SpaceX Starship

Starship

Starship launch vehicle assembled and stacked at Starbase
Function	sub-orbital spaceflight orbital spaceflight interplanetary spaceflight
Manufacturer	SpaceX
Country of origin	United States
Size
Height	121.3 m 398 ft
Diameter	9 m 29.5 ft
Mass	5,000 t 11,000,000 lb
Launch history
Launch sites	Starbase Launch Site Kennedy Space Center Launch Complex 39A
Capacity with refueling Payload to low Earth orbit Mass 150 t 330,000 lb Volume 1,000 m³ 35,000 ft³ Payload to Moon Mass 100 t 220,000 lb Volume 1,000 m³ 35,000 ft³ Payload to Mars Mass 100 t 220,000 lb Volume 1,000 m³ 35,000 ft³
Stage information 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 fully reusable, super heavy-lift launch vehicle that is currently being developed and manufactured by American aerospace manufacturer SpaceX. It is the tallest and most powerful rocket ever built. The rocket consists of the Super Heavy booster stage and the Starship spacecraft on top, and is mainly constructed out of stainless steel. Both stages are fueled with liquid oxygen and methane, and are propelled by variants of Raptor engines. Both stages are designed for rapid reuse after a vertical landing. With a single launch, the expected payload to low Earth orbit is at least 100 t (220,000 lb). The planned Starship tanker variant can be used to refuel the main spacecraft in orbit, leading to the same payload for flights to the Moon and Mars.

SpaceX outlined such a rocket as early as 2005; its design and name were frequently changed. In July 2019, Starhopper, a prototype vehicle with extended fins, was able to hover. In May 2021, Starship SN15 flew to 10 km (6 mi) and landed after four failed attempts with earlier prototypes. As of June 2022, the first Starship rocket is planned to launch in 2022 pending regulatory approval. The rocket's development is iterative and incremental with testing and manufacturing of prototypes. Critics, however, have noted its potential to damage the natural and social environment around the launch sites.

SpaceX plans to construct launch sites at Starbase in Texas and Kennedy Space Center in Florida, and to build two offshore launch platforms. In the near-term, Starship may deploy satellites and space probes, serve space tourists, and explore the Moon via the Artemis program. Further into the future, the rocket may travel between locations on Earth and aid SpaceX's ambition of colonizing Mars. Such level of operation is only possible with reduced launch cost.

Background

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

SpaceX illustration of the 2016 Interplanetary Transport System

SpaceX illustration of the 2018 Big Falcon Rocket in flight

In November 2005, in the United States, SpaceX CEO Elon Musk first referenced a rocket concept known as Big Falcon Rocket (BFR), which matched some capabilities of the current Starship design. The rocket was to be equipped with a larger version of the Merlin engine known as Merlin 2. The concept had a lifting capacity of 100 t (220,000 lb) to low Earth orbit and was unable to relaunch. The announcement of this concept roughly coincided with the company's first and unsuccessful launch attempt, carrying FalconSAT-2 on the small Falcon 1 rocket.

In 2011, SpaceX outlined a reduced-cost Mars mission using the Red Dragon capsule, a modified version of the Dragon 1 capsule. This plan was abandoned around 2017, when the propulsive landing technology for the Dragon capsule was deemed unnecessary. In 2012, the company revisited the plan in the form of the Mars Colonial Transporter concept, whose design was to be powered by methane-fueled Raptor engines and would have a capacity of 100 people or 100 t (220,000 lb) of cargo to Mars. In September 2014, SpaceX broke ground on the Starbase facility for developing Falcon 9 and Falcon Heavy. In December 2015, the company's reusable launch system development program achieved the first booster landing at Falcon 9 flight 20.

