Artemis I Heads to Launch Pad For Wet Dress Rehearsal Test

NASA’s Space Launch System rocket and Orion spacecraft rolled out of the Vehicle Assembly Building at Kennedy Space Center this evening on the way to its launch pad for the first time. About two weeks from now, the agency will conduct a Wet Dress Rehearsal — a practice countdown while the rocket is fueled. If all goes well, the first launch, Artemis I, could take place in June.

The SLS/Orion combination for Artemis I was assembled inside the VAB surrounded by scaffolding. This was the first time it could be seen in its entirety as it began the 4-mile trip to Launch Complex-39B attached to its mobile launch gantry atop Crawler-Transporter 2.

The orange Boeing-built SLS core stage has Northrop Grumman five-segment Solid Rocket Boosters on each side. Above the core stage is the Boeing-built Interim Cryogenic Propulsion Stage, then the Orion crew spacecraft and Launch Abort System, all in white.

The top speed of the Crawler-Transporter is 0.82 miles per hour. The trip, which started about 6:00 pm ET, is expected to take about 11 hours until it is “hard down” at the launch pad. If all goes according to plan, the Wet Dress Rehearsal test will take place around April 3.

The 322-foot tall combination, or stack, is reminiscent of the Space Shuttle without the airplane-like orbiter. Indeed, the core stage is based on the shuttle’s External Tank. It is powered by the same Aerojet Rocketdyne RS-25 engines, which were designed to be reusable. NASA has 16 left over, all of which have flown in space already. Four are needed for each SLS. The shuttle needed three and they were attached to the orbiter, not the External Tank.

The shuttle also had two SRBs. Those had four segments while these have five.

The shuttle’s orbiter housed the crew and cargo. For Artemis, the crew will be the Orion spacecraft, somewhat similar to an Apollo capsule, which has a Service Module provided by the European Space Agency. This version of SLS is not designed to launch cargo.

NASA will not set a date for the launch of Artemis I, an uncrewed test flight out beyond the Moon and back, until after the Wet Dress Rehearsal is done and the data analyzed, but no earlier than June.

Artemis I has been delayed again and again. In 2014, NASA committed  to the first launch in November 2018. That slipped to December 2019-June 2020, then to mid-late 2021, and then 2022.

The Government Accountability Office (GAO) and NASA’s Office of Inspector General (OIG) have published many reports documenting the cost growth and schedule delays for SLS, but that has not dampened congressional support for the program. Congress directed NASA to build SLS and Orion in the 2010 NASA Authorization Act. The goal is to send humans back to the Moon for the first time since the Apollo program and someday to Mars.

If Artemis I is successful, it will be two more years before the next launch, Artemis II, the first to carry a crew around the Moon. The third SLS/Orion flight, Artemis III, will deliver astronauts to lunar orbit where they will dock with a Human Landing System to take them down to and back from the surface. Then they will redock with Orion and return to Earth. NASA’s current plan is for that mission to take place in 2025.

At a March 1 House Science, Space, and Technology Committee hearing, NASA Inspector General Paul Martin testified that by FY2025, NASA will have spent $93 billion on the Artemis program starting in FY2011. Of that, $53 billion is for FY2021-2025. He does not think Artemis I will launch until 2026 at the earliest. His office estimates the cost for each of the first four Artemis missions at $4.1 billion.