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Orion is a manned spacecraft currently under development by the United States. Prior to receiving its current name Orion was known as the Crew Exploration Vehicle (CEV). The new spacecraft will replace the current Space Shuttle fleet after the shuttles are retired in 2010, and will be launched from Kennedy Space Center on the new Ares I crew launch vehicle. Orion will initially handle logistic flights to the International Space Station, but will be a key component for future missions to the Moon and Mars after 2015. Together with the Earth Departure Stage (EDS), the Lunar Surface Access Module (LSAM), and the Ares I and Ares V Shuttle Derived Launch Vehicles (SDLV), Orion is one of the elements of NASA's Project Constellation. • Origin The proposal to create the Orion spacecraft is partly a reaction to the Space Shuttle Columbia disaster, the subsequent findings and report by the Columbia Accident Investigation Board (CAIB), and the White House's review of the American space program. The Orion spacecraft effectively replaced the conceptual Orbital Space Plane (OSP), which itself was proposed after the failure of the Lockheed Martin X-33 program to produce a replacement for the shuttle. On January 14 2004, President George W. Bush announced the Orion spacecraft, then known as the "Crew Exploration Vehicle," as part of the Vision for Space Exploration: "Our second goal is to develop and test a new spacecraft, the Crew Exploration Vehicle, by 2008, and to conduct the first manned mission no later than 2014. The Crew Exploration Vehicle will be capable of ferrying astronauts and scientists to the Space Station after the shuttle is retired. But the main purpose of this spacecraft will be to carry astronauts beyond our orbit to other worlds. This will be the first spacecraft of its kind since the Apollo Command Module."• Design The Orion Crew & Service Module (CSM) stack consists of two main parts: a conical Crew Module (CM), and a cylindrical Service Module (SM) which will hold the spacecraft's propulsion system and expendable onboard supplies. Both are based heavily on the Apollo Command & Service Modules (Apollo CSM) flown between 1967 and 1975, but include advances derived from the Space Shuttle program. "Going with known technology and known solutions lowers the risk," according to Neil Woodward, director of the integration office in the Exploration Systems Mission Directorate.• Crew Module (CM) The Orion CM is similar in shape to Apollo Command Module (a 70° cone) and is capable of holding four to six crew members (in comparison with a maximum of three in the smaller Apollo Command Module, although a five-man version for the never-flown Skylab Rescue was produced). Although superficially resembling the 1960s-era Apollo, Orion's CM will boast significantly improved technology, including, but not limited to: An important feature that will be introduced in the Orion CM is a new system employing a combination of parachutes and airbags for capsule recovery. This will allow retrieval of the Orion CM on land, like the Russian Soyuz and Chinese Shenzhou descent module, and eliminate the expensive naval recovery fleet employed on all Mercury, Gemini, and Apollo flights. The CM will also have the capability of water recovery, but it would be limited to in-flight aborts in which the launch escape system must be employed to pull the CM away from a malfunctioning Ares I rocket, or in the case of a Gemini 8-type emergency if the reentry thrusters are activated. In the case of a launch abort, NASA will use either the M/V Freedom Star or M/V Liberty Star in conjunction with U.S. Coast Guard personnel who will then retrieve the capsule, while an emergency splashdown after launch will require the observance of the Outer Space Treaty signed in 1967. Another feature will be the partial reusability of the Orion CM, which would be capable of being reused for up to ten flights, allowing NASA to build a fleet of both manned and unmanned Orion CMs. Both the CM and SM will be constructed of an aluminum/lithium (Al/Li) alloy that is as strong as the aircraft aluminum used on the Shuttle Orbiter's skin, but will make the spacecraft lighter than both its Apollo and Shuttle predecessors. The CM itself will be covered in the same nomex felt-like thermal protection blankets used on non-critical parts on the Shuttle (such as the payload bay doors) while the Thermal Protection System (TPS) will be made of a derivative of the Phenolic Impregnated Carbon Ablator (PICA) heat shield previously developed for the Stardust return mission. The heat shield, attached to the CM using an eight-point attachment system, will drop off after reentry to expose the airbags. The recovery parachutes, also reusable, will be based on the parachutes used on both the Apollo spacecraft and will also use the same nomex cloth for construction. To allow the Orion spacecraft to service the International Space Station (ISS), it will use a simplified version of the Russian-developed universal docking ring currently in use on the Shuttle fleet and based on the earlier system used on the Apollo-Soyuz