SpaceX Starship

Starship

Starship/Super Heavy vehicle during Orbital Flight Test
Function	sub-orbital spaceflight orbital spaceflight interplanetary spaceflight
Manufacturer	SpaceX
Country of origin	United States
Cost per launch	< $100 million (est.)
Size
Height	121.3 m 398 ft
Diameter	9 m 29.5 ft
Mass	5,000 t 11,000,000 lb
Capacity
Payload to low Earth orbit
Mass	150 t 330,000 lb
Volume	1,000 m³ 35,000 ft³
Note:
Launch history
Launch sites	SpaceX Starbase Kennedy Space Center, LC-39A (planned)
Total launches	1
Success(es)	0
Partial failure(s)	1
First flight	20 April 2023
First stage – Super Heavy
Height	71 m 232 ft
Diameter	9 m 30 ft
Empty mass	200 t 440,000 lb
Propellant mass	3,400 t 7,500,000 lb
Powered by	Raptor engine (33)
Maximum thrust	7,590 Tf 74,500,000 N 16,700,000 lbf
Propellant	liquid oxygen liquid methane
Second stage – Starship
Height	50 m 164 ft
Diameter	9 m 30 ft
Empty mass	100 t 220,000 lb
Gross mass	1,300 t 2,900,000 lb
Propellant mass	1,200 t 2,650,000 lb
Powered by	Raptor engine (3) Raptor Vacuum (3)
Maximum thrust	14,700,000 N 1,500 Tf 3,300,000 lbf
Propellant	liquid oxygen liquid methane

Starship is a super heavy-lift space launch vehicle under development by SpaceX. At 120 m (390 ft) in height and with a liftoff mass of 5,000 metric tons (11,000,000 lb), Starship is the largest and most powerful launch vehicle ever flown, and the first intended to be fully reusable.

The Starship launch vehicle consists of the first stage Super Heavy booster and the second stage Starship spacecraft. Both stages are powered by the Raptor rocket engine, which burns liquid oxygen and liquid methane propellants in a highly complex but efficient full-flow staged combustion power cycle. Both rocket stages are designed to be reusable, performing controlled landings on the launch tower and reflown within hours. Starship is planned to have a payload capacity of 150 t (330,000 lb) to low Earth orbit in a fully reusable configuration and 250 t (550,000 lb) when expended. Starship vehicles in low Earth orbit can be refilled with propellant launched in other tanker Starships to enable transit to higher energy destinations such as geosynchronous orbit, the Moon, and Mars.

Plans for a heavy lift vehicle at SpaceX date back to 2005, with the earliest concept resembling the modern vehicle announced in 2016. Starship development follows an iterative and incremental approach involving frequent—and often destructive—test flights of incomplete vehicles. The first orbital test flight attempt, on April 20, 2023, ended after the vehicle was destroyed four minutes into its flight.

SpaceX plans for Starship to eventually become its primary launch vehicle, superseding the existing fleet of Falcon 9, Falcon Heavy and Dragon spacecraft, and is often coupled with the company's Mars ambitions. Planned Starship flights include the build-out of SpaceX's Starlink internet constellation, crewed flights under the Polaris and dearMoon programs, and a crewed lunar landing with a modified Starship spacecraft under the Artemis program.

Background

Further information: History of SpaceX, SpaceX reusable launch system development program, and SpaceX Starship development

In November 2005, prior to SpaceX's first orbital launch attempt, CEO Elon Musk first mentioned a heavy-lift launch vehicle concept named BFR with a payload of 100 t (220,000 lb) to low Earth orbit. The vehicle would be powered by Merlin 2, a scaled-up version of the Merlin engine. 2009 would see the first public mention of a rocket engine named Raptor, then a hydrogen-oxygen upper stage engine, but it would remain a low-priority project for several years. In July 2010, shortly after Falcon 9 took flight, SpaceX announced plans for the development of Merlin 2-powered launch vehicles with performance comparable to that of the Saturn V for its "ultimate goal" of reaching Mars.

Illustration of the Interplanetary Transport System, 2016

Around 2015, Musk teased about the Mars Colonial Transporter, a proposed rocket for Mars colonization powered by the now methane-oxygen Raptor engine then under development. A prototype Raptor engine was fired on the test stand for the first time on 26 September 2016. Days later at the International Astronautical Congress, Elon Musk announced the Interplanetary Transport System, a concept for a fully reusable two-stage launch vehicle using the Raptor engine capable of lifting 300 t (660,000 lb) to low Earth orbit while reusing both stages. To transport crew to Mars, propellant tanker vehicles would refuel crew vehicles in Earth orbit prior to departure. At the time, Musk noted that SpaceX had no concrete plans to finance the immense capital cost of developing the vehicle and transportation system for Mars colonization.