In September 2016, a day before the 67th International Astronautical Congress, the Raptor engine was fired for the first time. At the event, Musk announced SpaceX was developing a new rocket, the Interplanetary Transport System, which would have a launch capacity of 300 t (660,000 lb) to low Earth orbit and both stages would be reusable. This concept presented the possibility of a "space tanker"; a launch vehicle capable of carrying extra fuel to orbit, transferring fuel to another spacecraft in orbit, landing, and repeating the process. The rocket's tanks were to be made from carbon composite, and would store liquid methane and liquid oxygen. The booster stage was to be equipped with forty-two Raptor engines while the spacecraft would have been equipped with nine. The concept, especially the technological feats required to make such a system possible and the funds needed, garnered a great deal of skepticism.

In September 2017, at the 68th Annual International Astronautical Congress, Musk announced the BFR, a revision to the Interplanetary Transport System's design. The rocket was said to be able to put 150 t (330,000 lb) to low Earth orbit and be reusable. The booster's engine count was reduced to thirty-one, and the rocket's body was smaller. Unlike its conceptual predecessor, the potential applications for the BFR were far more varied: sending satellites to orbit, resupplying the International Space Station, landing on the Moon, and traveling between locations on Earth. Nevertheless, its ultimate purpose was still to ferry crew to Mars. A rocket production facility at the Port of Los Angeles had received approval by City Council, but the plan was cancelled around May 2020.

In September 2018, Japanese billionaire Yusaku Maezawa announced the sponsored DearMoon project, which was led by Maezawa. With six to eight other artists, the crew would fly a free-return trajectory around the Moon on a BFR spacecraft, creating artworks throughout the mission. Musk commented the project gave considerable funding to the rocket's development. After Maezawa's announcement, Musk showed the rocket's new addition of flaps; two at the top and three at the bottom, which could be adjusted to control the spacecraft's descent, and the bottom flaps could have also be used as landing legs. That November, the rocket booster was first termed Super Heavy and the spacecraft was named Starship.

Development

Main articles: SpaceX Starship development and List of SpaceX Starship launches

Starship's development is iterative and incremental, and is mostly funded by SpaceX. The company has now built and tested nine full-scale models of the Starship upper stage and scrapped others before completion. Tests conducted range from proof pressure tests and static fires to full-flight tests with attempted recovery. Due to the company's openness to space news media, Starship rocket tests have received significant coverage.

Reception to Starship development among local communities has been mixed, especially from cities near the Starbase spaceport. Proponents of SpaceX's arrival said the company would provide money, education, and job opportunities. Starbase was constructed relatively close to the Brownsville–Harlingen–San Benito metropolitan area, which was near the bottom of 2010's list of United States metropolitan areas by per capita income. Local governments have stated SpaceX boosted the local economy by hiring local residents and increasing investment.

Opponents of the plan said the company encourages Brownsville's gentrification and over-reliance on STEM fields. They also highlighted the spaceport's dishonest planning; Starbase was originally planned to launch Falcon rockets but the site was exclusively used to test Starships without being reassessed for environmental damage. Some of the failed tests have resulted in large explosions, which scattered debris around Boca Chica Beach at Cameron County, causing major disruption to nearby wildlife reserves. SpaceX has also been criticized for interfering with Boca Chica residents' daily lives because nearby beaches and roads are frequently closed. Because of this, some residents have moved away or demanded financial reparations from the company.

Low-altitude flights

Starhopper while under construction

A crane lifting Starship SN5

The first prototype to fly using a Raptor engine was the Starhopper. The vehicle had three non-retractable legs and was shorter than the final spacecraft design. The craft performed two tethered hops in early April 2019 and two months later, it hopped without a tether to 20–30 m (70–100 ft). In August 2019, the vehicle hopped to 150 m (500 ft) and traveled to the landing pad 100 m (300 ft) away. As of August 2021, the vehicle has been retired and repurposed; it is now a mounting point for radio communication, weather monitoring, ground station equipment, and a water tank.

SpaceX subsequently constructed the "Starship Mk1" and "Starship Mk2" upper-stage prototypes, which were located at Starbase and the SpaceX facility in Cocoa, Florida, respectively. In late September 2019, Musk presented more details about the lower-stage booster, the upper stage's method of controlling its descent, its heat shield, orbital refueling capacity, and potential destinations outside Mars. The spacecraft design was once again changed; the number of aft flaps was reduced from three to two. Musk also said Starship's material was changed from carbon composites to stainless steel, citing lower cost, higher melting point, strength at cryogenic temperatures, and ease of manufacturing. After the presentation, Mk1 was destroyed two months later during a pressure stress test and Mk2 did not fly because the Florida facility was deconstructed throughout 2020.

