The maiden voyage of SLS is set for August 29, kicking off NASA’s return to the Moon and setting the stage for crewed missions.
NASA’s most powerful rocket is nearly ready to send an uncrewed Orion capsule on a 42-day journey to the Moon and back, but this deceptively straightforward plan involves a ton of moving parts—including a harrowing 5,000-degree reentry through Earth’s atmosphere. Here’s what you can expect from this historic mission, called Artemis 1, as NASA officially ushers in the Artemis era.
NASA’s Space Launch System (SLS) departed the Vehicle Assembly Building at Kennedy Space Center in Florida on August 16 and traveled to launchpad 39B. The rocket got the final “go for launch” August 22 after a flight readiness review. Should all go according to plan, SLS, with an uncrewed Orion capsule placed atop, will launch on Monday, August 29, during a two-hour window that starts at 8:33 a.m. ET. Backup windows are also in place for September 2 and September 5. You can watch a live stream of the Artemis 1 launch here.
The inaugural launch will send the $20.4 billion Orion on a 42-day journey to the Moon and back, in a mission that will require the capsule to travel a total distance of 1.3 million miles (2.1 million kilometers). Orion will enter into a lunar orbit and hang out for a few weeks before returning home. Splashdown in the Pacific Ocean is expected on October 10—assuming Orion survives reentry. Its heat shield will have to endure temperatures reaching 5,000 degrees Fahrenheit (2,760 degrees Celsius), as Orion is expected to hit the atmosphere at speeds reaching 25,000 miles per hour (40,000 kilometers per hour).
Artemis 1 is a test mission. It’ll be the first integrated trial of SLS and Orion, the latter of which was sent to space on a trial mission in 2014. As for SLS, this will be its first launch.
“This is a mission that truly will do what hasn’t been done and learn what isn’t known,” Mike Sarafin, Artemis 1 mission manager at NASA, said in a statement. “It will blaze a trail that people will follow on the next Orion flight, pushing the edges of the envelope to prepare for that mission.”
Sarafin is referring to Artemis 2, in which a crewed Orion capsule will attempt the same mission. Both Artemis 1 and 2 are precursor missions for the real deal, Artemis 3, in which NASA will attempt to land a man and woman on the lunar surface. Artemis 2 is currently scheduled for late 2024, while Artemis 3 could happen in the following year. The Artemis program as a whole is NASA’s effort to return humans to the lunar environment, but unlike Apollo, these missions are designed to keep us there. To that end, NASA and its international partners are planning to build a lunar space station, called Gateway, to support activities both on and around the Moon.
Related: What to know about Lunar Gateway, NASA’s future Moon-orbiting space station.
Artemis seeks a sustainable and permanent return to the Moon, but in reality it’s about something far grander. “Our sights are not set on the Moon,” Reid Wiseman, chief astronaut at NASA Johnson, told reporters at a briefing on August 5. “Our sights are clearly set on Mars.” Indeed, the technologies and experiences gained during Artemis will prepare NASA and its partners for crewed treks to the Red Planet, which could happen in the late 2030s or early 2040s. For all this to happen, however, NASA needs Artemis 1 to succeed.
A core technology for the Artemis program is the $23.8 billion Space Launch System, which NASA administrator Bill Nelson described as the “only rocket that can take humans to the Moon.” Blasting off with 8.8 million pounds of thrust, it’s the most powerful rocket ever built. The super heavy-lift launch vehicle will be more powerful than the Apollo-era Saturn V (7.5 million pounds of thrust), the system that launched the Space Shuttle (7.8 million pounds of thrust), and SpaceX’s Falcon Heavy (5 million pounds of thrust). SpaceX’s upcoming Starship, however, will blow it out of the water with 17 million pounds of thrust at first launch. For Artemis 1, SLS’s job will be to deliver Orion to Earth orbit, from where the capsule can commence on its journey to the Moon.
At launch, the 322-foot-tall (98-meter) rocket will weigh nearly 6 million pounds. For Artemis 1, NASA will use the Block 1 variant of SLS, which features the core stage (equipped with four hydrogen-fueled RS-25D engines), a pair of five-segment solid rocket boosters attached to the side, and the Orion capsule on top.
