Starship development history
The SpaceX Starship is a fully-reusable launch vehicle and spacecraft that is being privately developed by SpaceX. It is designed to be a long-duration cargo and, eventually, passenger-carrying spacecraft. The development of the Starship began around 2012.
While the Starship program had only a small development team during the early years, and a larger development and build team since late 2018, Musk made Starship the top SpaceX development priority following the first human spaceflight launch of Crew Dragon in May 2020, except for anything related to reduction of crew return risk.
The launch vehicle was initially mentioned in public discussions by SpaceX CEO Elon Musk in 2012 as part of a description of the company's overall Mars system architecture, then known as Mars Colonial Transporter (MCT). It was proposed as a privately-funded development project to design and build a spaceflight system of reusable rocket engines, launch vehicles and space capsules to eventually transport humans to Mars and return them to Earth.
As early as 2007 however, Musk had stated a personal goal of eventually enabling human exploration and settlement of Mars. Bits of additional information about the mission architecture were released in 2011–2015, including a 2014 statement that initial colonists would arrive at Mars no earlier than the middle of the 2020s, and SpaceX began development of the large Raptor rocket engine for the MCT before 2014.
Musk stated in a 2011 interview that he hoped to send humans to Mars' surface within 10–20 years, and in late 2012 that he envisioned the first colonists arriving no earlier than the middle of the 2020s.
In October 2012, Musk first publicly articulated a high-level plan to build a second reusable rocket system with capabilities substantially beyond the SpaceX launch vehicles on which SpaceX had by then spent several billion US dollars. This new vehicle was to be "an evolution of SpaceX's Falcon 9 booster ... much bigger [than Falcon 9]." But Musk indicated that SpaceX would not be speaking publicly about it until 2013. In June 2013, Musk stated that he intended to hold off any potential IPO of SpaceX shares on the stock market until after the "Mars Colonial Transporter is flying regularly."
In February 2014, the principal payload for the MCT was announced to be a large interplanetary spacecraft, capable of carrying up to 100 tonnes (220,000 lb) of passengers and cargo. Musk stated that MCT will be "100 times the size of an SUV". According to SpaceX engine development head Tom Mueller, concept designs at the time indicated SpaceX could use nine Raptor engines on a single rocket, similar to the use of nine Merlin engines on each Falcon 9 booster core, in order "to put over 100 tons of cargo on Mars." At that time, it appeared that the large rocket core that would be used for the booster to be used with MCT would be at least 10 meters (33 ft) in diameter—nearly three times the diameter and over seven times the cross-sectional area of the Falcon 9 booster cores—and was expected to have up to three rocket cores with a total of at least 27 engines.
By August 2014, media sources speculated that the initial flight test of the Raptor-driven super-heavy launch vehicle could occur as early as 2020, in order to fully test the engines under orbital spaceflight conditions; however, any colonization effort was then reported to continue to be "deep into the future".
Interplanetary Transport System
In January 2015, Musk said that he hoped to release details of the "completely new architecture" for the Mars transport system in late 2015 but those plans changed and, by the end of the year, the plan to publicly release additional specifics had moved to 2016. Musk stated in June 2016 that the first uncrewed MCT Mars flight could happen as early as 2022, to be followed by the first crewed MCT Mars flight departing as early as 2024. By mid-2016 the company continued to call for the arrival of the first humans on Mars no earlier than 2025. By 2016, the rocket had not yet been given a formal name by SpaceX, although Musk commented on a proposal on Twitter to name it "Millennium". In his September 2016 announcement, Musk referred to the vehicle versions as the "ITS booster", the "Interplanetary Spaceship", and the "ITS tanker".
In mid-September 2016, Musk noted that the Mars Colonial Transporter name would not continue, as the system would be able to "go well beyond Mars", and that a new name would be needed. The name selected was Interplanetary Transport System (ITS), although in an AMA on Reddit on Oct 23, 2016, Musk stated, "I think we need a new name. ITS just isn't working. I'm using BFR and BFS for the rocket and spaceship, which is fine internally, but...", without stating what the new name might be.
Musk unveiled details of the space mission architecture, launch vehicle, spacecraft, and Raptor engines that power the vehicles at the 67th International Astronautical Congress on September 27, 2016. The first firing of a Raptor engine occurred on a test stand in September 2016 as well.
In October 2016, Musk indicated that the initial prepreg carbon-fiber tank test article, built with no sealing liner, had performed well in initial cryogenic fluid testing, and that a pressure test of the tank at approximately 2/3 of the design burst pressure was slated for later in 2016, with the very large tank placed on an ocean barge for the test. This test was successfully completed in November 2016.
In July 2017, Musk indicated that the architecture had "evolved quite a bit" since the 2016 articulation of the Mars architecture. A key driver of the updated architecture was to be making the system useful for substantial Earth-orbit and cislunar launches so that the system might pay for itself, in part, through economic spaceflight activities in the near-Earth space zone. In September 2018, a less drastic redesign was announced, stretching the second stage slightly and adding radially-steerable forward canards and aft fins, used for pitch control in a new reentry profile resembling a descending skydiver. The aft fins act as landing legs, with a third leg on the top that looks identical but serves no aerodynamic purpose.
The ITS stack was composed of two stages. The first stage was always to be an "ITS booster" while the second stage would have been either an "Interplanetary Spaceship" (for beyond-Earth-orbit missions) or an "ITS tanker" (for on-orbit propellant transfer operations).
Both stages of the ITS were to be powered by Raptor bipropellant liquid rocket engines utilizing the full flow staged combustion cycle with liquid methane fuel and liquid oxygen oxidizer. Both propellants would be fully in the gas phase before entering the Raptor combustion chamber. Both stages were intended to utilize a bleed-off of the high-pressure gas for autogenous pressurization of the propellant tanks, eliminating the problematic high-pressure helium pressurization system used in the Falcon 9 launch vehicle. The self-pressurization gas system is a critical part of SpaceX strategy to reduce launch vehicle fluids from five in their legacy Falcon 9 vehicle family to just two, eliminating not only the helium tank pressurant but all hypergolic propellants as well as nitrogen for cold-gas reaction-control thrusters.
The overall launch vehicle height, first stage and the integrated second-stage/spacecraft, was 122 m (400 ft). Both stages of the ITS were to have been constructed of lightweight-yet-strong carbon fiber, even the deep-cryogenic propellant tanks, a major change from the aluminum-lithium alloy tank and structure material used in SpaceX Falcon 9 family of launch vehicles. Both stages are fully reusable and will land vertically, technology initially developed on the Falcon 9 launch vehicle first stages in 2012–2016. Gross liftoff mass is 10,500 tonnes (23,100,000 lb) at a lift-off thrust of 128 meganewtons (29,000,000 lbf). ITS would be able to carry a payload to low-Earth orbit of 550 tonnes (1,210,000 lb) in expendable-mode and 300 tonnes (660,000 lb) in reusable mode.
The ITS booster was a 12 m-diameter (39 ft), 77.5 m-high (254 ft), reusable first stage, to be powered by 42 sea-level rated Raptor engines producing some 3,024 kilonewtons (680,000 lbf) of thrust in each engine. Total booster thrust would have been approximately 130 MN (29,000,000 lbf), several times the 36 MN (8,000,000 lbf) thrust of the Saturn V Moon mission launch vehicle.
The design engine configuration included 21 engines in an outer ring and 14 in an inner ring, with these 35 engines fixed in place. The center cluster of seven engines were to be gimbaled for directional control, although some directional control to the rocket was to be performed by utilizing differential thrust on the fixed engines. Design thrust on each engine was aiming to be variable between 20 and 100 percent of rated thrust.
Methane/oxygen would also be used to power the control thrusters, as gas thrusters rather than the subcooled liquid used to power the main engines. The methalox control thrusters were to be used to control booster orientation in space, as well as to help provide additional accuracy in landing once the velocity of the descending booster has slowed.
The design was intended to use about 7% of the total propellant load at launch in order to support the reusable aspect and bring the booster back to the launch pad for a vertical landing, assessment, and relaunch, assuming a separation velocity of approximately 8,650 km/h (5,370 mph). The design called for grid fins to be used during atmospheric reentry, once the atmosphere is sufficiently dense, to control the attitude of the rocket and fine tune the landing location. The booster return flights were expected to encounter loads lower than those experienced on the Falcon 9 reentries, principally because the ITS would have both a lower mass ratio and a lower density than Falcon 9. The booster was to be designed for 20 g nominal loads, and possibly as high as 30–40 gs without breaking up.
