Orbital Arsenal
What those weapons will be will depend on how well the technology develops, but potential future systems include space planes capable of striking targets anywhere in the world in a matter of hours, 20-foot-long satellite-launched "rods from God" that fall from the sky with tremendous force, orbiting mirrors that flash laser beams to distant targets, electromagnetic-pulse weapons that fry satellite electronics, "tugboats" that push satellites into new orbits, satellites that spy on other satellites, and microsatellites that disable or destroy larger satellites.
Among the most pressing demands that space access can alleviate is high-speed, worldwide delivery of weapons. Future hypersonic unmanned space planes will use the advantages of spaceflight to strike anywhere in the world within two hours, a capability dubbed "prompt global strike." The Air Force envisions a system that consists of two vehicles: one to make the trip, and a second to deliver the bombs. Initially, a small rocket will serve as the launcher, and the bombs could be carried on board a gliding, self-steering vehicle with a 1,000-pound payload called the Common Aero Vehicle (CAV).
Later, in maybe 15 years, the Air Force plans to replace the rocket launcher with a reusable hypersonic cruise vehicle capable of carrying 12,000 pounds up to 9,000 miles. The unmanned aircraft will take off from a runway and use a scramjet engine burning liquid hydrogen to reach hypersonic speeds. The engine will be repeatedly shut down and re-ignited to send the craft skipping across Earth's upper atmosphere like a stone. The vehicle could deliver multiple CAVs or other payloads.
A program called Falcon is a testbed for some of these technologies. Jointly sponsored by the Air Force and the Defense Advanced Research Projects Agency (DARPA), Falcon is developing a Small Launch Vehicle and Hypersonic Technology Vehicles to demonstrate possible propulsion systems.
Developing a global strike capability isn't just a technological challenge-it's a political one as well. One big concern is that the leaders of countries such as China and Russia might have a hard time convincing themselves that the U.S. wouldn't hide nuclear weapons inside a CAV gliding at Mach 20. Sensitive to this concern, Congress has directed that none of the funds allocated for CAV research be used to develop or test a vehicle that includes any nuclear or conventional weapon. The decree leaves the Air Force in the awkward position of developing a weapons carrier that won't carry weapons.
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