The Orion Multi-Purpose Crew Vehicle (MPCV) is a partially reusable crewed spacecraft used by NASA for the Artemis lunar exploration program. It consists of a crew module (CM), a space capsule built by Lockheed Martin, and is paired with a European Service Module (ESM) provided by the European Space Agency (ESA) and manufactured by Airbus Defence and Space. Orion supports a crew of four beyond low Earth orbit for up to 21 days undocked or up to six months when docked. It is equipped with a NASA Docking System port and glass cockpit displays. It is intended to be launched atop the Space Launch System (SLS) rocket with a tower-mounted launch escape system.
Orion was conceived in the early 2000s by Lockheed Martin as a proposal for the Crew Exploration Vehicle (CEV) to be used in NASA's Constellation program and was selected by NASA in 2006. After the cancellation of the Constellation program in 2010, Orion was extensively redesigned for use in NASA's Journey to Mars initiative; later named Moon to Mars. The SLS became Orion's primary launch vehicle, and the service module was replaced with a design based on ESA's Automated Transfer Vehicle.
three flight-worthy vehicles had been built along with several boilerplates and test articles. Three additional flight-worthy vehicles are under construction.
In May 2025, the second Trump administration proposed terminating the Orion spacecraft program after Artemis III. The One Big Beautiful Bill Act signed in July 2025 included a provision to fund procurement of Orion for Artemis IV and reuse in future missions.
Design
Orion is based on the configuration of the Apollo command and service module (CSM), with a larger diameter, updated thermal protection system, and modern avionics. It is designed for deep space missions supporting up to 21 days of active crew operations and up to six months of quiescent spacecraft operation. The Orion crew module launches with the European Service Module, a spacecraft adapter, and a launch abort system.
The Orion crew module (OCM) is a reusable capsule providing habitable volume, storage for consumables and research equipment, and an International Docking System Standard (IDSS) port for crew transfers. It is the only major spacecraft element that returns to Earth after each mission and is designed for refurbishment and reuse, with modular systems intended to support incremental upgrades over time.
Structure and manufacture The OCM is built of aluminum-lithium alloy and has a 57.5° frustum shape with a blunt spherical aft end, in diameter and in length, with a mass of about . The module provides approximately 50% more internal volume than the Apollo command module and is designed to carry four astronauts on Artemis missions. It is manufactured by Lockheed Martin, with the pressure vessel built at the Michoud Assembly Facility in New Orleans, Louisiana, and final assembly conducted at the Operations and Checkout Building at Kennedy Space Center in Florida.
Thermal protection After evaluation of thermal protection materials, NASA selected AVCOAT for the ablative heat shield. AVCOAT consists of silica fibers embedded in a resin within a honeycomb structure of fiberglass and phenolic resin. It was previously used on the Apollo missions and the Space Shuttle orbiter.
Crew systems and accommodations The OCM uses a glass cockpit with digital control systems derived in part from those used in the Boeing 787 Dreamliner. The commander and pilot are seated facing three main display screens and seven switch panels within arm's reach, which provide spacecraft status information and allow control of onboard systems. A cursor control device enables interaction with the display screens under high g-forces, when the crew can not easily reach out. The interface supports both routine operations and anomaly response through integrated electronic procedures and warning systems. Rotational and translational hand controllers enable the crew to manually adjust the spacecraft's orientation and movement.
The four crew seats are designed to accommodate a wide range of astronaut body sizes, from approximately the 1st to the 99th percentile, and are adjustable. For launch and re-entry, astronauts are positioned on their backs with knees bent at a 90-degree angle and feet secured in foot pans. Each seat incorporates a five-point harness, headrests, and shoulder and hip bolsters, with foot restraints that interface with crew footwear to limit movement. The seats include an impact attenuation system, which reduces loads during splashdown by allowing controlled motion along guide rails. Once in orbit, the foot pans on the commander and pilot seats are removed and stowed to increase cabin space, and a cargo net over the mission specialist seats provides storage for equipment and suit components.
The spacecraft operates with a mixed nitrogen/oxygen (/) atmosphere at either sea-level pressure () or a reduced pressure (). As of 2019, the Spacecraft Atmosphere Monitor was planned to be used in the OCM.
The OCM includes the compact Orion flywheel exercise device, which allows astronauts to perform aerobic and resistance exercises during flight using a cable-driven flywheel mechanism. The system was designed to meet the spacecraft's mass and volume constraints while also allowing for a wide range of exercises. Mounted below the side hatch, it also functions as a step for crew members entering or exiting the spacecraft.
The OCM includes a space toilet called the Universal Waste Management System (UWMS) inside a fully enclosed compartment for privacy that uses airflow to manage liquid and solid waste. Solid waste is stored in sealed containers, while treated liquid waste is vented overboard.
The potable water dispenser supplies water for rehydrating food, preparing drinks, and supporting medical needs in Orion. It connects to four pressurized tanks in the service module. A briefcase-style food warmer plugs into Orion's power utility panel for operation and allows the crew to heat food and beverages. It can be secured to cabin surfaces using Velcro when needed and stowed when not in use.