Test Project. Both the spacecraft and docking adapter will employ a Launch Escape System (LES) like that used in Mercury and Apollo, along with an Apollo-derived fiberglass "Boost Protective Cover," to protect the Orion CM during ascent. The Orion CM is projected to be around 5 meters (16.5 feet) in diameter, with a mass of about 25 tonnes. It is to be built by the Lockheed Martin Corporation. * It will have more than 2.5 times the volume of an Apollo capsule and can carry between four to six astronauts. * Service Module (SM) Like its Apollo predecessor, the Orion service module has a cylindrical shape, but the new Orion SM will be larger, shorter, and lighter. It too would be constructed from the same Al-Li alloy as the Orion CM, and will feature a pair of deployable circular or rectangular solar panels (a final decision on their design has not yet been made), eliminating the need to carry malfunction-prone fuel cells and the associated hardware (mainly tanks containing liquid hydrogen LH2) needed for their operation. The spacecraft main propulsion system is a Delta II upper stage engine using hypergolic propellants (nitrogen tetroxide and monomethyl hydrazine) drawn from spherical, helium-pressurized titanium tanks. The SM Reaction Control System (RCS -- the spacecraft's maneuvering thrusters) will also be pressure-fed, and will use the same propellants. NASA believes the SM RCS would be able to act as a backup for a trans-Earth injection (TEI) burn in case the main SM engine fails. The SM's twin spherical "slush" LOX tanks and a single tank of liquid nitrogen (LN2) will provide the crew with breathing air during the majority of the mission, while a "surge tank" located in the Orion CM itself will provide the crew with 2 to 4 hours (depending upon the number of crew members) of the same breathing air after SM jettison. Lithium hydroxide (LiOH) cartridges will recycle the spacecraft's environmental system by "scrubbing" the carbon dioxide (CO2) exhaled by the astronauts from ship's air and adding fresh oxygen and nitrogen, which is then cycled back out into the system loop. Because of the elimination of the fuel cells and LH2 tanks, a large tank of potable water will be carried in both the CM and SM that will both provide drinking water for the astronauts and (mixed with glycol) cooling water for the electronics. A system identical to that used in the ISS will allow the astronauts to recycle both waste water and urine into glycol-mixed cooling water for the electronics. The SM also mounts the spacecraft's waste heat management system (its radiators) and the aforementioned solar panels. These panels, along with backup batteries located in the Orion CM, will provide a total of 28 V (dc) in-flight power to the ship's systems. July 2006 design revisions In late July of 2006 NASA's second design review resulted in major changes to the spacecraft design. * Originally, NASA wanted to use liquid methane (LCH4) as the SM fuel, as it could be "mined" (in situ) on the Moon, Mars, and other methane-rich bodies, but due to the infancy of oxygen/methane-powered rocket technologies and the need to launch the Orion by 2012, the switch to hypergolic propellants was mandated in late July 2006. This switch will allow NASA to man-rate the Orion and Ares I stack by no later than 2011 , and eliminate a possible delay between the Shuttle's retirement in 2010 and the first manned Orion flight scheduled for 2012 . Criticism Hypergolics The switch to hypergolic fuels has not been welcomed by some critics of the Orion program. Unlike LOX/LH2, LOX/RP-1, or even LOX/ethanol fuel mixtures, which require an ignition source to burn, hypergolic fuels spontaneously ignite when the components are mixed together in the rocket's combustion chamber. This allows for the reliable storage and ignition of such fuels (as used on the Titan II ICBM rocket, and later on both the Apollo Service Module and Apollo Lunar Module, Titan III rocket, and Titan IV-Centaur rocket), but provides a less-than-ideal thrust as compared to LOX/LH2 or LOX/LCH4. In addition, hypergolics are very corrosive and hazardous when humans are exposed. An incident during the landing phase on the Apollo-Soyuz Test Project flight exposed the crew to fumes, causing a form of chemical-induced pneumonia, and nearly killing one crew member (his life was saved by another astronaut when he placed an oxygen mask over his face). Another hazard occurred with the breakup of Columbia in 2003, when parts of the orbiter were exposed to the chemicals, causing chemical burns to those who handled the Shuttle debris without any protection. Even under normal conditions, Shuttle landing party crews must wear environmental "SCAPE" suits right after the Orbiter comes to a complete stop until the system is safed and purged before flight surgeons and technicians wearing white surgical smocks can enter the Orbiter to retrieve the crew. The combustion of cryogenic oxygen and hydrogen, on the other hand, produces pure water, while LCH4, can be produced, shipped, and stored in the same fashon as commercial-use liquified natural gas (LNG). Despite the switch to hypergolic fuels