Starship HLS

Starship HLS (Human Landing System) is the Moon version of SpaceX's Starship, the part of the rocket that actually sets down on the surface. NASA hired SpaceX to build it so Artemis astronauts can ride from lunar orbit down to the surface and back. It is the largest crewed Moon lander ever designed, roughly 50 meters (about 165 feet) tall, about the height of a 15-story building, and the Apollo Lunar Module that carried the last astronauts down in 1972 stood only about 7 meters.

What is Starship HLS?

NASA picked SpaceX's Starship to carry the next astronauts to the Moon on April 16, 2021, a $2.89 billion vote of confidence in a lander that did not yet exist. HLS is a stripped-down, Moon-only version of the same vehicle SpaceX is building to reach orbit and, one day, Mars. Its job is narrow: take Artemis crews the last leg, from lunar orbit down to the surface and back up.

Why Starship HLS Exists

NASA needed a privately built lander to put people back on the surface for the first time since Apollo 17, as a stepping stone toward a lasting presence there and eventually Mars. The choice was fought over. Competitors filed protests, the Government Accountability Office turned those protests down in July 2021, and the U.S. Court of Federal Claims upheld the selection on November 4 of that year.

NASA later added an Option B modification, worth $1.15 billion, announced November 15, 2022, for a second crewed landing on Artemis IV and a longer-term lander that carries four crew and more payload. That brings NASA's committed total to at least $4.04 billion.

How it Works

Six Raptor engines, three built for sea level and three for the vacuum of space, burn deeply chilled liquid methane and liquid oxygen using full-flow staged combustion, an efficient engine cycle that is famously hard to build. Fully fueled, the vehicle holds roughly 1,500 metric tons of propellant.

The hard part is getting that propellant all the way to the Moon. One launch cannot carry enough, so SpaceX has to first fill an orbiting Starship fuel depot using several tanker launches, then top off HLS before it heads for the Moon. Because the lander and the depot never come back down through Earth's atmosphere, they leave off the heat shield and the fins a normal Starship needs. Crew and cargo ride an elevator between the cabin and the surface, replacing the ladder Apollo crews climbed down. HLS gives astronauts far more room than Apollo's two-person cabin and supports surface stays of several days. The plan sends two astronauts down to the surface while two more wait aboard the Orion capsule in lunar orbit.

The Economics of Starship HLS

NASA's HLS awards are firm-fixed-price and milestone-based: they pay out only as work is delivered, which shifts the risk of cost overruns onto SpaceX rather than taxpayers. The deal also makes the Moon a testing ground for reusable, methane-fueled heavy lift and in-orbit refueling as commercial services, skills with a market far bigger than this one program. Each tanker flight that lands and flies again lowers the price of a kilogram delivered to the Moon, and a working depot-and-tanker system could serve later missions as well.

Current Status of Starship HLS

As of October 2026, the ship-to-ship propellant transfer test and the design certification review NASA requires are the next milestones. Starship did reach orbit for the first time on September 28, 2026, which the refueling flights need. NASA restructured Artemis on February 27, 2026: Artemis III, targeted for mid-2027, will test docking between Orion and one or both commercial landers in Earth orbit, and the first crewed landing moved to Artemis IV, targeted for early 2028, with lander readiness deciding whether SpaceX or Blue Origin carries that crew. Artemis II flew four astronauts around the Moon from April 1 to 10, 2026.

Refueling work is already under way. On March 14, 2024, Starship's third integrated flight test moved chilled propellant between tanks inside the ship, a key HLS milestone. NASA's Jeremy Kenny said: "Storing and transferring cryogenic propellant in orbit has never been attempted on this scale before, but this is a game-changing technology."

What Comes Next

The order of events is set: prove ship-to-ship refueling in orbit, fly an uncrewed landing demonstration that must send data from the lunar surface for at least two hours, then land a crew. Every refueling and reuse milestone also serves SpaceX's own plans for a city on the Moon and, later, Mars. NASA's 2021 plan targeted 2024 for the first crewed landing, and its current target is early 2028.

The Bottom Line

Starship HLS is a bet that the cheapest way back to the Moon is the biggest lander ever built, refueled in orbit by reusable rockets. Moving propellant between two ships in orbit is the next big step, and it is the step that sends the lander to the Moon.