Illustration of the Big Falcon Rocket, 2018

One year later at the following IAC, Elon Musk presented a scaled-down, 150 t (330,000 lb) capacity concept, again under the BFR moniker ("Big F---ing Rocket", adopted as "Big Falcon Rocket"), which would be used for revenue-generating activities such as satellite launch, International Space Station resupply, and point-to-point travel on Earth, in addition to interplanetary passenger transport. In April 2018, the mayor of Los Angeles confirmed plans for a BFR rocket production facility at the Port of Los Angeles.

In January 2019 Elon Musk announced that the vehicle would be constructed out of stainless steel instead of carbon composites. Musk explained, despite the heavier weight, stainless steel possesses superior strength in both cryogenic and high-temperature environments while being much less expensive and more workable than carbon composites; "counterintuitive[ly]" resulting in a lighter vehicle as a result. Previously constructed carbon composite tooling was scrapped, and the Port of Los Angeles facility would be abandoned the following year.

In September 2018, the BFR spacecraft was redesigned to include actuating "body flaps" that served as control surfaces during descent; two forward flaps and three larger aft flaps that also served as landing legs. Around the same time, SpaceX announced that billionaire Yusaku Maezawa, who had previously contracted for a space tourism mission with the company, would fly onboard BFR on a flight around the Moon. This contract secured additional funding for the rocket's development. The names 'Starship' for the system and second stage and 'Super Heavy' for the booster were announced in November 2018.

Development

Main article: SpaceX Starship development

Starship's development is iterative and incremental, using intensive tests on a series of rocket prototypes. The first prototype, Starhopper, performed several static fires and low-altitude flights. Seven of Starship's upper stage prototypes were flight tested between August 2020 and May 2021. The last of the seven, a full-size Starship SN15, successfully landed after reaching an altitude of 10 kilometers (6.2 mi). A full-scale orbital test flight of the rocket took place on April 20, 2023.

Starship prototype tests can generally be classified into three main types. In proof pressure tests, the vehicle's tanks are pressurized with either gases or liquids to test their strength—sometimes deliberately until they burst. The vehicle then performs mission rehearsals, with or without propellant, to check the vehicle and ground infrastructure. Before a test flight, SpaceX loads the vehicle prototype with propellant and briefly fires its engines in a static fire test. Alternatively, the engines' turbopump spinning can be tested without firing the engines, referred to as a spin prime test.

After successful testing, uncrewed flight tests and launches may commence. During a suborbital launch, Starship prototypes fly to a high altitude and descend, landing either near the launch site, in the sea, or onto offshore platforms. During an orbital launch, Starship performs procedures as described in its mission profile. Due to SpaceX's relative openness for outsiders to peer into the facilities, Starship rocket tests, flights, and launches have received significant media coverage.

Low-altitude flights

Starhopper under construction, March 2019

A crane lifting Starship SN5, August 2020

In September 2019, Musk further detailed the lower-stage booster, the upper stage's method of controlling its descent, its heat shield, orbital refueling capacity, and potential destinations besides Mars. The aft flaps on the spacecraft were reduced from three to two, and Starship's body material was changed from carbon composites to stainless steel for its lower cost, higher melting point, strength at cryogenic temperatures, and ease of manufacture.

SpaceX was already constructing the first full-size Starship Mk1 and Mk2 upper-stage prototypes, at the SpaceX facilities in Boca Chica, Texas and Cocoa, Florida respectively. Neither prototype flew: Mk1 was destroyed in November 2019 during a pressure stress test and Mk2's Florida facility was abandoned and deconstructed throughout 2020. After the Mk prototypes, SpaceX began naming its new Starship upper-stage prototypes with the prefix "SN", short for "serial number". No prototypes between SN1 and SN4 flew either—SN1 and SN3 collapsed during pressure stress tests, and SN4 exploded after its fifth engine firing.

In June 2020, SpaceX started construction of a launch pad for orbit-capable Starship rockets. In the next month, the company bought two drilling rigs for $3.5 million each from Valaris plc during the latter's bankruptcy proceedings, to repurpose them as offshore spaceports. The first flight-capable Starship SN5 was cylindrical as it had no flaps or nose cone: just one Raptor engine, propellant tanks, and a mass simulator. On 5 August 2020, SN5 performed a 150 m (500 ft) high flight and successfully landed on a nearby pad. On 3 September 2020, the similar-looking Starship SN6 repeated the hop; later that month, the Raptor Vacuum engine was fired in full duration.