In contrast to the landing approach used on SpaceX's mid-2010s reusable rocket first stages—either a large, flat concrete pad or downrange floating landing platform used with Falcon 9 and Falcon Heavy—the ITS booster was to be designed to land on the launch mount itself, where it may then be refilled with propellant and checked out for follow-on flights.
Spacecraft that operate briefly as upper stages during launch
The ITS did not have a dedicated and single-function second stage in the way most launch vehicles have had. Instead, the upper stage function of gaining sufficient velocity to place a payload into Earth orbit is provided as a relatively short term role by a spacecraft that has all the requisite systems for long-duration spaceflight. This is not a role that most upper stages have had in launch vehicle designs through the 2010s, as typical upper stage on-orbit life is measured in hours. Previous exceptions to this norm exist, for example the Space Shuttle orbiter provided part of the boost energy and all of the second stage energy for lofting itself into low-Earth orbit. Differences also exist: the Space Shuttle expended its propellant tank and primary launch vehicle structure on ascent, whereas the ITS first- and second-stage options are designed to be fully reusable.
In the 2016 design, SpaceX had identified two spacecraft that would also play the upper stage role on each Earth-away launch: the "Interplanetary Spaceship" and the "ITS tanker". Both spacecraft are the same physical external dimensions: 49.5 m (162 ft)-long and 12 m (39 ft)-diameter 17 m (56 ft) across at the widest point. Both designs were powered by six vacuum-optimized Raptor engines, each producing 3.5 MN (790,000 lbf) thrust, and were to have had three lower-expansion-ratio Raptor engines for in-space maneuvering as well as during descent and landing to allow for reuse on future launches.
The Interplanetary Spaceship was a large passenger-carrying spacecraft design proposed by SpaceX as part of their ITS launch vehicle in September 2016. The ship would operate as a second-stage of the orbital launch vehicle on Earth-ascents—and would also be the interplanetary transport vehicle for both cargo and passengers—capable of transporting up to 450 tonnes (990,000 lb) of cargo per trip to Mars following propellant-refill in Earth orbit.
In addition to use during maneuvering, descent and landing, the three lower-expansion-ratio Raptor engines were also to have been used for initial ascent from the surface of Mars. In 2016, the first test launch of a spaceship was not expected until 2020 or later, and the first flight of the ITS booster was expected to follow a year or more later.
Early Mars flights—in the mid-2020s or later—were expected to carry mostly equipment and few people.
The ITS tanker is a propellant tanker variant of the ITS second stage. This spacecraft design was to be used exclusively for launch and short-term holding of propellants to be transported to low-Earth orbit. Once on orbit, a rendezvous operation was to have been effected with one of the Interplanetary Spaceships, plumbing connections made, while a maximum of 380 tonnes (840,000 lb) of liquid methane and liquid oxygen propellants would be transferred in one load to the spaceship. To fully fuel an Interplanetary Spaceship for a long-duration interplanetary flight, it was expected that up to five tankers would be required to launch from Earth, carrying and transferring a total of nearly 1,900 tonnes (4,200,000 lb) of propellant to fully load the spaceship for the journey.
Both stages were to be designed by SpaceX to be fully reusable and were to land vertically, using a set of technologies previously developed by SpaceX and tested in 2013–2016 on a variety of Falcon 9 test vehicles as well as actual Falcon 9 launch vehicles.
Importantly, the "fully and rapidly reusable" aspect of the ITS design was the largest factor in the SpaceX analysis for bringing down the currently huge cost of transporting mass to space, in general, and to interplanetary destinations, in particular. While the transport system under development in 2016-2017 relied on a combination of several elements to make long-duration beyond Earth orbit (BEO) spaceflights possible by reducing the cost per ton delivered to Mars, the reusability aspect of the launch and spacecraft vehicles alone was expected by SpaceX to reduce that cost by approximately 2 1/2 orders of magnitude over what NASA had previously achieved on similar missions. Musk stated that this is over half of the total 4 1/2 orders of magnitude reduction that he believes is needed to enable a sustainable settlement off Earth to emerge.
The concept of operations for ITS launches envisioned the fully loaded second-stage reaching orbit with only minimal propellant remaining in the Interplanetary Spaceship's tanks. Then, while the spaceship remained in Earth orbit, three to five ITS tankers would be launched from Earth carrying additional methane fuel and liquid oxygen oxidizer to rendezvous with, and transfer propellant to, the outgoing spaceship. Once refueled, the spaceship was to perform a trans-Mars injection burn, departing Earth orbit for the interplanetary portion of the journey.
Big Falcon Rocket
In September 2017, at the 68th annual meeting of the International Astronautical Congress, SpaceX unveiled the updated vehicle design. Musk said, "we are searching for the right name, but the code name, at least, is BFR."
The Big Falcon Rocket (BFR), also informally known as Big Fucking Rocket, was a 9-meter (30 ft) diameter carbon-composite launch vehicle, using methalox-fueled Raptor rocket engine technology directed initially at the Earth-orbit and cislunar environment, later, for flights to Mars.
The BFR was cylindrical and included a small delta wing at the rear end which included a split flap for pitch and roll control. The delta wing and split flaps were said to be needed to expand the flight envelope to allow the ship to land in a variety of atmospheric densities (none, thin, or heavy atmosphere) with a wide range of payloads (small, heavy, or none) in the nose of the ship.:18:05–19:25 Three versions of the ship were described: BFS cargo, BFS tanker, and BFS crew. The cargo version would be used to launch satellites to low Earth orbit—delivering "significantly more satellites at a time than anything that has been done before"—as well as for cargo transport to the Moon and Mars. After retanking in a high-elliptic Earth orbit the spaceship was being designed to be able to land on the Moon and return to Earth without further refueling.:31:50
The engine layout, reentry aerodynamic surface designs, and even the basic material of construction have each changed markedly since the initial public unveiling of the BFR in 2017, in order to balance objectives such as payload mass, landing capabilities, and reliability. The initial design at the unveiling showed the ship with six Raptor engines (two sea-level, four vacuum), aerodynamic control surfaces of a delta wing with split flaps, and a plan to build both stages of the launch vehicle out of carbon composite materials.
By late 2017, SpaceX added a third sea-level engine to the conceptual design to increase engine-out capability and allow landings with greater payload mass, bringing the total number of engines to seven.
Additionally, the BFR was shown to theoretically have the capability to carry passengers and/or cargo in rapid Earth-to-Earth transport, delivering its payload anywhere on Earth within 90 minutes.
By September 2017, Raptor engines had been tested for a combined total of 1,200 seconds of test firing time over 42 main engine tests. The longest test was 100 seconds, which was limited by the size of the propellant tanks at the SpaceX ground test facility. The test engine operates at 20 MPa (200 bar; 2,900 psi) pressure. The flight engine is aimed for 25 MPa (250 bar; 3,600 psi), and SpaceX expects to achieve 30 MPa (300 bar; 4,400 psi) in later iterations. In November 2017, SpaceX president and COO Gwynne Shotwell indicated that approximately half of all development work on BFR was then focused on the Raptor engine.
The aspirational goal in 2017 was to send the first two cargo missions to Mars in 2022, with the goal to "confirm water resources and identify hazards" while deploying "power, mining, and life support infrastructure" in place for future flights, followed by four ships in 2024, two crewed BFR spaceships plus two cargo-only ships bringing additional equipment and supplies with the goal of setting up the propellant production plant.
By early 2018, the first ship using carbon composite structure was under construction, and SpaceX had begun building a new permanent production facility to build the 9-meter vehicles at the Port of Los Angeles. Manufacture of the first ship was underway by March 2018 in a temporary facility at the port, with first suborbital test flights planned for no earlier than 2019. The company continued to state publicly its aspirational goal for initial Mars-bound cargo flights of BFR launching as early as 2022, followed by the first crewed flight to Mars one synodic period later, in 2024, consistent with the no-earlier-than dates mentioned in late-2017.
Back in 2015, SpaceX had been scouting for manufacturing facility locations to build the large rocket, with locations being investigated in California, Texas, Louisiana, and Florida. By September 2017, SpaceX had already started building launch vehicle components: "The tooling for the main tanks has been ordered, the facility is being built, we will start construction of the first ship [in the second quarter of 2018.]"
