Space The Final Frontier
Technolgy not inveted yet, for all things listed below. Year 1999
In one interstellar-engine concept, charged particles streaming out at onethird the speed of light would provide thrust for a fusion-powered spacecraft.
The nearest star is a long way from Earth: Distances are in astronomical units, or AU. One AU is the distance between the Earth and the sun, about 93 million miles.
Fusion Ramjet
1. In the Bussard fusion ramjet concept, onboard tanks provide hydrogen fuel for fusion reactions that accelerate the spacecraft out of our solar system on its way to a target star.
2. Gigantic magnetic fields 6,000 kilometers in diameter "scoop" interstellar hydrogen to refuel and provide additional thrust.
3. The spacecraft coasts at high speeds.
4. The scoop again fills the tanks, and decelerates the craft.
5. Spacecraft enters orbit with fuel from tanks.
LightSail
Some tens of kilometers in diameter and just a few atomes thick, lightweight lightsails, 1., would be pushed by an orbiting laser beam powered by the sun for a 4.5 light-year trip to another star in 20 years.
2. After being pushed for months or years, the sail spacecraft would coast to the target star system.
3. A second-sstage sail would be used to decelerate; 4. then the lightsail goes into orbit around a selected planet.
Mater-Antimater
When matter contacts antimatter, they annihilate each other, releasing energy in greater densities than any other reaction known. In a beam-core engine system concept, hydrogen and anti-hydrogen are fed from a spacecraft's onboard storage tanks. They contact in chamber and the resulting products are directed out the back of the spacecraft by magnetic "nozzles" for thrust.
Delivery Service for Satellites
Like the space shuttle, the Space Access vechicle will make round trips. But its designers expect it to be unpiloted, cost much less to operate than the shuttle, and travel into space more frequently-perhaps as often as twice a week. The first application for the space plane will be to launch commercial satellites.
1. No launch pad repuired: With payload and upper stage stow inside, the Space Access aero spacecraft takes off from an port runway like an airplane.
2. The space plane climbs to about 150,000 feet using its ramjet engine, which then loses effectiveness in the thin atmosphere. A rocket engine takes over to propel the vehicle to 300,000 feet.
3. The space launcher's nose opens to release the upper stage and attached satellite payload. The tugboat-like upper stage then pushes the satellite into its designated orbit and releases it.
4. The large launch vehicle and the smaller upper stage are both reusable, with wings and landing gear. They glide back down from space for separate runway landings.
Ejector Ramjet Engine
A new engine developed for the space access vehicle, a modified type of air-breathing ramjet, reduces the amount of oxygen and fuel that must be carried along for the trip.
On start \up, hot exhaust from an off-line burner is injected into the engine duct. The fast-moving gas draws outside air through the inlet. H ydrogen is burned with the air, accelerating the vehicle and "ramming" more air into the inlet. When the speed reaches Mach 2.5 the burner shuts down.
Roton Rolled Out
A competitor to Space Access, Rotary Rocket Co. is developing a piloted, single-stage-to-orbit vehicle called the Roton. The company recently unveiled a demonstrator that will be used to test the Roton's rotor-blade landing system. The company plans to build two prototypes for orbital flight tests next year.