Space has always been the ultimate frontier for man kind. People have been gazing at the night sky for thousands of years and have dreamt about reaching those distant stars which shined so bright. A half decade ago, the first humans ventured into space and soon afterwards Neil Armstrong said his famous words on the Moon. Since then, a new term has been invented, space tourism. Land is being sold on the moon, people are allowed to travel on a space shuttle (for a very significant sum, but nonetheless, it is possible).
Incredible as it may seem, the new frontier is becoming more and more accessible. However, safety is still a concern. The invention of the space shuttle was a huge improvement in this field, but challenges are still present and the technology is far from being perfect (for example Challenger and Columbia).
Several concept shuttles, rockets, freighters and even vehicles of domestic use exist or are being developed at the moment.
The White Knight and SpaceShipOne
The White Knight is a high altitude carrier aircraft from which SpaceShipOne, the award-wining concept suborbital passenger carrier could be launched. It is possible that this design would be among the first commercially viable ones. The flight plan is fairly simple: The White Knight would drop SpaceShipOne at an altitude of 15,2 km.
SpaceShipOne then climbs nearly vertically with 3-4G acceleration and with that speed the advanced hybrid engine would approximately last 65 seconds. SSO could reach a height of approximately 100 km before free-falling back to earth. Passengers could experience microgravity for about 3,5 minutes.
An upgraded version of the WK and SSO is the WK2 and SSO2. The difference between them lies in the capacity, size and the amount of time which the SSO2 is capable of staying above the atmosphere, which can be even 2,5 hours.
A project by the Japanese Rocket Society, this SSTO (Single stage to orbit) VTOL (Vertical take-off and landing) aircraft is designed to carry 50 passengers to up to 200 km. The aim of this project was to decrease space tourism fees for such a flight to around $10000, to make it more accessible.
The Thunderbird is a low cost fully reusable VTOL. It is an X-Prize (award for innovators) contender, and is designed to carry three people on sub-orbital flights into space.
A priority of its development was that it should only use only existing materials to minimize development cost. The airframe is the only exception, being an advanced and sophisticated model. The propulsion is provided by kerosin-powered LOX engines which can carry it to up to 100 km altitude. After the engines have burned out, it re-enters the atmosphere by using a steerable parasail. Reaction control is handled by independent cold gas thrusters.
Despite being a single stage vehicle, it is composed out of two separable units, a command module and the propulsion module. In addition, there is an emergency command module which can be detached if necessary.
The command module contains the cabin, life support and the reaction control system, the propulsion module on the other hand contains the fuel tanks, the engines and the landing gear.
Probably the Orion is the most important design which we can mention here. It is the craft which is meant substitute the Space Shuttle (scheduled for retirement in 2010).
The Orion is a design currently under development by NASA. Each Orion spacecraft will be able to carry a crew of four people and will be launched by the Ares I, launch vehicle also currently under development. Both Orion and Ares I are elements of NASA's plan (Project Constellation) to send human astronauts back to the Moon by 2020. They also intend to reach the Mars and several other destinations with the help of Orion. The International Space Station will be its first target if commercial orbital transportation will be unavailable at the time. The first Orion flight is scheduled at 2014 or 2015.