In March 2018, SpaceX announced that it would manufacture its next-generation, 9-meter-diameter (30 ft) launch vehicle and spaceship at a new facility the company is constructing in 2018–2019 on Seaside Drive at the Port of Los Angeles. The company had leased an 18-acre (7.3 ha) site for 10 years, with multiple renewals possible, and will use the site for manufacturing, recovery from shipborne landings, and refurbishment of both the booster and the spaceship. Final regulatory approval of the new manufacturing facility came from the Board of Harbor Commissioners in April 2018, and the Los Angeles City Council in May. By that time, approximately 40 SpaceX employees were working on the design and construction of BFR. Over time, the project was expected to have 700 technical jobs. The permanent Port of Los Angeles facility was projected to be a 203,500-square-foot (18,910 m2) building that would be 105 feet (32 m) tall. The fully assembled launch vehicle was expected at that time to be transported by barge, through the Panama Canal, to Cape Canaveral in Florida for launch.
In August 2018, for the first time, the US military publicly discussed interest in using the BFR. The head of USAF Air Mobility Command was specifically interested in BFRs ability to move up to 150 t (330,000 lb) of cargo to anywhere in the world using the projected Earth-to-Earth capability in under 30 minutes, for "less than the cost of a C-5". They projected the large transport capability "could happen within the next five to 10 years."
Starship and Super Heavy
In a September 2018 announcement of a planned 2023 lunar circumnavigation mission, a private flight called #dearMoon project, Musk showed a redesigned concept for the BFR second stage and spaceship with three rear fins and two front canard fins added for atmospheric entry, replacing the previous delta wing and split flaps shown a year earlier. The revised BFR design was to use seven identically-sized Raptor engines in the second stage; the same engine model as would be used on the first stage. The second stage design had two small actuating canard fins near the nose of the ship, and three large fins at the base, two of which would actuate, with all three serving as landing legs. Additionally, SpaceX also stated later that September that they were "no longer planning to upgrade Falcon 9 second stage for reusability." The two major parts of the re-designed BFR were given descriptive names in November: "Starship" for the upper stage and "Super Heavy" for the booster stage, which Musk pointed out was "needed to escape Earth's deep gravity well (not needed for other planets or moons)."
In May 2019, the final Starship design changed back to six Raptor engines, with three optimized for sea-level and three optimized for vacuum. Also clarified was that the initial prototype Super Heavy will be full size, but was subsequently clarified that it would make initial test flights with less than the full complement of engines, perhaps approximately 20.
As the Raptor engine design was iterated, and higher thrust versions tested well on the test stand, the number of engines in the Super Heavy booster stage changed. Super Heavy was initially announced to have as many as 37 Raptor engines on the first stage, and a design with 31 engines was the public plan as late as May 2020. However, in August 2020, Musk stated that the design had changed: "It might be 28 engines," as a result of engine design changes including increased chamber pressure and a higher thrust-to-weight ratio.
In August 2020, Elon Musk expected a Super Heavy prototype for September or October.
Prototypes and testing
|Name||Start of construction||Decommissioned||Construction site||Status||Flights||Notes|
|Starhopper||December 2018||August 2019||Boca Chica, Texas||Retired||3|
|Mk1||December 2018||November 2019||Boca Chica, Texas||Destroyed||0||On 20 November 2019, the Mk1 test article came apart in a tank pressure test.|
|Mk2||c. December 2018 – c. May 2019||November 2019||Cocoa, Florida||Scrapped||0||Was never completed, described as dead before arrival on November 2019.|
|Mk4||October 2019||November 2019||Cocoa, Florida||Suspended||0||Unknown stage of completion, presumed not assembled at all (only some components made); perhaps to be scrapped. Described[when?] as dead before arrival.|
|SN1[a]||c. October 2019||February 2020||Boca Chica, Texas||Destroyed||0||Originally called Mk3, renamed to SN1 in December 2019. Destroyed during a pressure test on 28 February 2020.|
|SN2||February 2020||March 2020||Boca Chica, Texas||Retired||N/A||Designated SN2 but was simply a small scale test tank used to test welding quality on the thrust puck found on the bottom of the vehicle where three sea-level Raptor engines would be mounted. The 8 March 2020 test was motivated by the failure of the SN1 thrust puck during a cryogenic tank pressure test.|
|SN3||March 2020||April 2020||Boca Chica, Texas||Destroyed||0||On 3 April 2020, it was destroyed during tank testing due to a test configuration error. Had been slated for a Raptor static fire and short-duration low-altitude test flights.|
|SN4||March 2020||May 2020||Boca Chica, Texas||Destroyed||0||Completed five Raptor static fire tests and planned for short duration low altitude test flights with one mounted Raptor engine. First full Starship tank to pass cryogenic pressure test and Raptor static fire. It was destroyed on 29 May 2020 after a static fire test of its single Raptor engine due to a failure with the Ground Support Equipment's quick disconnect function. SN4 was planned to make a short hop test flight once regulator suborbital launch license would have been received.|
|SN5||April 2020||N/A||Boca Chica, Texas||Undergoing checkout/repairs||1||Single Raptor SN27 engine. Successful static fire test on 30 July 2020 and 150-meter hop on 4 August 2020. Elon Musk hopeful for further test hops.|
|SN6||May 2020||N/A||Boca Chica, Texas||Undergoing checkout/repairs||1||Single Raptor SN29 engine. Successful static fire test on 23 August 2020 and 150-meter hop on 3 September 2020.|
|SN7||May 2020||June 2020||Boca Chica, Texas||Destroyed||N/A||Designated SN7 but was only a small scale test tank. During a test on 15 June 2020, the tank began to leak at a pressure of 7.6 bar. After repairs, the tank was tested to destruction on 23 June 2020.|
|SN7.1||July 2020||September 2020||Boca Chica, Texas||Destroyed||N/A||New alloy test tank taken to burst pressure (8 bar) on 23 September 2020.|
|SN8||July 2020||N/A||Boca Chica, Texas||Undergoing testing||0||Currently on the test stand with aerodynamic control fins, three Raptor engines, and a nose cone installed. Successful static fire test on 20 October 2020. A high-altitude flight to 15 km is planned.|
|SN9||August 2020||N/A||Boca Chica, Texas||Under construction||0||Currently being stacked in midbay.|
|SN10||September 2020||N/A||Boca Chica, Texas||Under construction||0||Currently being stacked in midbay.|
|SN11||September 2020||N/A||Boca Chica, Texas||Under construction||0|
|SH SN1||September 2020||N/A||Boca Chica, Texas||Under construction||0||First Super Heavy booster prototype. Could hop with as few as two Raptor engines.|
|SN12||September 2020||N/A||Boca Chica, Texas||Under construction||0|
|SN14||October 2020||N/A||Boca Chica, Texas||Under construction||0|
On 8 December 2018, nine months after starting construction of some parts of the first test article carbon composite Starship low-altitude test vehicle, Musk announced a "counter-intuitive new design approach" would be taken by the company: the primary construction material for the rocket's structure and propellant tanks would be "fairly heavy...but extremely strong" metal, subsequently revealed to be stainless steel. Musk revealed on 23 December 2018 that the initial test article—the Starship Hopper, Hopper, or Starhopper— had been under construction there for several weeks, out in the open on SpaceX property. The Starhopper was being built from a 300-series stainless steel. According to Musk, the reason for using this material is that "it's [stainless steel] obviously cheap, it’s obviously fast—but it's not obviously the lightest. But it is actually the lightest. If you look at the properties of a high-quality stainless steel, the thing that isn’t obvious is that at cryogenic temperatures, the strength is boosted by 50 percent." The high melting point of 300-series still would mean the leeward side of Starship would need no insulation during reentry, while the much hotter windward side would be cooled by allowing fuel or water to bleed through micropores in a double-wall stainless steel skin, removing heat by evaporation. The Starhopper had a single engine and was used for a test flight to develop the landing and low-altitude/low-velocity control algorithms.
By late May 2019, while the Starhopper was preparing for untethered flight tests in South Texas, they were building two high-altitude prototypes simultaneously, Mk1 in Texas and Mk2 in Florida. The two ships were constructed by competing teams—that were required to share progress, insights, and build techniques with the other team, but neither team is required to use the other team's techniques. The larger Mk1 and Mk2 test vehicles featured three Raptor methalox engines meant to reach an altitude of no more than 5 km (3.1 mi), and the initial flight was expected no earlier than the first half of 2019. Construction of a Mk3 prototype began in late-2019. A first orbital flight was not expected until Mk4 or Mk5 in mid 2020. The build of the first Super Heavy booster stage was projected to be able to start by September. At the time, neither of the two orbital prototypes yet had aerodynamic control surfaces nor landing legs added to the under construction tank structures, and Musk indicated that the design for both would be changing once again. On 21 September 2019, the externally-visible "moving fins" began to be added to the Mk1 prototype, giving a view into the promised mid-2019 redesign of the aerodynamic control surfaces for the test vehicles.