In January 2020, SpaceX bought two drilling rigs for $3.5 million from Valaris plc, each during Valaris's bankruptcy proceedings; it planned to repurpose the rigs as offshore spaceports. SpaceX began naming its new Starship upper-stage prototypes with the prefix "SN". No prototypes between SN1 and SN4 flew; SN1 and SN3 collapsed during a proof-pressure test and SN4 exploded after its fifth engine firing. During the interval, the company accelerated the construction of infrastructure at Starbase, which used large tents, stations, and repurposed intermodal containers. When linked together, these facilities functioned as a production line, hastening rocket construction.

In June 2020, SpaceX began construction of a launch pad for orbit-capable Starship rockets. Around that time, Starship SN5 was built; the lack of flaps or nose cone gave it a cylindrical shape. The test vehicle consisted of one Raptor engine, full-size propellant tanks, and a mass on top. SN5 performed a 150 m (500 ft)-high flight on 5 August 2020, successfully landing on a nearby pad. On 3 September, the similar-looking Starship SN6 successfully repeated the hop. A week later, SpaceX stress-tested a fuel tank, designated SN7.1, which was constructed from SAE 304L stainless steel grade rather than SAE 301 steel grade of earlier tanks. In the same September, the company first fired its Raptor Vacuum engine.

High-altitude flights

Starship SN9 on a mount with its flaps closed

Animation depicting a successful test flight following the flight profile of SN8 to SN15.

SN8 was the first complete Starship prototype and underwent four static fire tests between October and November 2020. The third test ingested fragments of pad material into its engine internals, causing a premature shutdown. The fourth static fire was successful and on 9 December 2020, SN8 flew, reaching an altitude of 12.5 km (7.8 mi). A few seconds before touchdown, however, a propellant flow issue caused the prototype to lose thrust and impact the pad. The test provoked condemnation from Federal Aviation Administration (FAA) Associate Administrator Wayne Monteith because SpaceX had ignored FAA warnings weather conditions at the time could have worsened damage from a possible in-flight explosion to nearby homes. On 2 February 2021, Starship SN9 launched on an identical flight path and also crashed on landing.

In March 2021, the company sent a public construction plan that had two sub-orbital launch pads, two orbital launch pads, two landing pads, two test stands, and a large tank farm that stores propellant, to the United States Army Corps of Engineers. The company proposed developing the surrounding village Boca Chica into a company town named Starbase, raising concerns about SpaceX's authority, power, and potential abuse for eviction. On 3 March 2021, after an initially aborted launch, Starship SN10 launched on the same flight path as its two predecessors. The vehicle then landed hard and crushed its landing legs. Minutes later, it exploded due to a propellant tank rupture.

After approval from the FAA, on 30 March 2021, Starship SN11 flew into thick fog along the same flight path. The vehicle exploded during descent, scattering debris up to 8 km (5 mi) away. In early April 2021, the orbital launch pad's fuel storage tanks began to be mounted. Around the same time, despite earlier misgivings about its complexity, NASA selected Starship HLS as the crewed lunar lander. Blue Origin disputed the decision and began a six-month-long legal battle titled Blue Origin v. United States & Space Exploration Technologies Corp. Starship models SN12, SN13, and SN14 were scrapped before completion, and Starship SN15 was selected to fly instead. On 5 May 2021, SN15 launched, completed the same maneuvers as older prototypes, and landed softly, completing the first successful high-altitude test.