for the early-model ("Block I") Orion, experts think that LCH4 propulsion will be utilized on later Orion variants, especially those intended for use on Mars; in some Martian mission models, fuel for Orion-derived ships could be produced on the Martian surface by means of equipment utilizing the Sabatier reaction. By "distilling" the thin carbon dioxide (CO2) atmosphere of Mars into LCH4. By using this fashion, the crew of an Orion Mars mission could vastly decrease the need to carry fuel for their return trip, thus increasing the amount of equipment and supplies they could carry for use in exploring the red planet. (See also the Mars Direct mission proposal). Acquisition strategy The Space Frontier Foundation has asserted that the $3.9 billion initial phase of the Orion contract essentially duplicates the functionality of NASA's $500 million Commercial Orbital Transportation Services program.• Exploration Systems Architecture Study Competition The Draft Statement of Work for the CEV was issued by NASA on December 9, 2004, and slightly more than one month later, on January 21, 2005, NASA issued a Draft Request For Proposal. The Final RFP was issued on March 1, 2005,• According to an Aerospace Daily & Defense Report summary of a NASA document explaining the rationale for the contract award, the Lockheed Martin proposal won on the basis of a superior technical approach, lower and more realistic cost estimates, and exceptional performance on Phase I of the CEV program.• Lockheed Martin plans to manufacture the manned spacecraft at facilities in Texas, Louisiana, and Florida.• The program manager is Cleon Lacefield. Proposals Original designs Lockheed's proposed craft was a small shuttle-shaped lifting-body design, big enough for six astronauts and their equipment. Its airplane-shaped design made it easier to navigate during high-speed returns to Earth than the capsule-shaped vehicles of the past, according to Lockheed Martin. According to the French daily Le Figaro and the publication Aviation Week and Space Technology, EADS SPACE Transportation would be in charge of the design and construction of the associated Mission Module. The head of the Lockheed team was Cleon Lacefield. The Lockheed Martin design was quite similar to their OSP design, but has some slight changes, mainly the presence of the mission module *. The Lockheed Martin CEV design included several modules in the LEO (low earth orbit) and manned lunar versions of the spacecraft, plus an abort system. The abort system was an escape tower like that used in the Mercury, Apollo, Soyuz, and Shenzhou craft (Gemini, along with the Space Shuttles Enterprise and Columbia until STS-4 used ejection seats). It would be capable of an abort during any part of the ascent phase of the mission. The crew would sit in the Rescue Module (RM) during launch. According to the publication Aviation Week and Space Technology, the RM would have an outer heat shield of reinforced carbon-carbon and a redundant layer of felt reusable surface insulation underneath in case of RCC failure. The RM comprised the top half of the Crew Module (CM), which comprised the RM and the rest of the lifting-body structure. The CM included living space for four crewmembers. In an emergency the RM separates from the rest of the CM. The RM would seat up to six crewmembers, with two to a row, and the CM has living space and provisions for four astronauts for 5–7 days. EVAs could be conducted from the CM, which could land on land or water and could be reused 5–10 times.* The mission module would be added to the bottom of the CEV for a lunar mission, and would be able to hold extra consumables and provide extra space for a mission of lunar duration. It would also provide extra power and communications capabilities, and include a docking port for the LSAM. On the bottom of the lunar CEV stack would be the Propulsion or Trans-Earth Injection Module would provide for return to Earth from the Moon. It would probably incorporate (according to Aviation Week) 2 Pratt & Whitney RL-10 engines. Together, the RM/CM, MM, and TEIM made up the Lockheed Martin lunar stack. The original idea was to launch the CM, MM, and TEIM on three separate EELVs, with one component in each launch. This vehicle would need additional modules to reach lunar orbit and to land on the Moon. However, this plan was to be altered according to the CFI (Call for Improvements), described below. Unlike the well-publicized Lockheed Martin CEV design, virtually no information was publicly available on the Boeing/Northrop Grumman CEV design. However, it is instructive to note that most publicly released Boeing designs for the cancelled Orbital Space Plane resembled the Apollo capsule. Given that Lockheed Martin's CEV design was in many ways a derivative of their OSP, it was possible that the Boeing CEV is a capsule rather than a lifting body or plane design. * Changes to original bids Sean O'Keefe's strategy would have seen the CEV development in two distinct stages, or Phases. Phase I would have involved the design of the CEV and a demonstration by the potential contractors that they could safely and affordably develop the vehicle. Phase I would have run from bid submissions in 2005 to FAST and downselect to one contractor. Phase II would have begun after FAST and involved final design and construction of the CEV. However, this schedule was unacceptably slow to Mike Griffin, and the plan was changed such that NASA will issue a "Call for Improvements" (CFI) after the release of the ESAS for Lockheed Martin and Boeing to submit Phase II proposals.