High-altitude flights

Starship SN9 on a mount with its flaps closed, January 2021

SN8 was the first fully complete Starship upper stage prototype. It underwent four preliminary static fire tests between October and November 2020. On 9 December 2020, SN8 flew, slowly turning off its three engines one by one, and reached an altitude of 12.5 km (7.8 mi). After SN8 dove back to the ground, its engines were hampered by low methane header tank pressure during the landing attempt, which led to a hard impact with the landing pad. 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.

On 2 February 2021, Starship SN9 launched to 10 km (6.2 mi) in a flight path similar to SN8. The prototype crashed upon landing because one of its engines did not properly ignite. A month later, on 3 March, Starship SN10 launched on the same flight path as SN8 and 9. The vehicle landed hard and crushed its landing legs, leaning to one side, and a fire was seen at the vehicle's base. It exploded less than ten minutes later, probably due to a propellant tank rupture. On 30 March, Starship SN11 flew into thick fog along the same flight path. The vehicle exploded during descent, possibly due to excess propellant in a Raptor's methane turbopump.

In March 2021, the company disclosed a public construction plan for two sub-orbital launch pads, two orbital launch pads, two landing pads, two test stands, and a large propellant tank farm. The company soon proposed developing the surrounding Boca Chica village into a company town named Starbase; locals raised concerns about SpaceX's authority, power, and potential threat for eviction through eminent domain. In early April, the orbital launch pad's fuel storage tanks began mounting. A few weeks later, on 16 April, NASA selected Starship Human Landing System (HLS) as the crewed lunar lander. Blue Origin, a bidding competitor to SpaceX, disputed the decision and began a legal case in August 2021, which was dismissed by the Court of Federal Claims three months later.

Starship prototypes SN12, SN13, and SN14 were scrapped before completion; SN15 was selected to fly instead. SN15 had better avionics, structure, and engines. On 5 May 2021, SN15 launched, completed the same maneuvers as older prototypes, and landed safely. Even though SN15, like SN10, had a small fire in the engine area after landing, it was extinguished, completing the first successful high-altitude test. According to a later report by SpaceX, SN15 experienced several issues while landing, including the loss of tank pressure and an engine.

Development towards the first orbital launch

From left to right: Booster 4, Ship 15, Ship 22, and Ship 20 displayed at Starbase, June 2022

In July 2021, Super Heavy BN3 conducted its first full-duration static firing and lit three engines. Around this time, SpaceX changed their naming scheme from "SN" to "Ship" for Starship crafts, and from "BN" to "Booster" for Super Heavy boosters. A month later, using cranes, Ship 20 was stacked atop Booster 4 to form the full launch vehicle for the first time; Ship 20 was also the first craft to have a body-tall heat shield. In October 2021, the catching mechanical arms, also known as "chopsticks", were installed onto the integration tower and the first tank farm's construction was completed. Two weeks later, NASA and SpaceX announced plans to construct Kennedy Space Center's Launch Complex 49.

The Raptor 2 engine was spotted by the public at the start of 2022. Raptor 2 has a simpler design, less mass, wider throat, and an increase in main combustion chamber pressure from 250 bar (3,600 psi) to 300 bar (4,400 psi). These changes yielded an increase in thrust from 1.85 MN (420,000 lbf) to 2.3 MN (520,000 lbf), but a decrease of 3 seconds (~0.9%) of specific impulse. In February 2022, after stacking Ship 20 on top of Booster 4 using mechanical arms, Elon Musk gave a presentation on Starship, Raptor engine and Florida spaceport development at Starbase.

In June 2022, the Federal Aviation Administration determined that Starbase did not need a full environmental impact assessment, but that SpaceX must address issues identified in the preliminary environmental assessment. In July, Booster 7 tested spinning the liquid oxygen turbopumps on all thirty-three Raptor engines, and an explosion occurred at the base of the vehicle, destroying a pressure pipe and causing minor damage to the launchpad. By the end of November, Ship 24 had performed 2- and full 6-engine static fires, while Booster 7 had performed static fires with 1, 3, 7, 11, and 14 engines and finally on 9th February 2023 a static fire with 31 engines at 50% throttle (33 was attempted but one engine was disabled pre-firing, and another engine aborted). In January 2023, Starship underwent a full wet dress rehearsal at Starbase, where it was filled with more than 4,500 t (10,000,000 lb) of propellant.

