Kinetic bombardment
From Wikipedia, the free encyclopedia
- For the generic concept of attacking a planetary surface from orbit, please see Orbital bombardment
A kinetic bombardment is the act of attacking a planetary surface with an inert projectile, where the destructive force comes from the kinetic energy of the projectile impacting at very high velocities. The resulting extreme force can be explained by the formula EK = 0.5mv2, where Ek is the kinetic energy, m the mass of the object and v its velocity. The concept is encountered in science fiction and is thought to have originated during the Cold war.
Other non-orbital bombardment with kinetic projectiles such as lobbing stones with siege engines such as catapults or trebuchets are considered siege warfare, not kinetic bombardment.
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[edit] Real life concepts and theories
[edit] Project Thor
Project Thor is an idea for a weapons system that launches kinetic projectiles from Earth orbit to damage targets on the ground. It is said that, at some point in history, the concept originated in a classified study for the United States Air Force in the 1950s.
The most described system is 'an orbiting tungsten telephone pole with small fins and a computer in the back for guidance.' The weapon can be down-scaled as small as several metres long, an orbiting "crowbar" rather than a pole.
The time between deorbiting and impact would only be a few minutes, and depending on the orbits and positions in the orbits, the system would have a world-wide range. There is no requirement to deploy missiles, aircraft or other vehicles. Although the SALT II treaty (1979) prohibited the deployment of orbital weapons of mass destruction, it did not prohibit the deployment of conventional weapons.
The weapon inflicts damage because it moves at orbital velocities, at least 9 kilometres per second. The amount of energy released by the largest version when it hits the ground is roughly comparable to a small nuclear weapon or very large conventional bomb. Smaller weapons can deliver measured amounts of energy as small as a 500 lb conventional bomb.
The "pole" shape is optimal because it enhances reentry and maximises the device's ability to penetrate hard or buried targets. The larger device is expected to be quite good at penetrating deeply buried bunkers and other command and control targets. The smaller "crowbar" size might be employed for anti-armor, anti-aircraft, anti-satellite and possibly anti-personnel use.
The weapon would be very hard to defend against. It has a very high closing velocity and a small radar cross-section. Launch is difficult to detect. Any infra-red launch signature occurs in orbit, at no fixed position. The infra-red launch signature also has a small magnitude compared to a ballistic missile launch. One drawback of the system is that the weapon's sensors would almost certainly be blind during reentry due to the plasma sheath that would develop ahead of it, so a mobile target could be difficult to hit if it performed any unexpected maneuvering.
While the larger version might be individually launched, the smaller versions would be launched from "pods" or "carriers" that contained several missiles.
It was most recently popularised by Jerry Pournelle, on his website, under the title "Project Thor."
[edit] Rods from God
Rods from God are a space-based kinetic energy weapon that has been discussed since the early 1980s.
The system would consist of tandem satellites, one serving as a communications platform, the other carrying a number of tungsten rods, each up to 20 feet in length and 1 foot in diameter. These rods, which could be dropped on a target with as little as 15 minutes notice, would enter the Earth's atmosphere at a speed of 36,000 feet per second - about as fast as a meteor. Upon impact, the rod would be capable of producing all the effects of an earth-penetrating nuclear weapon, without any of the radioactive fallout. This type of weapon relies on kinetic energy, rather than high-explosives, to generate destructive force.
They would conceivably be particularly well adapted to penetrate hardened targets, such as underground nuclear facilities.
There are major difficulties involved. One of them is where to position the rods. They need to be high enough to deliver enough energy upon impact, but not so high that they vaporize in Earth's atmosphere. The other difficulty is the number of satellites that would be required to cover a material portion of the Earth.
[edit] Rumours and speculation
There have been several rumours on the internet and the university physics circuit about a classified test of such a weapon in the Pacific Ocean in 1976. Unsubstantiated reports from several sources indicate a disturbance 150km North-West of the Hawaiian Islands similar to that of a "very small-scale nuclear detonation".[citation needed] This disturbance was widely believed to be a classified nuclear test by the US government, until recent years when rumours of an unsuccessful test of a space based weapon such as a railgun, mass driver, or kinetic bombardment projectile began to circulate.[citation needed]
[edit] In science fiction
- In the book Footfall by Larry Niven and Jerry Pournelle, aliens drop the Thor system on an American armored division.
- British author Peter F. Hamilton describes in his The Night's Dawn Trilogy, a weapon called a kinetic harpoon that is deployed from orbit and is used for precision strikes. The effect of the weapon can be enhanced by deploying several projectiles in a precisely calculated pattern as to produce shockwaves in the ground leading to an artificial earthquake.
- In the computer game Syndicate Wars, an all-powerful corporation called Eurocorp possessed the "Satellite Rain" weapon, which consisted of rods of a heavy metal alloy that could be fired from satellites. The rods would partially melt in the atmosphere and then impact in the target area at extreme velocity, causing massive devastation.
- In the "House of the Sun" by Nigel D. Findley (Paperback -- July 1995), a novel set in the Shadowrun universe, Project Thor is referred to as well as employed when tensions on the island nation of Hawai'i rise and a war almost begins between the nation and several mega-corporation and criminal organizations.
- In the book Star Wars: Shatterpoint, author Matthew Stover describes the "De-Orbiting Kinetic Anti-emplacement Weapon" or DOKAW, which consists of a continually orbiting metal rod with maneuvering rockets attached that can be called down on command to strike enemy targets.
- In issue 12 of Warren Ellis' Global Frequency comic, Miranda Zero and a hastily-assembled team of operatives race to stop the firing of a tungsten rod at Chicago from a malfunctioning secret orbital platform built by America's Strategic Defense Initiative.
- In the HALO series, the Magnetic Accelerator Cannon is a coil gun mounted on ships and orbital defense stations to protect the Earth and outer colonies from alien invasions. Interestingly, it is one of the few science fiction stories to depict kinetic bombardment being aimed away from the Earth instead of towards it.
When taken to a significant fraction of the speed of light, kinetic warheads become relativistic kill vehicles.