Planned orbital launches

Examination of Starship SN20's heat shield

Engine firing of Starship SN20 near Super Heavy boosters and launch tower

In July 2021, Super Heavy BN3 conducted its first partial static firing, lighting three engines. Super Heavy BN4 was the first design to mate with a Starship upper stage while Starship SN20 was the first to include a body-tall heat shield, mostly made of black, hexagonal, heat tiles. A month later, using cranes, Starship SN20 was stacked atop Super Heavy BN4 for the first time. In October 2021, the catching mechanical arms were installed onto the launch tower, forming the booster recovery system, and the last tank's thermal insulation cover was installed, marking the completion of the first tank farm. On 26 November 2021, a day after Thanksgiving in the United States, Musk sent an internal email to all SpaceX employees saying the Raptor engine's production line was not sufficiently mature, creating a risk of bankruptcy for the company.

Two weeks later, north of Launch Complex 39B, NASA and SpaceX announced their plans to create Launch Complex 49, which will launch Starship rockets from Kennedy Space Center. In February 2022, after stacking Starship SN20 on top of Super Heavy BN4 using mechanical arms for the first time, Elon Musk gave a presentation on Starship development at Starbase. He clarified much of the information provided in the past, and gave updates on Starship HLS, Raptor engine production, the environmental assessment of Starbase, and the reopening of the Florida facility. The next month, SpaceX president Gwynne Shotwell said the company would stop production of new Crew Dragon capsules and would focus on crewed Starship missions.

As of 31 May 2022, the FAA intends to release its final Programmatic Environmental Assessment (PEA) on June 13th. The company explained the planned trajectory in a report sent to the Federal Communications Commission (FCC). The rocket is planned to launch from Starbase, after which the Super Heavy booster will separate and perform a soft water landing around 30 km (20 mi) from the Texas shoreline. The spacecraft will continue flying with its ground track passing through the Straits of Florida and then softly land in the Pacific Ocean around 100 km (60 mi) northwest of Kauai in the Hawaiian Islands. The spaceflight will last ninety minutes.

Design

Starship is designed to be a fully reusable orbital rocket, aiming to drastically reduce launch costs. One launch may deliver more than 100 t (220,000 lb) to low Earth orbit, which would formally classify the rocket as a super heavy-lift launch vehicle. When stacked and fueled, Starship may be about 5,000 t (11,000,000 lb) by mass, 9 m (30 ft) wide, and 120 m (390 ft) high, taller than the Saturn V by 9 m (30 ft). 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. These rocket stages' reusability and stainless-steel construction has influenced other rockets such as the Terran R and Project Jarvis.

According to Eric Berger from Ars Technica, manufacturing of the Starship rocket starts with rolls of SAE 304L-grade stainless steel. They are then 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. To make the outer layer of the Starship spacecraft, seventeen of these cylinders and nose cones are stacked and welded along their edges. Inside the body are domes separating liquid methane and oxygen tanks at high pressure that are made by robots and welded at the rate of ten minutes per seam, and are later inspected with an X-ray machine.

Raptor engine

Main article: SpaceX Raptor

Sea level-optimized Raptor engine

First test firing of the sea-level Raptor engine, with methane combusted to produce a purple-orange flame

Raptor is a family of SpaceX-manufactured rocket engines used in Starship. In a full-flow staged combustion cycle, Raptor burns liquid oxygen and methane. The family uses a new alloy and can obtain 300 bar (4,400 psi) inside the main combustion chamber. These engines can fire many times; their nozzles are cooled by surrounding, running propellant called regenerative cooling. In the future, the engine family may be mass-produced and may cost about $230,000 per engine and $100 per kilonewton.

The Raptor family is the only full-flow staged combustion cycle engine currently in production. In the past, the Soviet Union and the United States tried to construct such an engine, but both products have never been put in use. A general full-flow staged combustion cycle engine has two preburners connected to their matching turbopumps. One of the preburners is fed with an oxygen-rich mixture and the other is fed with a propellant-rich mixture, combusting a small amount to spin the matching turbines. The cycle then feeds all gaseous propellant mixture into the combustion chamber, unlike other engine cycles that waste some propellant. This increases the engine's chamber pressure, making more thrust and being more efficient overall.