* NASA chose Lockheed Martin's consortium as the winning consortium on August 31, 2006.* Therefore, the CEV bids submitted and described above are not necessarily representative of the final CEV design, as they will be changed in accordance with the CFI and any findings of the ESAS that are put into the CFI. Schedule NASA hopes to follow this schedule in development of the CEV: It has been rumored that the ESAS will support a phased retirement of the Space Shuttle, which would begin by retiring one orbiter (probably Atlantis), as early as 2008. Under this plan, Discovery would likely be retired in late 2009, followed by the retirement of Endeavour prior to September 30, 2010 (the last day of fiscal year (FY) 2010). In the meantime, NASA engineers would work to upgrade the current launch facilities to work with the next generation shuttle-derived launch vehicles. * Such a plan would allow lunar mission development to begin much earlier than currently planned, as additional funding will be available earlier. Possibilities for future CEV development After the replacement of Sean O'Keefe, NASA's procurement schedule and strategy has completely changed, as described above. In July 2004, before he was named NASA administrator, Michael Griffin participated in a study called "Extending Human Presence Into the Solar System"* for The Planetary Society, as a co-team leader. The study offers a strategy for carrying out Project Constellation in an affordable and achievable manner. Since Griffin was one of the leaders of the study, it can be assumed that he agrees with its conclusions, and it is therefore instructive to review the study to gain insight into possible future developments regarding the CEV. Indeed, as described below, the actions he has taken thus far as administrator support the goals of the plan. According to the executive summary, the study is built around "a staged approach to human exploration beyond low Earth orbit (LEO)." * It recommends that Project Constellation be carried out in three distinct phases, called "Stages." These are: Stage I Rather than designing a CEV solely for the earliest lunar landing possible, the report recommends developing the CEV in two Blocks. The Block I CEV would be suitable for LEO missions only and would be developed as quickly as possible to avoid the gap between the currently scheduled Shuttle retirement in 2010 and CEV flights starting in 2014. It would carry a crew of 4–6 astronauts. The report recommends the development of a shuttle-derived CEV launch vehicle based on the "Shuttle Solid Rocket Motor with a new liquid propellant upper stage" * for CEV launch, rather than man-rating an EELV. This approach would allow the advantages of using a proven, man-rated design (the Solid Rocket Motor), plus the ability to continue using Shuttle infrastructure to support CEV operations. Indeed, as described above, the upcoming Exploration Systems Architecture Study is thought to contain an endorsement of exactly this option — the construction of an SRM-based SDLV, plus a heavy-lift launch vehicle derived from the Shuttle, in addition to options for expediting CEV development to permit earlier manned flight. * Therefore, the idea that the Planetary Society report could shed light on future CEV development is supported by these new developments. In other words, the very recommendations contained in the report for the beginning of Stage I — namely, the expedited CEV development and the SRM-derived launch vehicle — appear to have materialized. Under the rest of Stage I, the Shuttle would be retired as soon as possible after completing the "U.S. Core Complete" configuration of the International Space Station, an option that also appears to have gained support within NASA and the Bush administration *. The report makes no specific mention of a manned Hubble Space Telescope servicing mission, although Administrator Griffin has instructed Hubble managers at NASA Goddard Space Flight Center to make preparations for such a mission *, and the report refers to Hubble as "world-class astronomy". * The report suggests the use of expendable launchers, either foreign vehicles such as the Ariane and Proton, or a new Shuttle-derived, heavy-lift launch vehicle to complete the ISS after Shuttle retirement. The Block I CEV could also act as an ISS Crew Return Vehicle, allowing crews of more than three to be supported. Stage I is to be implemented by 2010. Stage II Under Stage II, a new Block II CEV would be developed, suitable for interplanetary flight. The report states that the new CEV should keep the same mold lines as the Block I, making the selection of an appropriate Block I CEV extremely important to the successful implementation of the