In July 2019, the Starhopper made its initial flight test, a "hop" of approximately 20 m (66 ft) altitude, and a second and final "hop" in August, reaching an altitude of approximately 150 m (490 ft) and landing approximately 100 m (110 yd) from the launchpad, demonstrating the first use of the Raptor engine in real flight.
Mk1, Mk2, Mk3, Mk4
SpaceX completed the external structure of the Starship Mk1 in time for Musk's public update in September 2019. Watching the construction in progress before the event, observers circulated photos online and speculated about the most visible changes, including a move to two tail fins from the earlier three. During the event, Musk added that landing would now be accomplished on six dedicated landing legs, following a re-entry protected by ceramic heat tiles. Updated specifications were provided: when optimized, Starship was expected to mass at 120,000 kg (260,000 lb) empty and be able to initially transport a payload of 100,000 kg (220,000 lb) with an objective of growing that to 150,000 kg (330,000 lb) over time. Musk suggested that an orbital flight might be achieved by the fourth or fifth test prototype in 2020, using a Super Heavy booster in a two-stage-to-orbit launch vehicle configuration, and emphasis was placed on possible future lunar missions.
In September 2019, Elon Musk unveiled Starship Mk1, and in 20 November 2019, the Mk1 test article came apart in a tank pressure test in Texas. The same day, SpaceX stated they would stop developing Mk1 and Mk2 and move on to work on the Mk3 and Mk4 articles. Construction began on the Starship Mk4 in Florida by mid-October 2019. A few weeks later, the work on the vehicles in Florida paused, with apparent cancellation of Mk4. Some assemblies that had been built in Florida were transported to the Texas assembly location in Boca Chica; there was reportedly an 80% reduction in the workforce at the Florida assembly location as SpaceX paused activities there. SpaceX's Starship development work was now focused on the Texas site.
Data from: 
Starship SN1 (Mk3) and SN2
In December 2019, Musk announced that the Starship Mk3 would be redesignated "Starship SN1" and there would be at least minor design improvements at least through Starship SN20. Musk also explained that there was a change in the production of Starship. Some parts are now stamped and TIP TIG welded vs bump-formed and flux core welded. The new production process guarantees stronger joints and a mass reduction of 20%.
In January 2020, SpaceX performed pressurization tests on two test article tanks in Boca Chica. One such test took place on 10 January 2020, when a test tank was intentionally destroyed by over-pressurizing it; the tank achieved pressure of 7.1 bar (710 kPa). Later, another test tank underwent at least two pressurization tests; in the first experiment, on Monday 27 January 2020, the test tank withstood a pressure of 7.5 bar (750 kPa) before springing a leak. The leak was welded and the tank subjected to cryogenic pressure test on 28 January 2020, when the tank was intentionally pressurized until it ruptured and was destroyed at the pressure of 8.5 bar (850 kPa). The test was however considered a success despite the destruction of the tank, as the pressure reached, 8.5 bar (850 kPa), the pressure the tank needed to hold to be considered safe for human spaceflight; that is, the tank demonstrated a safety factor of 1.4 (1.4 times the operational pressure).[non-primary source needed][original research?]
Starship SN1 (originally known as Starship Mk3) was stated to be "designed for orbit" according to SpaceX. Later on, it was unclear whether this was the case (that SN1 would fly to orbit), and whether Starship SN1 would be used only for static fire testing (with one or more Raptor engines installed) and perhaps for one or more suborbital flights taking the vehicle to a 20 kilometer altitude with a soft landing back to Boca Chica.
SpaceX began stacking SN1 in February 2020 after a series of pressurization tests on propellant tank prototypes. The weld quality of the rings had been improved but SN1 failed a cryogenic pressurization test on 28 February 2020 due to a design failure in the lower tank thrust structure and the test article was destroyed. The structure ruptured from the bottom up, with most of the top part sent flying in the air and crashing into ground. At the time of the rupture, the SN1 vehicle had no nose cone, flight control structures, or Raptor engines installed, and was positioned on a test stand. The loss of SN1 was similar to the loss of Starship Mk1 in November 2019, leaving little of the vehicle intact. There were no injuries.
After the incident, SpaceX announced they were focusing their efforts on the next test article, Starship SN2. SpaceX adjusted their Starship SN2 testing plans to verify that the failure had been corrected, and conducted a successful test using much shorter SN2 tank structure on 8 March 2020.
Starship SN3 and SN4
In March 2020, Musk discussed SpaceX's future plans for Starship prototype tests. Starship SN3 was planned to be used for static fire tests and short hops, while SN4 will be used for longer flights.
Starship SN3 was destroyed during testing on 3 April 2020.. The cause of the failure was a testing configuration error. The liquid oxygen tanks housed in the lower part of the prototype were pressurised with nitrogen in order to keep them pressurised and structurally capable of withstanding the weight of the full methane tanks undergoing testing. A valve was inadvertently commanded to open resulting in pressure loss and structural failure as the lower portion of the prototype crumbled under the weight of the heavy methane tanks. While Starship SN3 was originally planned to be used for static fire tests and short hops, this setback delayed the testing timeline by a few weeks.[clarification needed] SN4 was built reusing parts[which?] of SN3 not damaged during the mishap.
Starship SN4 passed cryogenic pressure testing on 26 April 2020, making it the first prototype since the smaller SN2 test tank to do so. On 5 and 7 May 2020, SN4 passed two static fires: One using the main tanks, while the other used the fuel header tank. Three nights later after uninstalling the engine, a new cryogenic pressure test was conducted. The prototype achieved 7.5 bar of pressure. On 19 May 2020 during the third test firing of the engine, vibrations shook loose the methane fuel piping in the engine causing a leak which ignited and spread to flammable insulation, the fire caused significant damage to the base of the rocket and destroyed the control wiring leaving SpaceX unable to command the depressurization of the fuel tanks for two days. SN4 was destroyed on 29 May 2020 after a successful static fire test of its single Raptor engine, due to a failure with the Ground Support Equipment's quick disconnect function.
Starship SN5 and SN6
In March 2020, Musk had set "an aspirational goal" of using SN5 or SN6 to conduct an orbital flight of Starship before the end of 2020. After a successful static fire test on 30 July 2020, SN5 completed a 150-meter flight on 4 August 2020. SN5 may have a second test flight to follow. After the success of SN5, SN6 completed a static fire on 24 August 2020. On September 3rd Starship SN6 has performed a 150-meter hop. Given that only a single rocket engine has been installed on SN6, the current iteration of SN6 will not conduct an orbital flight.
SN7, SN7.1 pathfinder test tanks
SN7 was a pathfinder test article for the SpaceX rocket manufacturing process to switch to type 304L stainless steel from the type 301 stainless steel used for the earlier prototypes. A destructive cryogenic strength test was performed on SN7 on 15 June 2020. The test article achieved pressure of 7.6 bar before it started leaking. The leak caused only limited damage, relative to a burst, which would be a more typical result of this type of test. After repairs, the tank was tested to destruction on 23 June 2020.[failed verification]
By mid July, SpaceX had revealed that it would build a second 304L test tank—this one to have the descriptor SN7.1—which would be tested to destruction and will attempt to achieve a higher tank failure pressure than they achieved with SN7. The tank was tested on several test nights in September, and pushed to fail on 23 September 2020. The tank failed at a pressure of 8 bar near the top of the tank where the tank metal separated.
As of July 2020[update], Starship SN8 is planned to be built out of 304L stainless steel, and is expected to include a nose cone fairing, aerodynamic control surfaces, and three Raptor engines before undertaking higher altitude test flights later in 2020.
Booster prototype 1
On 31 August 2020, Elon Musk stated that the start of the build for "Booster prototype 1" would happen "this week."
