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Orion (spacecraft)

Orion is a spacecraft design that is being developed by the United States space agency NASA. When completed, each Orion spacecraft will carry a crew of up to six astronauts. Along with Orion, the Ares I launch vehicle is also being developed. Orion and Ares I are both part of NASA’s Project Constellation. The project should be complete in 2010, when NASA wants to start planning on sending human explorers back to the Moon, and eventually Mars and other celestial bodies in the Solar System. Lockheed Martin won the contract to design and build Orion.

Orion will be launched from Launch Complex 39 at Kennedy Space Center, which is the same launch complex that currently launches the space shuttle. NASA will use Orion for its human space missions after the last shuttle orbiter is retired in 2010. The first Orion flight with human astronauts is projected for the year 2015. Flights will first carry crew to the International Space Station; missions to the Moon and Mars will follow.

President George W. Bush announced the Orion spacecraft development on January 14, 2004. It was originally called the Crew Exploration Vehicle (CEV). The proposal to create Orion came in part due to the Space Shuttle Columbia accident and the subsequent findings by the Columbia Accident Investigation Board, as well as the government’s review of the space program. The Orion replaced the Orbital Space Plane, which was originally proposed after the failure of the Lockheed Martin X-33 program, which was developed to replace the space shuttle. The Orion spacecraft should not be confused with Project Orion, which took place in the 1950′s. Project Orion dealt with nuclear propulsion. The Orion spacecraft will use non-nuclear propulsion. The name of the Orion spacecraft is derived from the constellation of Orion, and also from the name of the Apollo 16 Lunar Module that carried astronauts to the surface of the Moon in April 1972.

The Orion spacecraft will consist of two main parts: a conical Crew Module (CM), and a cylindrical Service Module (SM) which holds the spacecraft’s propulsion system. The system is much like the Apollo Command and Service Modules used between 1967 and 1975, but will include advanced systems derived from the space shuttle program. The Orion CM will hold 4 to 6 crew members, compared to a maximum of three in the Apollo CM, and seven in the space shuttle. Some of the advanced tools and technologies found in the Orion spacecraft will include: A digital “glass cockpit” control system, an auto dock feature, improved waste-management facilities, a nitrogen/oxygen atmosphere, and more advanced computers than seen in any other manned spacecraft.

The Orion will be constructed for use in multiple missions. NASA wants to be able to use the modules for up to ten flights. The modules will be constructed of an aluminium/lithium alloy similar to the material used on the external tank of the shuttle and Delta IV and Atlas V rockets. This alloy is durable, yet it will make the Orion much lighter than both of its Apollo and shuttle predecessors. The CM will be covered in Nomex thermal protection blankets. A new Low Impact Docking System will be used to allow the Orion to dock with and service the International Space Station, and to mate with other Project Constellation vehicles.

The Orion CM will be 16.47 feet in diameter and 10.83 feet in length. It will have a mass of about 19,000 pounds. It will have more than 2.5 times the volume of the similar Apollo modules of the 60s and 70s. The main propulsion system of Orion will be an Aerojet AJ-10 rocket engine. It will be powered by hypergolic fuels (mixture of fuel and an oxidizer that ignites spontaneously upon contact) that will be kept in helium pressured fuel cells. The thrusters and controls, along with the main propulsion will be pressure-fed. A pair of LOX tanks will provide crew with breathing air at sea-level pressure, and smaller surge tanks that provide life support during reentry and touchdown. Lithium hydroxide cartridges will recycle the air within the spacecraft by cleansing the air of carbon dioxide that is exhaled, and then adding fresh oxygen/nitrogen back into the system. With the introduction of solar panels, the service module will have an onboard water tank which will provide drinking water for the crew, and cooling water for the spacecraft’s electronics. The Orion will also have an onboard recycling system that will convert waste water and urine into both drinking and cooling water.

The Orion SM will be cylindrical in shape. It will have a diameter of 16.5 feet and length of 15.68 feet (including the thruster). With the solar panels extended, the span will be about 55 feet. Empty mass of the SM will be around 8,000 pounds. With fuel capacity at its maximum, the mass will be 18,000 pounds.

In the event of an emergency on the launch pad or during ascent, a launch escape system will be implemented. The Launch Abort System (LAS) will separate the CM from the launch vehicle using a solid rocket-powered launch abort motor. This abort motor is more powerful than the actual booster that launched John Glenn into orbit in 1962. Alliant Techsystems won a contract to design and develop the abort motor at a cost of $62.5 million. Alliant Techsystems has the prime contract for the Ares I rocket, and intends to use the innovation behind that rocket to create the abort motor. The launch abort motor will be important as it is supposed to pull the LAS tower away from the spacecraft after a successful launch. It will function in the same manner for an abort scenario. There are other ideas floating around by NASA that may be implemented to help protect the safety of the crew in any scenario. There have been several revisions and updates since the launch of the Orion program and the Constellation Project.

Several successful test launches have been done by Alliant Techsystems for its LAS. The abort motor will provide 500,000 pounds of thrust in an emergency on the launch pad or during the first 300,000 feet of the rocket’s climb into orbit. The tests are important to revise any problems that may affect the potential launch of an actual emergency. The test firing of the abort motor on November 20, 2008 was the largest test of this type that has ever been tested on this scale. This and other tests are a preparation for the next major milestone, a full-size test firing scheduled for the spring of 2009. Many other tests are also being held between 2007 and 2011 to prepare for the actual launch of the Constellation Project’s Orion and Ares I missions.

Three stages are planned for the Orion program. Stage I will be used for unmanned lunar landings which will begin when the space shuttle program is retired in 2010. Stage II will be implemented for interplanetary flight, sending manned modules to the orbits of the Moon, Near Earth Objects, and Mars and its Moons, as well as other points in space. Stage II is expected to begin around 2018. Stage III is for manned spaceflights to the Moon and possibly Mars where landings could occur. The landings could begin in 2020. Although the Orion program is still early in the development stages and it remains to be seen what form it may actually take, NASA is taking the appropriate steps needed for the implementation of stage I of the project. The current plan does not allow for lunar landings as early as 2015, as suggested by the George W. Bush vision, but does permit an early Mars landing in 2020.

Funding for the Orion spacecraft and Project Constellation could top $15 billion through 2013. The initial 5 year funding for 2005-2009 was estimated at around 6.6 billion dollars. Although full funding has been acquired for the contracts for the development of the Orion and Ares, further funding might be difficult. There are talks of either obtaining a special supplemental from Congress to pay for the extra costs, or involving private industry in development and operations. The total funding of Project Constellation through 2025 is estimated to reach $210 billion.

Orion spacecraft


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