First attempted orbital test flight

Main article: SpaceX Starship orbital test flight

Ship 24/Booster 7 stack at the first attempted Starship orbital launch, April 2023

After a cancelled launch attempt on April 17 due to a frozen valve, Booster 7 and Ship 24 lifted off on 20 April 2023 at 14:33 UTC in the first orbital flight test that ended in failure. Even though it lost several engines through the spaceflight, the vehicle reached a maximum altitude of 39 km (24 mi). The spacecraft was unable to separate from the booster and the rocket was intentionally destroyed by commanding the flight termination system. Had everything proceeded as planned, the spacecraft would have continued to fly with its ground track passing through the Straits of Florida, with a hard splashdown in the Pacific Ocean around 100 km (60 mi) northwest of Kauai in the Hawaiian Islands, having made nearly one revolution around the Earth.

Design

Stacked and fueled, Starship is about 5,000 t (11,000,000 lb) by mass, 9 m (30 ft) wide, and 120 m (390 ft) high. While the prototype versions of Starship are not reused, Starship is designed to be a fully reusable and orbital rocket, to reduce launch costs and maintenance between flights. Its fully reusable configuration has a payload capacity of 150 t (330,000 lb) to low Earth orbit and the expanded configuration has a payload capacity of 250 t (550,000 lb).

The rocket will consist of a Super Heavy first stage or a booster and a Starship second stage or spacecraft, powered by Raptor and Raptor Vacuum engines. The bodies of both rocket stages are made from stainless steel, giving Starship its strength for atmospheric entry and distinctive look.

According to Eric Berger of Ars Technica, the manufacturing process starts with rolls of steel, which are unrolled, cut, and welded along the cut edge to create a cylinder 9 m (30 ft) in diameter, 2 m (7 ft) in height, and around 1,600 kg (4,000 lb) in mass. These cylinders, along with the nose cones, are stacked and welded along their edges to form the outer layer of the rocket. Inside, the methane and oxygen tanks are separated by the robot-made domes. Also according to Berger, Starship's reusability and stainless-steel construction has influenced the Terran R rocket and Project Jarvis's second stage.

Raptor engine

Main article: SpaceX Raptor

Sea level–optimized Raptor engine, May 2020

Raptor is a family of rocket engines developed by SpaceX exclusively for use in Starship and Super Heavy. It burns liquid oxygen and methane in a highly efficient full-flow staged combustion power cycle. The Raptor engine uses methane as the fuel of choice over other rocket propellants, because methane produces less soot and can be directly synthesized from carbon dioxide and water.

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. Raptor's main combustion chamber can contain 300 bar (4,400 psi) of pressure, the highest of all rocket engines. Certain components are 3D printed. The Raptor's gimbaling range is 15°, higher than the RS-25's 12.5° and the Merlin's 5°. In mass production, SpaceX aims to produce each engine at a unit cost of US$250,000.

Raptor operates with an oxygen-to-methane mixture ratio of about 3.6:1, lower than the stoichiometric mixture ratio of 4:1 necessary to completely burn all propellants. Operation at the stoichiometric ratio provides better performance in theory, but in practice usually results in overheating and destruction of the engine. The propellants leave the pre-burners and are injected into the main combustion chamber as hot gases instead of liquid droplets, enabling much higher power density as propellants mix rapidly via diffusion. The methane and oxygen are at such high temperatures and pressures that they ignite on contact, eliminating the need for igniters in the main combustion chamber.

At sea level, the standard Raptor engine produces 2.3 MN (520,000 lbf) at a specific impulse of 327 seconds, increasing to 350 seconds in a vacuum. Raptor Vacuum, used on the Starship upper stage, is modified with a regeneratively cooled nozzle extension made of brazed steel tubes, increasing its expansion ratio to about 90 and its specific impulse in a vacuum to 380 seconds. Another engine variant, Raptor Boost, is exclusive to the Super Heavy booster; the engine variant lacks thrust vectoring and has limited throttle capability, in exchange for increased thrust.

Super Heavy booster

Underside of Super Heavy booster prior to engine installation

The first stage booster, named Super Heavy, is 70 m (230 ft) tall, 9 m (30 ft) wide, and contains thirty-three Raptor engines arranged in concentric rings. The outermost ring of 20 engines are of the "Raptor Boost" configuration with gimbal actuators removed to save weight and a modified injector with reduced throttle performance in exchange for greater thrust. At full power, all engines produce a collective 75.9 MN (17,100,000 lb_f) of thrust.