plan. The report states that the Block II CEV would need to have capability to conduct interplanetary cruises of at least several months in duration. It suggests the development of other modules, specifically modules called "Hab," "Lab," "Propulsion," and "Consumables" to support longer-duration flights. The use of ISS module derivatives for the Hab and Lab modules is suggested but not explicitly endorsed. Four destinations are suggested for CEV exploration in Stage II. They are (probably, although not necessarily) in the order that they would be visited: The goal would be to conduct flights to each of these destinations but without a human-rated lander for the Moon and Mars. The use of SEL2 is described as important to demonstrate the capability of servicing future space telescopes (such as the James Webb Space Telescope) there and also for staging interplanetary flights. After the flights to SEL2, a flight to a NEO could be attempted; due to its extremely low surface gravity a landing module would not be needed and the astronauts could "walk" on it with MMU-like equipment. Finally, a mission to orbit Mars and possibly land on its moons is suggested. All these flights would be accomplished with one CEV design supported by the various modules, as necessary. Stage II would take place from about 2015 onward. However, according to the current descriptions of the ESAS, a landing on the Moon appears to be the first priority of Project Constellation and will occur by 2018 *. Stage III In Stage III, human-rated landers are developed to allow landings on both the Moon and Mars. Since the Block II CEV should be capable of flights to both these destinations, lunar and Mars landings could begin simultaneously, with the experience gained from exploring the four destinations referenced in Stage II. These landings would begin in 2020. Summary Although Orion development is still in an extremely early stage and it remains to be seen what form it will finally take, NASA is apparently taking exactly the steps recommended for the implementation of Stage I of the report. Therefore it is likely that the three-stage plan suggested in this report will be the plan for the actual Project Constellation. Although it appears that the plan will not be followed exactly, it is possible that elements of it will still be used as a baseline for Constellation exploration strategies (for example, Stage I appears to have become a NASA strategy). The plan does not allow for lunar landings as early as 2015, as suggested in the Bush vision, but does permit an early Mars landing in 2020, contemporaneous with lunar landings by that date. Building 9 at the Johnson Space Center in Houston, Texas contains a full-scale mock-up simulator of the Orion "capsule." As of July 26, 2006, internal components were being fitted. Funding President Bush's budget request for Fiscal Year 2005 included: "$428 million for Project Constellation ($6.6 billion over five years) to develop a new crew exploration vehicle." The budget for FY2005 was confirmed by the Congress in November 2004 with full funding for the CEV. The FY2006 budget request includes $753 million for continuing development of the CEV. As of 2005 the total development costs of the CEV are estimated at $ 15 billion. * Lockheed Martin's contract for the initial "Schedule A" part of the Orion project, awarded on August 31, 2006 and running through 2013, is worth $3.9 billion. Additional development options in the "Schedule B" part of the contract could be worth up to another $3.5 billion. * Although to date the exploration systems have received full funding and a House endorsement*, there is a possibility that rising Shuttle return to flight costs will make funding of CEV development extremely difficult. There has been discussion of either obtaining a special supplemental from Congress to pay for the extra Shuttle costs, or of involving private industry in CEV development and operations. * The total funding of Project Constellation through 2025, inflation-adjusted and without any other increases to NASA's budget, is estimated at $210 billion; the ESAS estimates the cost of the program through that date at being only $7 billion more, at $217 billion *. This cost may in fact end up lower as it includes developing new engines for the EDS instead of the newer idea of using J-2 derivatives*. Nomenclature In June 2006 the NASA assigned two "notional" names, Altair and Artemis, to the CSM and LSAM spacecraft. However, on 20 July, 2006, it was reported that the NASA had applied for trademark protection for the name "Orion" as both the name of the CEV spacecraft as a whole and as the name of its overall project to return to the moon. Astronaut Jeff Williams accidentally confirmed this name publicly and prematurely in a NASA communications blunder from the International Space Station on 22 August, 2006.•. In October 2006 NASA announced the official name "Artemis" for the LSAM spacecraft. Further revisions in nomenclature by NASA are possible before the launch of the first Orion mission. Orion Nomenclature (October 2006) See also | |||||||
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