[43][44] Before 2014, only two full-flow staged-combustion rocket engine designs had advanced enough to undergo testing: the Soviet RD-270 project in the 1960s and the Aerojet Rocketdyne Integrated Powerhead Demonstrator in the mid-2000s.

[76] The original design only featured a single downcomer, which terminated in a distribution manifold, directing propellant to the three sea level engines and the individual RVacs.

[80] The outer wall of the aft dome is covered in an insulation material, presumably to prevent frost from building up inside the engine bay during propellant load.

[81][78] Until Starship flight test 3, this section held the hydraulic power unit, which provided the three sea level engines with thrust vector control capability.

[85][86] Before 2014, only two full-flow staged-combustion rocket engine designs had advanced enough to undergo testing: the Soviet RD-270 project in the 1960s and the Aerojet Rocketdyne Integrated Powerhead Demonstrator in the mid-2000s.

[102] The engine structure itself is mostly aluminum, copper, and steel; oxidizer-side turbopumps and manifolds subject to corrosive oxygen-rich flames are made of an Inconel-like SX500 superalloy.

After the boostback burn, the booster's engines shut off with Super Heavy on a trajectory for a controlled descent to the launch site using its grid fins for minor course corrections.

[130] NASA has estimated that 16 launches in short succession (due to cryogenic propellant boil-off) would be needed to refuel Starship for one lunar landing partially.

[144][133][146] Musk cited numerous reasons for the change of material; low cost and ease of manufacture, increased strength of stainless steel at cryogenic temperatures, as well as its ability to withstand high heat.

[159] This was noted for its corrosion resistance and lower cost compared to carbon fiber but faced some challenges, particularly with interlaminar toughness at cryogenic temperatures.

[163] On 3 September 2020, the similar-looking Starship SN6 repeated the hop;[164] later that month, a Raptor vacuum engine underwent its first full duration firing at McGregor, Texas.

[168] Because SpaceX had violated its launch license and ignored warnings of worsening shock wave damage, the Federal Aviation Administration investigated the incident for two months.

[169][170][171] FAA space division chief Wayne Monteith said SpaceX's violation was “inconsistent with a strong safety culture”, and criticized the company for proceeding with the launch "based on 'impressions' and 'assumptions,' rather than procedural checks and positive affirmations".

[181]: 2 In June 2022, the Federal Aviation Administration determined that SpaceX must address more than 75 issues identified in the preliminary environmental assessment before integrated flight tests could start.

[182] In July 2022, Booster 7 tested the liquid oxygen turbopumps on all 33 Raptor engines, resulting in an explosion at the vehicle's base, which destroyed a pressure pipe and caused minor damage to the launchpad.

[121] Following separation, the Super Heavy booster completed its flip maneuver and initiated the boostback burn, but then experienced multiple successive engine failures and exploded.

[121][203][204] Blockage in a liquid oxygen filter caused one of the engines to fail in a way that resulted in the destruction of the booster, which occurred three and a half minutes into the flight at an altitude of ~90 km over the Gulf of Mexico.

[219] The goals for the test flight were for the Super Heavy booster to land on a 'virtual tower' in the ocean, and for the Ship to survive peak heating during atmospheric reentry.

[245] The same year, SpaceX was awarded a $102 million five-year contract to develop the Rocket Cargo program for the United States Space Force.

[267] Starship's low launch cost could also allow probes to use heavier, more common, cheaper materials, such as glass instead of beryllium for large telescope mirrors.

[267] Lee Feinberg, NASA HWO lead architect[267] and JWST manager,[268] stays in communication with SpaceX to track Starship's progress and has visited them in 2024 for that same purpose.

[267] The NASA Habitable Worlds Observatory will have a 6–8 meter mirror for now, but its design should be flexible to leverage launchers with potentially double the mass and volume by the time it launches in the 2040s.

[267] Handmer argues that Starship enables telescopes to scale up to the point of surface-level exoplanet imaging, perhaps big enough to detect seasonal migration patterns.

[267] In January 2022, SpaceX was awarded a $102 million five-year contract to develop the Rocket Cargo program for the United States Space Force.

[250] The five-year contract is intended to "determine exactly what a rocket can achieve when used for cargo transport",[269] and will see the Air Force Research Laboratory collect data during commercial launches of Starship.

The Department of Defense has planned a test with Starship as part of its program to demonstrate the ability to rapidly deploy up to 100 tons of cargo and supplies, a capability it calls point-to-point delivery (P2PD).

[281] To date, there has been one proof of concept experiment (MOXIE) demonstrating the extraction of oxygen from Martian carbon dioxide, with George Dvorsky writing for Gizmodo commenting that we are not "remotely close" to turning this "into something practical".

[118] Smaller facilities are present at the launch site: tanks surrounding the area containing methane, oxygen, nitrogen, helium, hydraulic fluid, etc.

[305] In 2021, the China Academy of Launch Vehicle Technology (CALT) showed a rendered video of a rocket noted to be "strikingly" similar to Starship in appearance and function.

[171] In 2023, prior to Starship's second test flight, SpaceX's vice president and ex-NASA engineer Bill Gerstenmaier made statements at the U.S. Senate on the importance of innovation in light of "strategic competition from state actors like China".