The booster's tanks can hold 3,600 t (7,900,000 lb) of propellant, consisting of 2,800 t (6,200,000 lb) of liquid oxygen and 800 t (1,800,000 lb) of liquid methane. Super Heavy uses 280 L (74 US gal) of hydraulic fluid. The final design will have a dry mass between 160 t (350,000 lb) and 200 t (440,000 lb), with the tanks weighing 80 t (180,000 lb) and the interstage 20 t (44,000 lb).

The booster is equipped with four electrically actuated grid fins, each with a mass of 3 t (6,600 lb). Adjacent pairs of grid fins are only spaced sixty degrees apart instead of being orthogonal (as is the case on Falcon 9) to provide more authority in the pitch axis. Also unlike Falcon 9, the grid fins do not retract and remain extended during ascent. The booster can be lifted through protruding hardpoints located between gridfins. During unpowered flight in a vacuum, control authority is provided by cold gas thrusters fed with residual ullage gas.

Starship spacecraft

Leeward angle of Starship SN16 spacecraft

The Starship second stage is 50 m (160 ft) tall, 9 m (30 ft) in diameter, and is fitted with 3 Raptor and 3 Raptor Vacuum engines for increased thrust in the vacuum of outer space. The vehicle's payload bay, measuring 17 m (56 ft) tall by 8 m (26 ft) in diameter, is the largest of all planned launch vehicles; its internal volume of 1,000 m³ (35,000 cu ft) is slightly larger than the International Space Station's pressurized volume. SpaceX also provides a 22 m (72 ft) tall payload bay configuration for even larger payloads.

Starship has a total propellant capacity of 1,200 t (2,600,000 lb) across main tanks and header tanks. The header tanks are better insulated due to their position and are reserved for use to flip and land the spacecraft following reentry. About 130 L (34 US gal) of hydraulic fluid is used for the spacecraft's operations. A set of reaction control thrusters, mounted on the exterior, control attitude while in space.

The spacecraft has four body flaps to control the spacecraft's orientation and help dissipate energy during atmospheric entry, composed of two forward flaps and two aft flaps. According to SpaceX, the flaps replace the need for wings or tailplane, reduces the propellant needed for landing and crucially the flaps allows landing at destinations in the Solar System where runways don't exist (for example Mars). Under the forward flaps, hardpoints are used for lifting and catching the spacecraft via mechanical arms. The flap's hinges are sealed with metal because they would be easily damaged during reentry.

Starship's heat shield, composed of thousands of hexagonal black tiles that can withstand temperatures of 1,400 °C (2,600 °F), is designed to be used many times without maintenance between flights. The tiles are made of silica and are attached with pins rather than glued, with small gaps in between to counteract heat expansion. Their hexagonal shape facilitates mass production and prevents hot plasma from causing severe damage.

Diagram of Starship's internal structure. Not shown in this diagram are the flaps: the aft flaps are placed at the bottom and the forward flaps are placed at the top portion of the spaceship.

Variants

For satellite launch, Starship will have a large cargo door which will open to release payloads and close upon reentry, instead of a more conventional jettisonable nose-cone fairing. Instead of a cleanroom, payloads are integrated directly into Starship's payload bay, which requires purging the payload bay with temperature-controlled ISO class 8 clean air. To deploy Starlink satellites, the cargo door will be replaced with a slot and dispenser rack, whose mechanism has been compared to a Pez candy dispenser.

Crewed Starship vehicles would replace the cargo bay with a pressurized crew section and would have a life support system. For long-duration missions, such as crewed flights to Mars, SpaceX describes the interior as potentially including "private cabins, large communal areas, centralized storage, solar storm shelters, and a viewing gallery". Starship's life support system is expected to recycle resources such as air and water from waste.

Starship Human Landing System (Starship HLS) is a crewed lunar lander variant of the Starship vehicle that is extensively modified for landing, operation, and takeoff from the lunar surface. It features modified landing legs, a body-mounted solar array, a set of thrusters mounted mid-body to assist with final landing and takeoff, two airlocks, and an elevator to lower crew and cargo onto the lunar surface. Starship HLS will be able to land more than 100 t (220,000 lb) of cargo on the Moon per flight.

Starship can be refueled by docking with separately launched Starship propellant tanker spacecraft in orbit. Doing so would increase the spacecraft's mass capacity and allow it to reach higher-energy targets, such as geosynchronous orbit, the Moon, and Mars. A Starship propellant depot could cache methane and oxygen on-orbit, and will be used by Starship HLS.