Methane was chosen for the Raptor engines because it may be cheaper, does not accumulate soot, and could be produced on Mars via the Sabatier reaction. The engines run at an oxygen-to-methane mass ratio of 3.6 : 1; combusting a stoichiometric mixture of 4 : 1 would overheat and damage them. The exhaust contains carbon dioxide, water, and trace amounts of carbon monoxide and nitric oxide. The plume stretches about 65 m (213 ft) at full power, and is about 15 m (49 ft) longer than the Starship spacecraft. When clustered inside a rocket stage, the inner engines' plumes do not immediately interact with air so the cluster's plume may be much longer.

SpaceX builds other variants of Raptor; it specifies the Raptor engine has a throat-area-to-exit-area ratio of 1:34. Another variant is the Raptor Vacuum, which is designed to be fired in space, and is equipped with a nozzle extension made from brazed steel tubes, increasing the throat-area-to-exit-area ratio to 1:90 and specific impulse or fuel efficiency to 380 seconds. The Raptor 2 is the next generation in the family; the engine may produce 2.3 MN (520,000 lb_f) of thrust and its specific impulse is reduced by three seconds. The new generation of Raptor has a simpler design than the earlier version. In the long term, SpaceX plans to make three variants of Raptor; sea-level-optimized engine with gimbaled thrust, sea-level-optimized engine without gimbaled thrust, and vacuum-optimized engine without gimbaled thrust.

Super Heavy booster

Super Heavy is the rocket's booster or first stage, and forms the lowest part of the rocket. The booster measures 70 m (230 ft) tall, and houses up to thirty-three sea level-optimized Raptor engines. The engine cluster may be more than twice as powerful as the Saturn V, the rocket that was used for the NASA Apollo program of the 1960s and 1970s. The Super Heavy's 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. Without propellant, Super Heavy's dry mass is estimated to be between 160 t (350,000 lb) and 200 t (440,000 lb); of which, the tanks weigh 80 t (180,000 lb), the interstage between the booster and spacecraft weighs 20 t (44,000 lb), and all the engines and mounts weigh 52 t (115,000 lb).

The booster is equipped with four grid fins, each of which has a mass of 3 t (6,600 lb). The grid fins are unevenly spaced to allow the craft to obtain more pitch control and can only rotate in the roll axis. The fins may control the booster's descent and work as a mounting point for a touchdown into the tower's mechanical arms. Though catching Super Heavy requires great precision, this may reduce the turnaround time after landing and enable frequent launches. To control the booster's orientation, Super Heavy may fire cold gas thrusters that are fed with propellant that evaporates inside the tanks. While Super Heavy and Starship are attached in space, the booster can move its engines and separate from the spacecraft.

Starship spacecraft

Leeward angle of Starship SN16 spacecraft

Starship SN8 spacecraft's test flight that launched vertically. The spacecraft would also land in this orientation, after the belly-flop maneuver.

The Starship spacecraft is being designed to be used both as a long-duration spacecraft on some missions and as the second stage of the two-stage-to-orbit launch vehicle on every launch. The spacecraft is 50 m (160 ft) tall and has a dry mass of less than 100 t (220,000 lb). By refueling the Starship spacecraft in orbit using tanker spacecraft, Starship may transport payloads and astronauts to high Earth orbits, the Moon, Mars, and other destinations in the Solar System. Starship has two main tanks and two header tanks, with a total propellant capacity of 1,200 t (2,600,000 lb). The main tanks and header tanks of the Starship spacecraft hold either liquid oxygen or liquid methane; the header tank's capacity is reserved to flip and land the spacecraft following reentry. Starship's payload volume may be as large as 1,000 m³ (35,000 cu ft), far larger than any other spacecraft in the previous seven decades of spaceflight.

