wait. Or, if you won't live long enough, build a suspended animation facility and ensure that you and your armed forces are preserved in a safe location – ideally in sealed caves, an underwater city, or an orbiting or Lunar facility – to be awakened at the appropriate time.

You can either set some kind of timing mechanism to awaken you after a set geological age, or program your computers to awaken you when a specific set of circumstances has been achieved. Please be aware that if you are from the far distant past of the Earth, the climate will certainly have changed, and possibly the actual biosphere as a whole. In particular, the levels of oxygen are presently very different today than in the past, with the percentage of oxygen in the atmosphere having peaked 300 million years ago at 36%, almost double its present concentration.