Mission profile

Animation of Super Heavy's integration to the launch mount, using mechanical arms

The payload is integrated onto Starship at a separate facility and then rolled out to the spaceport. After Super Heavy and Starship are stacked onto their launch mount by lifting from hardpoints, they are loaded with propellant via the quick disconnect arm and mount. Roughly four hundred truck deliveries are needed for one launch, although some commodities are provided on-site via an air separation unit. Then, the arm and mount will detach, all thirty-three engines of Super Heavy ignite, and the rocket lifts off.

A short animation of Super Heavy's landing on mechanical arms. The actual landing speed is a few times slower.

After two minutes, at an altitude of 65 km (40 mi), Super Heavy cuts off its engines and releases the inter-stage latches, causing the rocket stages to separate. The booster then flips its orientation and ignites its engines briefly. As the booster returns to the launch site via a controlled descent, it will be caught by a pair of mechanical arms. After six minutes of flight, about 20 t (44,000 lb) of propellant remain inside the booster.

Meanwhile, the Starship spacecraft accelerates to orbital velocity. Once in orbit, the spacecraft can be refueled by one or more tanker variant Starships, increasing the spacecraft's capacity. To land on bodies without an atmosphere, such as the Moon, Starship will fire its engines and thrusters to slow down. To land on bodies with an atmosphere such as Earth and Mars, Starship first slows down by entering the atmosphere via a heat shield. The spacecraft then performs a "belly-flop" maneuver, by diving back through the atmosphere body at a 60° angle to the ground, and controls its fall using the four flaps.

Shortly before landing, the Raptor engines fire, using propellant from the header tanks, causing the spacecraft to resume vertical orientation. At this stage, Raptor engines' gimbaling, throttle, and reaction control system's firing help to precisely maneuver the craft. A pseudospectral optimal control algorithm by the German Aerospace Center predicted that the landing flip would tilt up to 20° from the ground's perpendicular line, and the angle would be reduced to zero on touchdown. Future Starships are envisioned to be caught by mechanical arms, like the booster.

If Starship's rocket stages land on a pad, a mobile hydraulic lift then moves them to a transporter vehicle. If the rocket stages land on a floating platform, they will be transported by a barge to a port and finally transported by road. The recovered Super Heavy and Starship will either be positioned on the launch mount for another launch, or refurbished at a SpaceX facility. Super Heavy and Starship estmated reflight turnaround times are not clear. The previous generation Falcon 9 tightest turnaround interval as of March 2023 is 21 days.

Potential uses

Further information: List of SpaceX Starship launches

Starship's reusability is expected to reduce launch costs, expanding space access to more payloads and entities. Musk has predicted that a Starship orbital launch will eventually cost $1 million (or $10 per kilogram). Eurospace's director of research Pierre Lionnet, however, stated that Starship's launch price will likely be higher because of the rocket's development cost.

Crewed and cargo launches

Starship is also planned to launch the second generation of SpaceX's Starlink satellites, which deliver global high-speed internet. A space analyst at financial services company Morgan Stanley stated development of Starship and Starlink are intertwined, with Starship launch capacity enabling cheaper Starlink launches, and Starlink's profits financing Starship's development costs.

As of 19 August 2022, the Superbird-9 communication satellite is Starship's first and only known contract for externally made commercial satellites. The satellite weighs 3 t (6,600 lb) dry mass, planned for 2024 launch to a geostationary orbit. In the future, the spacecraft's crewed version could be used for space tourism—for example, the DearMoon project funded by Yusaku Maezawa. Another example is the third flight of the Polaris program announced by Jared Isaacman.

Farther in the future, Starship may host point-to-point flights (called "Earth to Earth" flights by SpaceX), traveling anywhere on Earth in under an hour. SpaceX president and chief operating officer Gwynne Shotwell said point-to-point travel could become cost competitive with conventional business class flights. John Logsdon, an academic on space policy and history, said point-to-point travel is unrealistic, as the craft would switch between weightlessness to 5 g of acceleration. In January 2022, SpaceX was awarded a $102 million five-year contract to develop the Rocket Cargo program.

Space exploration

Artemis 3 launch profile of a human landing on the Moon, involving Starship HLS, Starship tanker variants, and Orion spacecraft

Starship's capability could enable large space telescopes such as the Large Ultraviolet Optical Infrared Surveyor, which detects Earth-like exoplanets. Starship might also launch probes orbiting Neptune or Io, or large sample-return missions, potentially giving insight into past volcanism on the Moon and possible extraterrestrial life. The low launch cost could also allow probes to use more-common and cheaper materials, such as glass instead of beryllium for large telescope mirrors.