Launch and recovery
During launch, the spacecraft is equipped with a launch abort system (LAS), attached to the nose of the spacecraft. The spacecraft is covered by a fiberglass "Boost Protective Cover" that shields the crew module from aerodynamic and impact stresses during the first minutes of ascent.
The capsule is recovered by parachute-assisted water landing. The parachute system is derived from those used on Apollo spacecraft and Space Shuttle Solid Rocket Boosters and is constructed of Nomex.
European Service Module (ESM)
Launch Abort System (LAS)
In the event of an emergency on the launch pad or during ascent, the Launch Abort System (LAS) will separate the crew module from the launch vehicle using three solid rocket motors: an abort motor (AM), an attitude control motor (ACM), and a jettison motor (JM). The AM provides the thrust needed to accelerate the capsule, while the ACM is used to point the AM and the jettison motor separates the LAS from the crew capsule. On July 10, 2007, Orbital Sciences, the prime contractor for the LAS, awarded Alliant Techsystems (ATK) a $62.5 million sub-contract to "design, develop, produce, test and deliver the launch abort motor," which uses a "reverse flow" design. On July 9, 2008, NASA announced that ATK had completed construction of a vertical test stand at a facility in Promontory, Utah to test launch abort motors for the Orion spacecraft. Another long-time space motor contractor, Aerojet, was awarded the jettison motor design and development contract for the LAS. As of September 2008, Aerojet has, along with team members Orbital Sciences, Lockheed Martin and NASA, successfully demonstrated two full-scale test firings of the jettison motor. This motor is used on every flight, as it separates the LAS from the vehicle after both a successful launch and a launch abort.
Performance With the announcement in 2019 of the intent to procure a Human Landing System for Artemis missions, NASA provided Orion mass and propulsion capability values. After separation from the SLS upper stage, the Orion is expected to have a mass of and be capable of performing maneuvers requiring up to of delta-v.
History
The Orion MPCV was announced by NASA on May 24, 2011. Its design is based on the Crew Exploration Vehicle from the canceled Constellation program, which had been a 2006 NASA contract award to Lockheed Martin. The command module is being built by Lockheed Martin at the Michoud Assembly Facility, while the Orion service module is being built by Airbus Defence and Space in Bremen with funding from the European Space Agency. The CM's first uncrewed test flight (EFT-1) was launched without the EUS atop a Delta IV Heavy rocket on December 5, 2014, and lasted 4 hours and 24 minutes before landing at its target in the Pacific Ocean.
Orion was primarily designed by Lockheed Martin Space Systems in Littleton, Colorado, with former Space Shuttle engineer Julie Kramer White at NASA as Orion's chief engineer.
On November 30, 2020, it was reported that NASA and Lockheed Martin had found a failure with a component in one of the Orion spacecraft's power data units but NASA later clarified that it did not expect the issue to affect the Artemis I launch date.
Funding history and planning NASA has spent $25.6 billion on Orion development from 2006 through 2025, in nominal dollars. This is equivalent to $33.6 billion in 2026 dollars using the NASA New Start Inflation Indices."NASA FY22 Inflation Tables – to be used in FY23 Archived 31 October 2022 at the Wayback Machine" (Excel). NASA. Retrieved October 31, 2022. This article incorporates text from this source, which is in the public domain.
Fiscal year Funding Source In Nominal (millions) In 2026 (millions) 2006 $839.2 $1,367.9 Crew Exploration Vehicle (CEV) 2007 $714.5 $1,121.4 CEV 2008 $1,174.1 $1,779.3 CEV 2009 $1,747.9 $2,599.4 CEV 2010 $1,640.0 $2,406.0 CEV 2011 $1,196.0 $1,726.8 MPCV 2012 $1,200.0 $1,714.3 Orion MPCV 2013 $1,138.0 $1,567.6 Orion MPCV 2014 $1,197.0 $1,652.3 Orion Program 2015 $1,190.2 $1,610.5 Orion Program 2016 $1,270.0 $1,697.9 Orion Program 2017 $1,350.0 $1,767.2 Orion2018 $1,350.0 $1,723.5 Orion 2019 $1,350.0 $1,690.9 Orion 2020 $1,406.7 $1,723.7 Orion 2021 $1,403.7 $1,657.3 Orion"National Aeronautics and Space Administration FY 2021 Spending Plan" (PDF). NASA. Archived from the original 31 October 2022. Retrieved 31 October 2022 This article incorporates text from this source, which is in the public domain. 2022 $1,401.7 $1,565.5 Orion"Consolidated Appropriations Act, 2022" (PDF). Retrieved 31 October 2022. p.212. Archived from the original on 31 October 2022. This article incorporates text from this source, which is in the public domain. 2023 $1,315.1 $1,411.1 FY 2023 Op Plan in FY 2025 Budget Request 2024 $1,283.7 $1,343.1 FY 2024 Op Plan in FY 2026 Budget Request2025$1,431.4$1,463.9FY 2025 Spend Plan Total $25,575.0 $33,589.7
Excluded from the prior Orion costs are: Most costs "for production, operations, or sustainment of additional crew capsules, despite plans to use and possibly enhance this capsule after 2021"; production and operations contracts were awarded going into fiscal year 2020. The costs of Orion's service module, provided by the European Space Agency. (The European Service Module.)