Suborbital test flights
|Flight No.||Date and time (UTC)||Vehicle||Launch site||Suborbital apogee||Outcome||Duration|
|1||5 April 2019||Starhopper||Boca Chica, Texas||~ 1 m (3 ft 3 in)||Success||~ 3 seconds|
|Tethered hop which hit tethered limits. With a single Raptor SN2 engine.|
|2||25 July 2019 ||Starhopper||Boca Chica, Texas||20 m (66 ft) ||Success||~ 22 seconds|
|First free flight test. Single Raptor engine, SN6. Was previously scheduled for the day before but was aborted. A test flight attempt on 24 July 2019 was scrubbed.|
|3||27 August 2019 
|Starhopper||Boca Chica, Texas||150 m (490 ft)||Success||~ 57 seconds |
|Single Raptor engine, SN6. SpaceX called this the "150 meter Starhopper Test" on their livestream. Starhopper was retired after this launch, with some parts being reused for other tests. The test flight attempt on 26 August 2019 was scrubbed due to a problem with the Raptor engine igniters.|
|4||4 August 2020
|Starship SN5||Boca Chica, Texas||150 m (490 ft) ||Success ||~ 45 seconds|
|Single Raptor engine, SN27. A successful static fire test was carried out on 30 July 2020. Following 2 separate aborted attempts, a successful 150-meter flight was completed on 4 August 2020.|
|5||3 September 2020
|Starship SN6 ||Boca Chica, Texas||150 m (490 ft) ||Success ||~ 45 seconds|
|Single Raptor engine, SN29. A successful test hop took place on 3 September 2020. A static fire test of SN6 occurred on 24 August 2020 at 00:43 UTC. This also became the shortest duration between test flights, with less than 30 days after SN5's test hop. Elon Musk tweeted later that it was "a much smoother and faster operation" than SN5.|
|6||TBD||Starship SN8 ||Boca Chica, Texas||15 km (9.3 mi) ||Planned|
|Three Raptor engines, SN30, SN32, and SN39. SpaceX conducted a static fire on 20 October 2020, and Musk states that they will then complete another static fire prior to attempting the hop. Unlike previous flights, SN8 has body flaps and a nosecone with front flaps installed.|
|TBD||2022 or 2023||Starship||TBD||TBD||Planned|
|Potential Earth-to-Earth test flight, according to Elon Musk.|
- Launch vehicle system tests
- List of Starship flights
- SpaceX Starship
- SpaceX Mars transportation infrastructure
- Originally designated Mk3 before naming scheme was reset after the failure of Mk1.
- Berger, Eric (29 September 2019). "Elon Musk, Man of Steel, reveals his stainless Starship". Ars Technica. Retrieved 30 September 2019.
- Foust, Jeff (1 September 2020). "Musk emphasizes progress in Starship production over testing". SpaceNews. Retrieved 1 September 2020.
- Lawler, Richard (20 November 2018). "SpaceX BFR has a new name: Starship". Engadget. Retrieved 21 November 2018.
- Sheetz, Michael (7 June 2020). "Elon Musk tells SpaceX employees that its Starship rocket is the top priority now". CNBC. Retrieved 9 June 2020.
- "Huge Mars Colony Eyed by SpaceX Founder". Discovery News. 2012-12-13. Archived from the original on 15 November 2014. Retrieved 2016-09-25.
- Belluscio, Alejandro G. (2014-03-07). "SpaceX advances drive for Mars rocket via Raptor power". NASASpaceFlight.com. Archived from the original on 11 September 2015. Retrieved 2016-09-25.
- Hoffman, Carl (2007-05-22). "Elon Musk Is Betting His Fortune on a Mission Beyond Earth's Orbit". Wired Magazine. Archived from the original on 14 November 2012. Retrieved 2014-03-14.
- "Elon Musk: I'll Put a Man on Mars in 10 Years". Market Watch. New York: The Wall Street Journal. 22 April 2011. Archived from the original on 1 December 2011. Retrieved 1 December 2011.
- Carroll, Rory (2013-07-17). "Elon Musk's mission to Mars". TheGuardian. Archived from the original on 8 January 2014. Retrieved 2016-09-25.
- Messier, Doug (2014-02-05). "Elon Musk Talks ISS Flights, Vladimir Putin and Mars". Parabolic Arc. Archived from the original on 16 September 2018. Retrieved 2016-09-25.
- Zach Rosenberg (15 Oct 2012). "SpaceX aims big with massive new rocket". Flight Global. Archived from the original on 3 July 2015. Retrieved 2016-09-25.
- Coppinger, Rod (2012-11-23). "Huge Mars Colony Eyed by SpaceX Founder Elon Musk". Space.com. Archived from the original on 28 June 2013. Retrieved 2016-09-25.
an evolution of SpaceX's Falcon 9 booster ... much bigger [than Falcon 9], but I don’t think we’re quite ready to state the payload. We’ll speak about that next year. ... Vertical landing is an extremely important breakthrough — extreme, rapid reusability.
- Schaefer, Steve (2013-06-06). "SpaceX IPO Cleared For Launch? Elon Musk Says Hold Your Horses". Forbes. Archived from the original on 6 March 2017. Retrieved 2013-06-10.
- Ciaccia, Chris (2013-06-06). "SpaceX IPO: 'Possible in the Very Long Term'". The Street. Archived from the original on 10 June 2013. Retrieved 2013-06-10.
- Heath, Chris (December 12, 2015). "How Elon Musk Plans on Reinventing the World (and Mars)". GQ. Archived from the original on 12 December 2015. Retrieved 2016-09-25.
- Nellis, Stephen (2014-02-19). "SpaceX's propulsion chief elevates crowd in Santa Barbara". Pacific Coast Business Times. Archived from the original on 26 September 2016. Retrieved 2016-09-25.
- Bergin, Chris (2014-08-29). "Battle of the Heavyweight Rockets -- SLS could face Exploration Class rival". NASAspaceflight.com. Archived from the original on 16 March 2015. Retrieved 2016-11-06.
- Boyle, Alan (5 January 2015). "Coming Soon From SpaceX's Elon Musk: How to Move to Mars". NBC News. Archived from the original on 8 January 2015. Retrieved 2016-09-25.
The Mars transport system will be a completely new architecture. Am hoping to present that towards the end of this year. Good thing we didn't do it sooner, as we have learned a huge amount from Falcon and Dragon.
- Boyle, Alan (2016-01-27). "SpaceX's Elon Musk wants to go into space by 2021 and start Mars missions by 2025". GeekWire. Archived from the original on 30 January 2016. Retrieved 2016-09-25.
- Davenport, Christian (2016-06-13). "Elon Musk provides new details on his 'mind blowing' mission to Mars". Washington Post. Archived from the original on 7 February 2018. Retrieved 2016-09-25.
- Boyle, Alan (2016-06-10). "SpaceX's Elon Musk teases 'dangerous' plan to colonize Mars starting in 2024". GeekWire. Archived from the original on 21 August 2016. Retrieved 2016-08-10.
- Musk, Elon. "Elon Musk @andyzalk". Twitter. Archived from the original on 16 July 2018. Retrieved 2016-09-21.
- Berger, Eric (2016-09-18). "Elon Musk scales up his ambitions, considering going "well beyond" Mars". Ars Technica. Archived from the original on 20 September 2016. Retrieved 2016-09-19.
- Belluscio, Alejandro G. (2016-10-03). "ITS Propulsion – The evolution of the SpaceX Raptor engine". NASASpaceFlight.com. Archived from the original on 22 November 2018. Retrieved 2016-10-03.
- 2016 StartmeupHK Venture Forum - Elon Musk on Entrepreneurship and Innovation. StartmeupHK Venture Forum--2016. via InvestHK YouTube channel: Invest Hong Kong. 26 January 2016. Archived from the original on 28 January 2016. Retrieved 28 January 2016.
(SpaceX discussion at 30:15-31:40) We'll have the next generation rocket and spacecraft, beyond the Falcon and Dragon series ... I'm hoping to describe that architecture later this year at the International Astronautical Congress. which is the big international space event every year. ... first flights to Mars? we're hoping to do that in around 2025 ... nine years from now or thereabouts.
- Boyle, Alan (2016-10-23). "SpaceX's Elon Musk geeks out over Mars interplanetary transport plan on Reddit". GeekWire. Archived from the original on 24 October 2016. Retrieved 2016-10-24.
- Mosher, Dave (2016-11-17). "The 'trickiest' part of Elon Musk's Mars spaceship -- a giant black orb -- just passed a critical test". Business Insider. Archived from the original on 17 November 2016. Retrieved 2016-11-18.
- Elon Musk (19 July 2017). Elon Musk, ISS R&D Conference (video). ISS R&D Conference, Washington DC, USA. Event occurs at 49:48–51:35. Retrieved 13 September 2017 – via YouTube.
the updated version of the Mars architecture: Because it has evolved quite a bit since that last talk. ... The key thing that I figured out is how do you pay for it? If we downsize the Mars vehicle, make it capable of doing Earth-orbit activity as well as Mars activity, maybe we can pay for it by using it for Earth-orbit activity. That is one of the key elements in the new architecture. It is similar to what was shown at IAC, but a little bit smaller. Still big, but this one has a shot at being real on the economic front.