Opinions differ on how Starship's low launch cost will affect the cost of space science. According to Waleed Abdalati, former NASA Chief Scientist, the low launch cost will cheapen satellite replacement and enable more ambitious missions for budget-limited programs. According to Lionnet, low launch cost might not reduce the overall cost of a science mission significantly: of the Rosetta space probe and Philae lander's mission cost of $1.7 billion, the cost of launch (by the expendable Ariane 5) only made up ten percent.

Starship's lunar lander Starship HLS is critical to the NASA Artemis program for human exploration of the Moon. The lander is accompanied by Starship tankers and Starship propellant depots. The tankers transfer propellant to a depot until it is full, then the depot fuels Starship HLS. The lunar lander is thus endowed with enough thrust to achieve a lunar orbit. Then, the crews on board the Orion spacecraft are launched with the Space Launch System. Orion then docks with Starship HLS and the crews transfer into the lander. After landing and returning, the lunar crews transfer back to Orion and return to Earth.

Space colonization

Further information: SpaceX Mars program

Starship is intended to eventually be able to land crews on Mars. First, the spacecraft is launched to low Earth orbit, then is refuelled by around five tanker spacecraft before heading towards Mars. After landing on Mars, the Sabatier reaction is used to synthesise liquid methane and liquid oxygen, Starship's propellant, in a power-to-gas plant. The plant's raw resources are Martian water and carbon dioxide. On Earth, similar technologies could be used to make carbon-neutral propellant for the rocket.

SpaceX and Musk have stated their goal of colonizing Mars to ensure the long-term survival of humanity, with an ambition of sending a thousand Starship spacecraft to Mars during a Mars launch window in a very far future. Musk had maintained an interest in Mars colonization since 2001, when he joined the Mars Society and researched Mars-related space experiments before founding SpaceX in 2002. Musk has made tentative estimates of Starship's Mars landing; in March 2022, he gave a date of 2029 for the first crewed Mars landing. SpaceX has not published technical plans about Starship's life support systems, radiation protection, or in-orbit refueling.

Facilities

See also: SpaceX facilities

Testing and manufacturing

A bay at Starbase build site, hosting construction of prototypes

Starbase consists of a manufacturing facility and launch site, and is located at Boca Chica, Texas. Both facilities operate twenty-four hours a day. and a maximum of 450 full-time employees may be onsite. The site is planned to consist of two launch sites, one payload processing facility, one seven-acre solar farm, and other facilities. As of April 2022, the expansion plan's permit has been withdrawn by the United States Army Corps of Engineers, citing lack of information provided. The company leases Starbase's land for the STARGATE research facility, owned by the University of Texas Rio Grande Valley, and uses part of it for Starship development.

At McGregor, Texas, the Rocket Development facility tests all Raptor engines. The facility has two main test stands: one horizontal stand for both engine types and one vertical stand for sea level-optimized rocket engines. Other test stands are used for checking Starship's reaction control thrusters and Falcon's Merlin engines. The McGregor facility previously hosted test flights of landable first stages—Grasshopper and F9R Dev1. In the future, a nearby factory, which as of September 2021 was under construction, will make the new generation of sea-level Raptors while SpaceX's headquarters in California will continue building the Raptor Vacuum and test new designs.

At Florida, a facility at Cocoa purifies silica for Starship heat-shield tiles, producing a slurry that is then shipped to a facility at Cape Canaveral. In the past, workers there constructed the Starship Mk2 prototype in competition with Starbase's crews. The Kennedy Space Center, also in Florida, is planned to host other Starship facilities, such as Starship launch sites at Launch Complex 39A, the planned Launch Complex 49, and a production facility at Roberts Road. This production facility is being expanded from "Hangar X", the Falcon rocket boosters' storage and maintenance facility, and will include a 30,000 m² (320,000 sq ft) building, loading dock, and a place for constructing integration tower sections.

Launch sites

A launch site at Starbase, showing a tank farm and an integration tower in construction

Starbase is planned to host two launch sites, named Pad A and B. A launch site at Starbase has large facilities, such as a tank farm, launch pad, and an integration tower. Smaller facilities are present at the launch site: Tanks surrounding the area contain methane, oxygen, nitrogen, helium, hydraulic fluid, etc.; subcoolers near the tank farm cool propellant using liquid nitrogen; and various pipes are installed at large facilities. Each tank farm consists of eight tanks, enough for one orbital launch. The launch pad has a water sound suppression system, twenty clamps that hold down the booster, and a quick disconnect mount that provides the rocket with liquid propellant and electricity.

