Artemis III: NASA engineers explain how the Blue Moon and Starship landers will be tested before the 2028 Moon landing

Two test vehicles, one 16 metres tall and one about 52 metres, will dock with the Orion spacecraft in orbit around the Earth in 2027, a step before the first landing of astronauts on the Moon that NASA plans for 2028. They are test versions of the lunar landers of Blue Origin and SpaceX, the vehicles that will take astronauts from lunar orbit down to the surface. Two NASA engineers explained how the test will work in episode 443 of the Johnson Space Center’s “Houston We Have a Podcast”, published on Friday, October 30. The conversation was recorded on August 10, 2026.

Kent Criswell is lead systems engineer for Blue Origin’s lander in NASA’s Human Landing System programme, and Reid Ruggles has the same role for SpaceX’s Starship. The Artemis III mission will not reach the Moon. NASA has announced a 14-day flight in low Earth orbit with astronauts Randy Bresnik, Frank Rubio and Andre Douglas and ESA’s Luca Parmitano, with three spacecraft on three different rockets, as we wrote in our report on the test of the landers around the Earth.

A strict launch order

The order of launches is strict. Blue Origin’s test vehicle goes up first, into a circular orbit of about 439 kilometres (273 miles), and is checked to be in good condition before the crew launches. A few days later Orion leaves on the SLS rocket, and Starship launches last. Ruggles notes that coordinating three launches is in some respects harder than the landing missions, where there will be a single lander. In low orbit, however, there are more launch opportunities, since orbits are designed with repeating ground tracks.

The two test vehicles differ greatly. Blue Moon Mark 2 is 16 metres (52 feet) tall, with a crew cabin, landing legs and liquid-hydrogen and liquid-oxygen engines. Criswell compares it with the Apollo lunar module, which stood 7 metres (23 feet). It is carried as cargo on the New Glenn rocket and released in orbit. SpaceX’s Starship reaches about 52 metres (170 feet) in height and 9 metres (30 feet) in diameter, acts as the rocket’s second stage and is based on the V3 upper stage that already flies. Its cabin has a volume of about 620 cubic metres (22,000 cubic feet), roughly half the internal volume of the International Space Station, according to Ruggles, sits at the top and connects to the ground by an elevator.

Neither is a complete lander. As Ruggles explains, a test vehicle includes the riskiest systems so that data can be collected in a real environment. Starship will carry a docking adapter and a nosecone at the top to join Orion. Blue Origin’s Mark 2-D, the development version, has almost the same cabin as the lander but not the BE-7 lunar engine, and will use its thrusters to hold its attitude as the target. Orion will be the “chaser” that approaches in both cases. After docking with Blue Origin’s test vehicle the astronauts will spend about two days inside and check the life-support system. They will not enter Starship, and that docking will last up to two hours.

Docking is the hardest part

Approach and docking are the hardest point. Criswell stresses that Orion must see the target even in Earth’s shadow. Ruggles adds that lidar sensors and optical tracking “read” the shiny stainless steel of Starship differently from a white AZ-93-type paint, and that only in orbit will it be clear how Orion’s thrusters affect the other vehicle. There is also a thermal problem: light reflected from the Earth adds heat, sunlight and darkness alternate about every 45 minutes, and Orion, designed for deep space, must keep its tail toward the Sun.

NASA supports the companies without taking on the design, which stays in their hands. Ruggles speaks of more than 80 full-time equivalents per company, about 160 engineers in total, while the companies may use facilities at NASA centres. Going forward, SpaceX will make more Starship test flights, as well as long-duration and propellant-transfer demonstrations in orbit that are not needed for Artemis III but are critical for landings. Blue Origin will send its robotic Mark 1 to the Moon’s south pole. After Artemis III each company will attempt an uncrewed landing. Ruggles regards the landing itself as one of the biggest risks, because of the effect of exhaust on the ground, rocks and craters.