- Musk, Elon (September 17, 2018). First Private Passenger on Lunar BFR Mission. SpaceX. Retrieved September 18, 2018 – via YouTube.
- Bergin, Chris (2015-05-11). "Falcon Heavy enabler for Dragon solar system explorer". NASASpaceFlight.com. Archived from the original on 13 May 2015. Retrieved 12 May 2015.
- Bergin, Chris (2016-09-27). "SpaceX reveals ITS Mars game changer via colonization plan". NASASpaceFlight.com. Archived from the original on 28 September 2016. Retrieved 2016-09-27.
- Richardson, Derek (2016-09-27). "Elon Musk Shows Off Interplanetary Transport System". Spaceflight Insider. Archived from the original on 1 October 2016. Retrieved 2016-10-03.
- "Archived copy". Archived from the original on 27 September 2016. Retrieved 27 September 2016.CS1 maint: archived copy as title (link)
- "Making Humans a Multiplanetary Species" (PDF). SpaceX. 2016-09-27. Archived (PDF) from the original on 20 November 2017. Retrieved 2018-11-10.
- Berger, Eric (2016-09-28). "Musk's Mars moment: Audacity, madness, brilliance—or maybe all three". Ars Technica. Archived from the original on 13 October 2016. Retrieved 2016-10-13.
Foust, Jeff (2016-09-27). "SpaceX's Mars plans call for massive 42-engine reusable rocket". SpaceNews. Retrieved 2016-10-14.
Musk stated it’s possible that the first spaceship would be ready for tests in four years, with the booster ready a few years after that, but he shied away from exact schedules in his presentation. 'We’re kind of being intentionally fuzzy about the timeline,' he said. 'We’re going to try and make as much progress as we can with a very constrained budget.'
- Elon Musk (27 September 2016). Making Humans a Multiplanetary Species (video). IAC67, Guadalajara, Mexico: SpaceX. Event occurs at 9:20–10:10. Archived from the original on 10 October 2016. Retrieved 10 October 2016.
So it is a bit tricky. Because we have to figure out how to improve the cost of the trips to Mars by five million percent ... translates to an improvement of approximately 4 1/2 orders of magnitude. These are the key elements that are needed in order to achieve a 4 1/2 order of magnitude improvement. Most of the improvement would come from full reusability—somewhere between 2 and 2 1/2 orders of magnitude—and then the other 2 orders of magnitude would come from refilling in orbit, propellant production on Mars, and choosing the right propellant.CS1 maint: location (link)
- Elon Musk (29 September 2017). Becoming a Multiplanet Species (video). 68th annual meeting of the International Astronautical Congress in Adelaide, Australia: SpaceX. Retrieved 14 December 2017 – via YouTube.CS1 maint: location (link)
- Musk, Elon (1 March 2018). "Making Life Multi-Planetary". New Space. 6 (1): 2–11. Bibcode:2018NewSp...6....2M. doi:10.1089/space.2018.29013.emu.
- Jeff Foust (29 September 2017). "Musk unveils revised version of giant interplanetary launch system". SpaceNews. Retrieved 1 October 2017.
- Jeff Foust (15 October 2017). "Musk offers more technical details on BFR system". SpaceNews. Retrieved 27 May 2019.
[Musk] added that, since the presentation last month, SpaceX has revised the design of the BFR spaceship to add a "medium area ratio" Raptor engine to its original complement of two engines with sea-level nozzles and four with vacuum nozzles. That additional engine helps enable that engine-out capability ... and will "allow landings with higher payload mass for the Earth to Earth transport function."
- Henry, Caleb (21 November 2017). "SpaceX aims to follow a banner year with an even faster 2018 launch cadence". SpaceNews. Retrieved 15 January 2018.
Shotwell estimated that around 50 percent of the work on BFR is focused on the Raptor engines.
- Foust, Jeff (12 March 2018). "Musk reiterates plans for testing BFR". SpaceNews. Retrieved 15 March 2018.
Construction of the first prototype spaceship is in progress. 'We're actually building that ship right now,' he said. 'I think we'll probably be able to do short flights, short sort of up-and-down flights, probably sometime in the first half of next year.'
- Elon Musk (6 February 2018). 'Crazy things can come true': Elon Musk discusses Falcon Heavy launch: Full presser. Event occurs at 17:00. Archived from the original on 19 February 2019. Retrieved 22 March 2019 – via YouTube.
If we get lucky, we'll be able to do short hopper flights with the spaceship part of BFR maybe next year.
- Masunaga, Samantha (2018-04-19). "SpaceX gets approval to develop its BFR rocket and spaceship at Port of Los Angeles". Los Angeles Times. Archived from the original on 21 April 2018. Retrieved 2018-04-21.
- Berger, Eric (19 March 2018). "SpaceX indicates it will manufacture the BFR rocket in Los Angeles". Ars Technica. Archived from the original on 21 March 2018. Retrieved 21 March 2018.
- "Fireside Chat with SpaceX President Gwynne Shotwell". Flickr.com. 11 October 2017. Archived from the original on 5 April 2019. Retrieved 7 March 2018.
- Seemangal, Robin (1 February 2018). "SpaceX Gears Up to Finally, Actually Launch the Falcon Heavy". Wired. Archived from the original on 25 February 2018. Retrieved 7 March 2018.
SpaceX is actively considering expanding its San Pedro, California facility to begin manufacturing its interplanetary spacecraft. This would allow SpaceX to easily shift personnel from headquarters in Hawthorne.
- Masunaga, Samantha (8 May 2018). "All systems are go for SpaceX's BFR rocket facility at Port of Los Angeles after City Council OKs plan". Los Angeles Times. Archived from the original on 24 May 2018. Retrieved 24 May 2018.
- "Regular Meeting, Planning & Strategy, Resolution" (PDF). Port of Los Angeles. Archived from the original (PDF) on 12 June 2018. Retrieved 6 June 2018.
- Insinnia, Valerie (2 August 2018). "One possible job for SpaceX's BFR rocket? Taking the Air Force's cargo in and out of space". DefenseNews. Retrieved 9 June 2019.
- Air Mobility Command Chief Looks Toward Supplying Forces From Space Archived 9 June 2019 at the Wayback Machine, US Department of Defense, 2 August 2018.
- "Elon Musk Says SpaceX Will Send Yusaku Maezawa (and Artists!) to the Moon". Wired. 18 September 2018. Archived from the original on 16 July 2019. Retrieved 27 May 2019.
- Eric Ralph (14 September 2018). "SpaceX has signed a private passenger for the first BFR launch around the Moon". Archived from the original on 14 September 2018. Retrieved 14 September 2018.
- Foust, Jeff (17 November 2018). "Musk hints at further changes in BFR design". SpaceNews. Retrieved 22 March 2019.
- Boyle, Alan (19 November 2018). "Goodbye, BFR … hello, Starship: Elon Musk gives a classic name to his Mars spaceship". GeekWire. Archived from the original on 22 November 2018. Retrieved 22 November 2018.
Starship is the spaceship/upper stage & Super Heavy is the rocket booster needed to escape Earth's deep gravity well (not needed for other planets or moons)
- Elon Musk on Twitter: 3 sea level optimized Raptors, 3 vacuum optimized Raptors (big nozzle)
- Musk, Elon (17 March 2019). "Full size".
- Musk, Elon (23 May 2019). "First flights would have fewer, so as to risk less loss of hardware. Probably around 20".
- "Elon Musk: Super Heavy will have 31 engines, not 37". Twitter. Retrieved 3 May 2020.
- Elon Musk [@elonmusk] (27 August 2020). "Neuralink this month & Tesla next month, SpaceX probably October. We will have made a lot of progress by then. Might have a prototype booster hop done by then" (Tweet). Retrieved 23 September 2020 – via Twitter.
- "SpaceX Starship hardware mystery solved amid reports of Florida factory upheaval". 2 December 2019.
- Ralph, Eric (2020-07-17). "SpaceX scraps Florida Starship Mk2 prototype". TESLARATI. Retrieved 2020-09-04.
- Ralph, Eric (2019-10-18). "SpaceX's fourth Starship prototype has begun to take shape in Florida". Retrieved 2020-04-04.
- Elon Musk on Twitter: We’re now building flight design of Starship SN1, but each SN will have at least minor improvements, at least through SN20 or so of Starship V1.0.