The integration tower or launch tower consists of steel truss sections, a lightning rod on top, and a pair of mechanical arms that can lift, catch and recover the booster. The decision was made for enabling rapid reflights, as well as reducing the rocket's mass and part count. The mechanical arms are attached onto a carriage and controlled by a pulley at the top of the tower. The pulley is linked to a winch and spool at the base of the tower, using a cable. Using the winch, the carriage and mechanical arms can move vertically, with support from bearings attached at the sides of the carriage. A linear hydraulic actuator is used to move the arms horizontally. Tracks are mounted on top of arms, which are used to position the booster or spacecraft precisely. The tower is mounted with a quick disconnect arm that can extend to and contract from the booster; its functions are similar to the quick disconnect mount.

Starship launch tower (left) in construction at Kennedy Space Center's LC-39A

Since 2021, the company is constructing a Starship launch pad in Cape Canaveral, Florida in Kennedy Space Center's Launch Complex 39A, which is currently used to launch Crew Dragon capsules to the International Space Station. SpaceX plans to make a separate pad at 39A's north, named Launch Complex 49. Because of Launch Complex 39A's Crew Dragon launches, the company is studying how to strengthen the pad against the possibility of a Starship explosion and proposed to retrofit Cape Canaveral Space Launch Complex 40 instead. The towers and mechanical arms at the Florida launch sites should be similar to the one at Starbase, with improvements.

Phobos and Deimos are the names of two Starship offshore launch platforms, both in renovation as of March 2022. Before being purchased from Valaris plc in June 2020, they were nearly identical oil platforms named Valaris 8501 and Valaris 8500. Their main decks are 78 m (260 ft) long by 73 m (240 ft) wide; their four columns are 15 m (49 ft) long and 14 m (46 ft) wide; and their helicopter decks are 22 m (72 ft) in diameter. In February 2022, Musk stated Phobos and Deimos are not yet SpaceX's focus, but that in the far future, most Starship launches would start from offshore platforms.

Community reception

Starship SN15 and SN16 juxtaposed with a local tiki bar

Outside the space community, reception to Starship's development among nearby locales has been mixed, especially from cities close to the Starbase spaceport. Proponents of SpaceX's arrival said the company would provide money, education, and job opportunities to the country's poorest areas. Fewer than one-fifth of those twenty-five or older in the Rio Grande Valley have a bachelor's degree, in comparison to the national average of one-third. The local government has stated that the company boosted the local economy by hiring local residents and investing, aiding the three-tenths of the population who live in poverty.

Opponents say the company encourages Brownsville's gentrification, with an ever-increasing property valuation. Even though Starbase had been originally planned to launch Falcon rockets when the original environmental assessment was completed in 2014, the site in 2019 was subsequently used to develop Starship, ultimately requiring a revised environmental assessment. Some of the tests have ended in large explosions, causing major disruption to residents and wildlife reserves. The disruption to residents is compounded by SpaceX's frequent closures of the road to the beach for vehicle testing. Some residents have moved away or requested financial reparations from the company.

According to an analysis by SpaceFlight Now, the combined Starship and Super Heavy together stands at a towering 394 feet tall (120 meters) compared to the Saturn 5 rocket at 363 feet (111 meters), which brought astronauts to earth and lunar orbit in the early 1970s. SpaceX's 33 Raptor engines are generating more than 16 million pounds of thrust, roughly twice that of the Saturn 5, but the former disintegrated soon after launch on 20 April 2023, causing environmental concerns and personal injury in Texas. In comparison, Saturn 5 rockets that originated from a design by Werner von Braun never failed and were considered a safe space launch vehicle. As the Pentagon is increasingly relying on large rockets designed by billionaires, the Russian-built Yenisei super-heavy rocket is currently a favored approach for space exploration. A Chinese vehicle with similar capabilities is also believed to be in the works. According to informed sources, "the Pentagon relies on executable and enforceable contracts with industry", yet a large rocket with 33 Raptor engines is statistically more likely to fail than an advanced Yenisei super-heavy rocket with two four-chamber RD-171MV engines on two boosters.

External links

• Official website
• Programmatic Environmental Assessment by the Federal Aviation Administration
• Starship of SpaceX on eoPortal directory, administered by the European Space Agency
• Tim Dodd's Starship interviews with Elon Musk on YouTube:
  • A conversation with Elon Musk about Starship, 2019
  • Starbase and Starship tour, 2021: part 1, part 2, and part 3
  • Launch tower and Raptor engine tour, 2022: overview, launch infrastructure, Raptor engine