NASA has stacked the Orion spacecraft atop the Space Launch System (SLS) rocket ahead of crucial pre-flight tests in the coming weeks. The capsule being prepared for Artemis 2 mission will take four astronauts on a journey to the lunar orbit, marking humanity’s return to deep space after 54 years. Notably, the astronauts will return in 10 days without landing on the lunar surface.
Orion has been tested once before during Artemis 1 in 2022, but the stakes are higher this time because there will be humans aboard the spacecraft.
Artemis II is stacked, communication systems have been tested, and now we are gearing up for a launch day dress rehearsal.
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American Astronauts Reid Wiseman, Christina Koch, Victor Glover and Canada’s Jeremy Hansen have been tasked with testing Orion’s critical components in a deep space environment and proving its life support systems are capable of supporting long-duration missions.
According to NASA, Orion, named Integrity for Artemis 2, is capable of supporting a crew of four for 21 days without docking with another spacecraft, and Artemis 2 will prove its readiness for a manned mission.
Orion inside out
The Orion spacecraft is composed of a Crew Module, built by Lockheed Martin, and the European Service Module or ESM, built by the European Space Agency (ESA). When integrated, Orion stands 26.5 feet (8.1 metres) tall and has a mass of 26,000 kg with fuel.
The Crew Module stands 16.5 feet (5 metres) tall and this is where the four astronauts will stay during the course of their mission. It is equipped with three 13-inch touchscreen displays, manual flight control panels, four panoramic windows, thermal control, systems for removing carbon dioxide and moisture, storage system for breathable air and water, and stowage lockers on the floor in case the crew needs to shield itself from a radiation event.
Orion is also fitted with an advanced compact toilet, with improved design that makes its use in space easier for both men and women. The crew will also have access to built-in exercise device for both aerobic and strength training.
The spacecraft’s lifeline is the ESM that will supply it with electricity, propulsion, thermal control, oxygen, nitrogen and water. It has 33 engines, including one main and 24 reaction control thrusters that are used to steer and control Orion while in orbit. There are also eight auxiliary engines to execute translational maneuvers, essentially acting as a backup to the main engine. The ESM also has massive solar arrays, with 15,000 solar cells, spanning approximately 19 metres which can generate up to 11 kW of electricity.
At its base, Orion is covered with the world’s largest heat shield measuring 16.5 feet in diameter. NASA says it is designed to survive atmospheric re-entry at 40,233 km per hour and endure temperatures up to 2,760°C.
Shortly before re-entry, the Crew Module will separate from the Service Module for a splashdown using a system of 11 parachutes that will deploy sequentially.
Concerns regarding Orion
Artemis 1 exposed a few flaws in Orion’s design. The spacecraft went offline multiple times while in space, causing communication outages. NASA has reportedly made software and antenna upgrades to fix the problem. Besides, the heatshield also got eroded more than expected, prompting NASA to redesign it and make it more durable.
When is Artemis 2 launching?
NASA has said that Artemis 2 will launch no later than April 2026 and the agency is currently targeting a launch window in February next year. The Orion spacecraft has been stacked atop the SLS rocket and both components will undergo several rounds of key tests in the following weeks with the astronauts’ participation. The rocket will then be rolled out to the launch pad at NASA’s Kennedy Space Center for a wet dress rehearsal, wherein it will be loaded with propellant and mission teams will conduct a full launch countdown as an exercise.
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