- "SpaceX's Starship SN1 prototype appears to burst during pressure test". Retrieved 1 March 2020.
- March 2020, Mike Wall 10. "SpaceX's latest Starship prototype passes big tank pressure test". Space.com. Retrieved 2020-04-02.
- "Starship SN3 failure due to bad commanding. SN4 already under construction". NASASpaceFlight.com. 2020-04-05. Retrieved 2020-04-19.
- "Third Starship prototype destroyed in tanking test". SpaceNews.com. 2020-04-03. Retrieved 2020-04-04.
- Ralph, Eric (2020-06-02). "SpaceX's Starship explosion explained by Elon Musk". Teslarati. Retrieved 2020-06-05.
- Foust, Jeff (29 May 2020). "SpaceX Starship prototype destroyed after static-fire test". SpaceNews. Retrieved 30 May 2020.
- Malik, Tariq (29 May 2020). "SpaceX's Starship SN4 prototype explodes after rocket engine test". Space.com. Retrieved 23 September 2020.
- Ralph, Eric (12 May 2020). "SpaceX's first high-flying, triple-Raptor Starship is almost finished". Teslarati. Retrieved 12 May 2020.
- Baylor, Michael (3 August 2020). "Starship SN5 conducts successful 150-meter flight test". NASASpaceFlight. Retrieved 6 August 2020.
- @elonmusk (8 Aug 2020). "[In regards to the future flight of SN5] Not sure yet, but hopefully. Will need leg & other repairs. Probably SN6 flies before SN5. We need to make flights simple & easy — many per day" (Tweet) – via Twitter. Cite error: The named reference "musk20200808" was defined multiple times with different content (see the help page).
- "SpaceX tests a Starship dome tank at SpaceX Boca Chica". TESMANIAN.
- Baylor, Michael (5 June 2020). "SpaceX set for a swift return to testing following Starship SN4 anomaly". NASASpaceFlight.com. Retrieved 6 June 2020.
- @RGVaerialphotos (23 June 2020). "SN7 aftermath from an aerial perspective!" (Tweet) – via Twitter.
- SN 7.1 tank section photos, construction in progress
- @elonmusk (11 August 2020). "SN7 will be new alloy test tank taken to burst pressure" (Tweet) – via Twitter.
- SN 9 progress
- SN10 progress
- SN11 progress
- [https://twitter.com/brendan2908/status/1311772761069477893 SH SN1 progress
- SN12 progress
- Elon Musk [@elonmusk] (8 December 2018). "The new design is metal" (Tweet) – via Twitter.
- Elon Musk [@elonmusk] (8 December 2018). "Fairly heavy metal, but extremely strong" (Tweet) – via Twitter.
- Ralph, Eric (9 December 2018). "SpaceX CEO Elon Musk teases new Starship photos and "heavy metal" BFR". Teslarati. Archived from the original on 9 December 2018. Retrieved 9 December 2018.
wide-reaching changes to BFR’s general structural composite, Musk at long last confirmed what some had suspected – now known as the Starship/Super Heavy — the BFR program has officially moved away from carbon fiber composites as the primary material of choice for the rocket's structure and propellant tanks, instead pivoting to what Musk described as a "fairly heavy metal".
- D'Agostino, Ryan (22 January 2019). "Elon Musk: Why I'm Building the Starship out of Stainless Steel". Popular Mechanics. Retrieved 30 May 2019.
- Commercial Space Transportation Experimental Permit -- Experimental Permit Number: EP19-012, FAA, 21 June 2019, accessed 29 June 2019.
- Ralph, Eric (12 March 2019). "SpaceX begins static Starhopper tests as Raptor engine arrives on schedule". Teslarati. Retrieved 22 March 2019.
- Gebhardt, Chris (18 March 2019). "Starhopper first flight as early as this week; Starship/Superheavy updates". NASASpaceFlight.com. Retrieved 22 March 2019.
- D'Agostino, Ryan (January 22, 2019). "Elon Musk: Why I'm Building the Starship out of Stainless Steel". popularmechanics.com. Popular Mechanics. Archived from the original on 22 January 2019. Retrieved January 22, 2019.
- Berger, Eric (15 May 2019). "SpaceX plans to A/B test its Starship rocketship builds". Ars Technica. Retrieved 16 December 2019.
- Gray, Tyler (28 May 2019). "SpaceX ramps up operations in South Texas as Hopper tests loom". NASASpaceFlight.com. Retrieved 30 May 2019.
- Baylor, Michael (17 May 2019). "SpaceX considering SSTO Starship launches from Pad 39A". NASASpaceFlight. Retrieved 16 December 2019.
- Ralph, Eric (24 December 2018). "SpaceX CEO Elon Musk: Starship prototype to have 3 Raptors and "mirror finish"". Teslarati. Archived from the original on 24 December 2018. Retrieved 24 December 2018.
- Foust, Jeff (24 December 2018). "Musk teases new details about redesigned next-generation launch system". SpaceNews. Retrieved 25 December 2018.
- 'Totally Nuts'? Elon Musk Aims to Put a Starship in Orbit in 6 Months. Here's SpaceX's Plan. Mike Wall, Space.com. 30 September 2019.
- Elon Musk [@elonmusk] (30 May 2019). "Wings/flaps & leg design changing again (sigh). Doesn't affect schedule much though" (Tweet) – via Twitter.
- Elon Musk [@elonmusk] (22 September 2019). "Adding the rear moving fins to Starship Mk1 in Boca Chica, Texas" (Tweet) – via Twitter.
- SpaceX installs two Starship wings ahead of Elon Musk’s Saturday update. Eric Ralph, TeslaRati. 22 September 2019.
- Elon Musk tweets a sneak peek at his vision for SpaceX’s Starship mega-rocket. Alan Boyle, GeekWire. 22 September 2019.
- Berger, Eric (2019-07-26). "SpaceX's Starship prototype has taken flight for the first time". Ars Technica. Retrieved 8 August 2019.
- Foust, Jeff (2019-08-27). "SpaceX's Starhopper completes test flight". SpaceNews. Retrieved 28 August 2019.
- Elon Musk (28 September 2019). Starship Update (video). SpaceX. Event occurs at 1:45. Retrieved 30 September 2019 – via YouTube.
- Malik, Tariq (28 September 2019). "Elon Musk Unveils SpaceX's New Starship Plans for Private Trips to the Moon, Mars and Beyond". Space.com. Retrieved 29 September 2019.
- Zafar, Ramish (28 September 2019). "SpaceX's Starship Mk1 Expected To Be Ready For 20km Test In 2 Months". wccftech.com. Retrieved 29 September 2019.
- Matsunaga, Samantha (28 September 2019). "Five things we learned from Elon Musk's rollout of the SpaceX Starship prototype". Los Angeles Times. Retrieved 29 September 2019.
- "SpaceX's Starship is a new kind of rocket, in every sense". The Economist. 5 October 2019. Retrieved 23 November 2019.
- Wall, Mike (30 September 2019). "'Totally Nuts'? Elon Musk Aims to Put a Starship in Orbit in 6 Months. Here's SpaceX's Plan". Space.com. Retrieved 23 November 2019.
- Grush, Loren (20 November 2019). "SpaceX's prototype Starship rocket partially bursts during testing in Texas". The Verge. Retrieved 10 March 2020.
- Marley, Ronnie (20 November 2019). "SpaceX moving to MK3 vehicle following incident at Boca Chica Facility". CBS News. Retrieved 10 March 2020.
- Wall, Mike (20 November 2019). "SpaceX's 1st Full-Size Starship Prototype Suffers Anomaly in Pressure Test". Space.com. Retrieved 21 November 2019.
- Sheetz, Michael (17 October 2019). "Aerial video shows SpaceX beginning construction of another Starship rocket in Florida". CNBC. Retrieved 18 October 2019.
- Ralph, Eric (2 December 2019). "SpaceX Starship hardware mystery solved amid reports of Florida factory upheaval". Retrieved 2 December 2019.
- @elonmusk (22 September 2019). "Mk1 ship is around 200 tons dry & 1400 tons wet, but aiming for 120 by Mk4 or Mk5. Total stack mass with max payload is 5000 tons" (Tweet) – via Twitter.
- Elon Musk [@elonmusk] (22 September 2019). "For aero control, it comes down to % of cross-sectional area moving vs not. Flexible as to whether front or rear, so long as within bounds of center of mass & pressure" (Tweet) – via Twitter.
