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 but historic: 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, including the first woman and the first person of color on the Moon, 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, a long way down from the old Apollo ladder. Where a Moon walk once meant a short hop out of a cramped two-person cabin, HLS gives astronauts far more room inside and stays that last 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

The way the contract is written matters to anyone watching the money. These firm-fixed-price, milestone-based awards pay out only as work is delivered, which shifts the risk of cost overruns onto the contractor rather than the taxpayer. The deal also turns the Moon into 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 drives down the price of a kilogram delivered to the Moon, and a depot-and-tanker model that works once works for every mission after it.

Current Status of Starship HLS

As of mid-2026, the program is running behind. The orbital propellant transfer demonstration, the make-or-break step, is aimed at 2026 and is not yet done. An uncrewed Starship HLS Moon landing demonstration is aimed at June 2027, and it requires the lander to send data from the surface for at least two hours. NASA is aiming for Artemis III, the first crewed Starship HLS Moon landing, around September 2028.

There has been real progress under the delays. 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 put it plainly: "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 even if the dates are not: prove orbital refueling, fly the uncrewed landing demo, then put boots on the Moon with a crew. Each step is meant to pay for and unlock the next, and HLS fits that pattern, because every refueling and reuse milestone here feeds the same overall plan aimed at Mars. The real bet is on the cost of it all. Bring the price of a Moon delivery down far enough, and a lasting presence on the Moon stops being a string of one-off missions and starts to look like routine transport.

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. The technology keeps advancing and the contracts pay out on delivery, but until propellant actually moves between ships in orbit, the Moon landing will keep sliding later.

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