At the bottom of the Starship spacecraft are six Raptor engines, three of which are designed for satisfactory operation in the lower atmosphere and will also support propulsive landings, while the other three Raptor Vacuum engines are optimized to operate in the vacuum of space. The spacecraft has four body flaps to control the spacecraft's falling velocity and orientation; two forward flaps are mounted near the nose cone and two aft flaps are mounted near the bottom. The hinges that mount them are sealed with metal because they are easily damaged during reentry. Starship's heat shield, which is composed of thousands of hexagonal tiles— each mounted and spaced to counteract expansion due to heat— is designed to be used multiple times, ultimately with no maintenance between flights. The tiles' hexagonal shape is designed to help prevent hot plasma from causing damage, allowing it to withstand temperatures of 1,400 °C (2,600 °F). The spacecraft nose cone, as of August 2021, is made from two rows of stretch-formed steel.

Variants

SpaceX has produced an initial cargo Starship spacecraft variant that is specialized for deployment of Starlink V2.0 satellites. This variant is likely to be used for the initial orbital launches. The satellites are loaded through a short but wide door slot into a stacking system within the Starship that has been likened to a "Pez dispenser". Upon reaching orbit the satellites are to be deployed through the door slot.

A more generic cargo variant may feature a large door replacing conventional payload fairings, which can launch, store, capture, and return payloads. The payload door would be closed during launch, opened to release its payload once in orbit, and closed again during reentry. It may be possible to mount the payload on the inside of the payload bay's sidewalls using trunnions, more suitable for payloads on ride-share missions. Payloads may be integrated into a vertical rocket inside temperature-controlled, ISO class 8 clean air.

The crew variant can be adapted for missions to the Moon, Mars, point-to-point flights, and other destinations. Each spacecraft can carry one hundred people, with "private cabins, large communal areas, centralized storage, solar storm shelters, and a viewing gallery". Starship's life-support system is expected to be closed, where resources are constantly recycled. Other than that, little information about it is provided to the public.

The tanker variant can be used to refuel another spacecraft in orbit. According to Musk, up to seven launches of the tanker are needed to send a spacecraft to the Moon. The concept was detailed by Musk in September 2019, by docking the ends of both spacecraft to each other. They then accelerate slightly toward the tanker using control thrusters, settling propellant to the fueled Starship. In October 2020, NASA awarded SpaceX US$53.2 million to conduct a large-scale flight demonstration, transferring 10 t (22,000 lb) of propellant between the tanks of two Starship spacecraft.

Starship HLS is a crewed lunar lander variant of the Starship spacecraft for NASA's Artemis program. The lunar lander may have windows and airlocks near the top, along with an elevator and a set of thrusters to land on the Moon's surface. The lunar lander may be able to carry a large amount of payload between outer space and the Moon. On an Artemis mission, it may launch ahead of the crew by up to a hundred days, accompanied with launches of refueling Starship tankers. Another variant of the lunar lander may be used for the Commercial Lunar Payload Services program, where scientific, exploration, and commercial payloads are tasked with being sent to the Moon.

Mission profile

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

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

An example launch complex at Starbase consists of a launch pad, a launch tower, and a tank farm. The launch pad has a water sound suppression system and twenty clamps that hold down the booster until launch. The launch tower consists of steel truss sections, a lightning rod on top, and a pair of mechanical arms that may catch and recover the booster. Each tank farm consists of eight tanks; three for liquid oxygen, two for liquid methane, two for liquid nitrogen, and one for water. Other tanks surrounding the area contain other commodities, such as methane, oxygen, nitrogen, helium, and hydraulic fluid.

Before launch, Super Heavy and Starship are stacked onto a launch mount and loaded with propellant. Then, all thirty-three engines of Super Heavy fire and the rocket lifts off. After two minutes, the stages separate via the conservation of angular momentum. The booster flips its orientation, activates its central engine cluster, and return to the launch site using a controlled descent and a landing burn. A pair of mechanical arms catches the booster and place it onto the mount. After six minutes in flight, about 20 t (44,000 lb) of propellant remains inside the booster.

Meanwhile, the Starship spacecraft accelerates to orbital velocity and circularizes its orbit, where the spacecraft may be refueled by docking it with the Starship tanker variants. Both vehicles then accelerate slightly toward the tanker using control thrusters, settling propellant into the fueled Starship, which then fires its engines and coasts to its destination.