- Elon Musk [@elonmusk] (22 September 2019). "Nose tip has forward movable fins, cold gas attitude control thrusters, header tanks for landing, composite pressure vessels, several large batteries, etc. Placed up there to balance high mass of Raptors & rear fins at the bottom" (Tweet) – via Twitter.
- Elon Musk [@elonmusk] (22 September 2019). "Stability is controlled by (very) rapid movement of rear & fwd fins during entry & landing, as well as ACS thrusters. The smaller leeward "fin" would simply be used as a leg" (Tweet) – via Twitter.
- Elon Musk [@elonmusk] (24 September 2019). "Many powerful electric motors & batteries. Force required is enormous, as entire fin moves. More about this on the 28th" (Tweet) – via Twitter.
- A conversation with Elon Musk about Starship, The Everyday Astronaut, 1 October 2019.
- Baylor, Michael (2 June 2019). "SpaceX readying Starhopper for hops in Texas as Pad 39A plans materialize in Florida". NASASpaceFlight.com. Retrieved 3 June 2019.
- Musk, Elon (2019-12-29). "Almost everything is different. These parts are stamped vs manually bump-formed & TIP TIG welded vs flux core. Higher precision, stronger joints & 20% mass reduction". Twitter. Retrieved 2020-01-22.
- "SpaceX is ready to build the first Starship destined for space after latest tests".
- "SpaceX just blew up a Starship tank on purpose and Elon Musk says the results are in".
- January 2020, Hanneke Weitering 30. "SpaceX just destroyed a huge tank for its Starship on purpose. Here's the video!". Space.com.
- Baylor, Michael (19 February 2020). "SpaceX beginning final assembly of Starship SN1 ahead of roll to the pad". NASASpaceFlight. Retrieved 10 March 2020.
- Baylor, Michael (3 December 2019). "SpaceX expediting Mk3 construction in Texas, pausing Florida-based Starship builds". NASASpaceFlight. Retrieved 10 March 2020.
- Wall, Mike (10 March 2020). "SpaceX's latest Starship prototype passes big tank pressure test". Space.com. Retrieved 10 March 2020.
- Foust, Jeff (1 March 2020). "Second Starship prototype damaged in pressurization test". SpaceNews. Retrieved 10 March 2020.
- "Starship SN3 failure due to bad commanding. SN4 already under construction". April 5, 2020.
- "r/spacex - SN3 Fails during cryogenic testing" – via www.reddit.com.
- "Starship SN3 failure due to bad commanding. SN4 already under construction". NASASpaceFlight.com. 2020-04-05. Retrieved 2020-04-19.
- Ralph, Eric (2020-04-17). "SpaceX is about to reuse (part of) a Starship rocket". TESLARATI. Retrieved 2020-04-19.
- Baylor, Michael (26 April 2020). "SN4 becomes first full-scale Starship prototype to pass cryogenic proof test". NASASpaceFlight. Retrieved 23 September 2020.
- Arevalo, Evelyn (9 May 2020). "SpaceX completes another round of Starship tests at Boca Chica". Tesmanian. Retrieved 23 September 2020.
- "SpaceX Starship prototype charred but intact after catching fire [photos]".
- Berger, Eric (5 March 2020). "Inside Elon Musk's plan to build one Starship a week—and settle Mars". Ars Technica. Retrieved 10 March 2020.
- Bergin, Chris (27 July 2020). "Starship SN5 completes successful Static Fire test". NASASpaceFlight.com. Retrieved 4 August 2020.
- "SpaceX Successfully Flies its Starship Prototype to a Height of Around 500 Feet". 8 August 2020.
- Baylor, Michael (15 July 2020). "Starship SN5 set for a static fire followed shortly by a 150-meter hop attempt". NASASpaceFlight. Retrieved 17 July 2020.
The most recent test tank, designated SN7, achieved a record pressure before it failed. SN7 was the pathfinder vehicle for the switch to 304L stainless steel. The next test tank – designated SN7.1 – will feature further build-quality improvements, as it attempts to break the record set by SN7.
- Starship's SN7.1 Pushed To Failure (Time Lapse), LabPadre channel, 23 September 2020, retrieved 27 September 2020.
- 8 bar differential in ullage, 9 bar at base due to propellant head. It’s enough. Improvements in work., Elon Musk, 26 September 2020, retrieved 27 September 2020.
- Berger, Eric (26 July 2019). "SpaceX.s Starship prototype has taken flight for the first time". Ars Technica. Retrieved 26 July 2019.
- Burghardt, Thomas (25 July 2019). "Starhopper successfully conducts debut Boca Chica Hop". NASASpaceFlight.com. Retrieved 26 July 2019.
- Ralph, Eric (27 August 2019). "SpaceX scrubs Starhopper.s final Raptor-powered flight as Elon Musk talks finicky igniters". Teslarati. Retrieved 27 August 2019.
- Baylor, Michael (27 August 2019). "SpaceX's Starhopper completes 150 meter test hop". NASASpaceFlight. Retrieved 27 August 2019.
- "SpaceX Starhopper Rocket Prototype Aces Highest (and Final) Test Flight". space.com. Retrieved 29 August 2019.
- 150 Meter Starhopper Test. SpaceX. 27 August 2019. Retrieved 27 August 2019 – via YouTube.
- Mosher, Dave (7 August 2019). "SpaceX may cannibalize its first Mars rocket-ship prototype in Elon Musk's race to launch Starship". Business Insider. Retrieved 27 August 2019.
- Ralph, Eric (4 August 2020). "SpaceX Starship leaps towards Mars with picture-perfect hop debut". Teslarati. Retrieved 4 August 2020.
- @NASASpaceflight (4 August 2020). "LAUNCH! Starship SN5 has launched on a 150 meter test hop at SpaceX Boca Chica" (Tweet) – via Twitter.
- Baylor, Michael (4 August 2020). "Starship SN5 conducts successful 150-meter flight test". NASASpaceflight. Retrieved 4 August 2020.
- @elonmusk (30 July 2020). "Starship SN5 just completed full duration static fire. 150m hop soon" (Tweet) – via Twitter.
- @thesheetztweetz (30 July 2020). "SpaceX test fires its Starship prototype SN5" (Tweet) – via Twitter.
- Clark, Stephen (5 August 2020). "SpaceX clears big hurdle on next-gen Starship rocket program". Spaceflight Now. Retrieved 5 August 2020.
- @NASASpaceflight (3 September 2020). "IGNITION! Starship SN6 Hop Test! Under the power of Raptor SN29, SN6 has completed a near-mirror test of SN5's hop! SUCCESS Again!" (Tweet) – via Twitter.
- "SN6 begins test campaign as future Starships hatch plans for SpaceX's next leap". nasaspaceflight.com. August 16, 2020.
- @elonmusk (3 September 2020). "Starship SN6 flew asimilar hop to SN5, but it was a much smoother and faster operation" (Tweet) – via Twitter.
- @NASASpaceflight (23 August 2020). "STATIC FIRE! Starship SN6 fires up Raptor SN29 at Boca Chica!" (Tweet) – via Twitter.
- @elonmusk (12 September 2020). "SN8 Starship with flaps and nosecone should be done in about a week. Then static fire, checkouts, static fire, fly to 60,000 ft and back" (Tweet) – via Twitter.
- @elonmusk (26 September 2020). "Nosecone and front flaps next week. SN9 next month. First flight is to 15 km or ~50,000 ft" (Tweet) – via Twitter.
- Bergin, Chris (18 October 2020). "Starship SN8 pressing to Static Fire and nosecone installation firsts". NASASpaceflight. Retrieved 18 October 2020.
- @elonmusk (14 October 2020). "Will be less roomy with 3 vacuum rocket engines added [Image of the bottom of SN8 with 3 raptors installed]" (Tweet) – via Twitter.
- Ralph, Eric (20 October 2020). "SpaceX Starship fires up three Raptor engines in prelude to high-altitude flight". Teslarati. Retrieved 10 October 2020.
- SpaceX Boca Chica - First Super Heavy Booster Parts - SN8 Flaps Installed.
- @BocaChicaGal (22 October 2020). "A beautiful sky behind a fully stacked Starship. SN8 you are beautiful" (Tweet) – via Twitter.
- Mosher, Dave (16 June 2020). "Elon Musk: "SpaceX is building floating, superheavy-class spaceports" for its Starship rocket to reach the Moon, Mars, and fly passengers around Earth". Business Insider. Archived from the original on 17 June 2020. Retrieved 16 June 2020.