For landing on bodies without an atmosphere such as the Moon, Starship turns on its engines and thrusters to slow down and land. For bodies with an atmosphere such as Mars, Starship slows down by entering the atmosphere and is protected by a heat shield. After atmospheric entry, Starship performs a belly flop maneuver that a white paper defines as the control of its surface area, leading to the control of aerodynamic drag and terminal velocity. Tim Dodd, American space and science communicator, analyzed the maneuver and highlighted its large propellant saving compared to the Falcon 9 first stage's landing.

During landing, both liquid methane and oxygen header tanks are used to feed the Raptor engines. A pseudospectral optimal control algorithm predicted the landing flip may cause Starship to overshoot the landing point by 100 m (300 ft), and also predicted the spacecraft would intentionally tilt 20° further from the ground's normal line and then reduce to zero on touchdown. The spacecraft's landing may cause noise levels of than 60 dB(A) at Brownsville, similar to Super Heavy's landing noise level but less than that of a liftoff.

Applications

Starship would replace all functions of SpaceX's Falcon 9 and Falcon Heavy rockets, launching satellites and crew to Earth orbit and to celestial bodies. As a heavy-lift vehicle, Starship is best suited to flying large satellites and multi-payload missions. It is hoped its reusability will reduce launch costs, expanding space access to more payloads and entities. Musk predicts Starship will cost less than $10 million for an orbital launch but multiple experts claim otherwise, citing the rocket's multi-billion-dollar development cost and its current lack of external demand. Pierre Lionnet, director of research at Eurospace, said launch cost may not play a key role in certain science payloads.

If SpaceX's vision is fully realized, Starship will be able to launch up to three times per day, which would cause large greenhouse gas emissions; one space physicist roughly calculated one Starship launch produces the equivalent of continuously flying an airplane for three years. A substantial carbon footprint may result from propellant production, transportation, and storage. Analysis of rocket emissions, however, is complicated and more research may be needed.

Commercial

Starship is intended to launch the next generation of SpaceX's Starlink communication satellites. A space analyst at financial services company Morgan Stanley said development of Starship and Starlink are intertwined with each other because improvements in launch capacity and cost reduction aid Starlink satellite launches, and Starlink profits can be fed into Starship development. A single orbital launch of Starship could place up to 400 Starlink satellites into orbit; for comparison, Falcon 9 flights in 2019 and 2020 have launched a maximum of 60 satellites.

One potential use for Starship is space tourism; a example is the DearMoon project announced by Japanese entrepreneur Yusaku Maezawa, which consists of a flight around the Moon aboard Starship with a crew consisting of Maezawa and eight others. Another example is the third flight of the Polaris program announced by Jared Issacman, Mission Commander of the Inspiration4 mission, which aimed to raise funds for St. Jude Children's Research Hospital.

The spacecraft may host point-to-point flights – coined "Earth to Earth" by SpaceX – by traveling between spaceports on Earth. For example, a flight between New York City and Shanghai is estimated to take about 39 minutes. SpaceX president and chief operating officer Gwynne Shotwell predicted 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 would have a high acceleration, making it impractical for civilians.

Space exploration

Starship juxtaposed with the Moon, one of the spacecraft's potential future destinations

Starship may be capable of launching large space telescopes such as the Habitable Exoplanet Imaging Mission that can directly image planets outside the Solar System. Waleed Abdalati, a former NASA Chief Scientist, said the rocket may enable the recovery of defunct artificial objects in space.

Starship may be immensely useful beyond Earth orbit. Some planetary science researchers are beginning to incorporate Starship into their project plans, citing its low cost and high launch capacity. Starship may enable direct Hohmann transfers to other planets, lowering transit times. The probes it sends may be larger and more complex than those launched by conventional means, providing benefits for scientific investigation.

According to NASA's Ames Research Center, because Starship may have a large payload capacity, it may enable the transportation of heavy machinery such as drilling rigs to destinations in space. The mission may enable more comprehensive research of planetary interiors and underground resources, which earlier rockets would not be able to do at a reasonable cost. Starship may enable large experiments and sample-return missions to the Moon and Mars that could be integrated into SpaceX's test landings of the spacecraft. Such a mission may investigate problems in astronomy, such as past volcanism on the Moon and the possible existence of extraterrestrial life.

Military

Although the United States military has not publicly announced any satellite launch contracts for Starship, the Falcon 9 and Falcon Heavy have been used to launch payloads for the U.S. Space Force and the United States Department of Defense. Due to the increasing size and complexity of military satellites, it is likely Starship will be used for future missions. As of January 2022, SpaceX was awarded a $102 million, five-year contract to develop the Rocket Cargo program to examine the modification of Starship rockets to carry about 90 tonnes (200,000 lb) of military cargo to anywhere in the world within an hour for tactical and humanitarian purposes.

Space colonization

Further information: SpaceX Mars program

SpaceX has said its goal is to colonize Mars to ensure the long-term survival of the human species. Therefore, Starship is aimed to be a fully operational, long-duration Mars spacecraft and able to send back crew to Earth. Musk has been pursuing the goal since 2001 with the Mars Oasis program, in which a rocket would launch a greenhouse to Mars. The project's purpose was to stimulate the space market and increase NASA's budget. The final goal of the program is to send a million people to Mars by 2050 with 1,000 Starships sent during a Mars launch window. On Mars, the Sabatier reaction may be used to create liquid methane and liquid oxygen in a power-to-gas plant, fueling return missions. On Earth, carbon-neutral propellant for Starship can be made if atmospheric carbon dioxide and renewable energy are used.

Musk said SpaceX may land the first humans on Mars before 2026 but this goal is considered optimistic. Greg Autry, a space policy expert, said even with aid from NASA, such a mission might not happen before 2029. According to a NASA Office of Inspector General document, SpaceX has rated Starship HLS's propulsion, communications, and life-support system as technology readiness level 6 and 7 respectively, meaning the technology has been demonstrated with prototypes. Super Heavy booster and propellant-fueling function were rated technology readiness levels 4 and 5 respectively, meaning the technology has reached "validated" status. SpaceX has not detailed plans for life-support systems, radiation protection, and in situ resource utilization, technologies which are essential for space colonization.

Facilities

A bay at Starbase build site, hosting construction of prototypes

A launch complex at Starbase, showing a tank farm and a launch tower

The SpaceX Starbase consists of a manufacturing facility and launch site, and is located at Boca Chica, Texas. Both facilities operate for twenty-four hours a day, and a maximum of 450 full-time employees may be onsite. The site hosted the STARGATE facility of the University of Texas Rio Grande Valley. SpaceX uses part of the facility for Starship development, while university uses most of it for the study and research of space technologies. The site is planned to consist of two launch complexes, two payload processing facilities, a desalination plant, a natural-gas-fired power plant, a natural-gas purifier, a liquefier, and a solar power plant. In March 2022, one of Starship SN8's flaps was on public display at Brownsville/South Padre Island International Airport.

Phobos and Deimos are the names of two Starship offshore launch platforms, both of which were 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 in SpaceX's focus but he predicted most launches would start from offshore platforms in the far future.

As of December 2021, Kennedy Space Center is considering to have Starship launch pads at Launch Complexes 39A and 49. Launch Complex 39A had hosted Space Shuttle launches and Launch Complex 49 has been in the construction plan since 2014. If NASA approves these spaceports, SpaceX will build them north of Launch Complex 39B and need room inside the Vehicle Assembly Building, which has four high bays—three of which are reserved for the Space Launch System—and NASA can lease the remaining bay for the indoor preparation of Starship.

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 Merlin engines. In the past, the McGregor facility 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.

As of February 2022, a facility at Cocoa, Florida, processes raw materials for heat-shield tiles. In the past, workers at this facility constructed the Starship Mk2 prototype in competition with Starbase's crews. The facility is planned to expand to have Falcon rocket booster hangars and a Starship launch complex. According to Musk, if Starbase does not pass its environmental review, the Cocoa facility will become a primary launch site.

External links

• Official website