Space Exploration Technologies Corp., doing business as SpaceX, is a private American aerospace manufacturer and space transport services company headquartered in Hawthorne, California. It was founded in 2002 by entrepreneur Elon Musk with the goal of reducing space transportation costs and enabling the colonization of Mars.[8] SpaceX has since developed the Falcon launch vehicle family and the Dragon spacecraft family, which both currently deliver payloads into Earth orbit.
SpaceX's achievements include the first privately funded liquid-propellant rocket to reach orbit (Falcon 1 in 2008);[9] the first privately funded company to successfully launch, orbit, and recover a spacecraft (Dragon in 2010); the first private company to send a spacecraft to the International Space Station (Dragon in 2012);[10] the first propulsive landing for an orbital rocket (Falcon 9 in 2015); and the first reuse of an orbital rocket (Falcon 9 in 2017). As of March 2017, SpaceX has since flown ten missions to the International Space Station (ISS) under a cargo resupply contract.[11] NASA also awarded SpaceX a further development contract in 2011 to develop and demonstrate a human-rated Dragon, which would be used to transport astronauts to the ISS and return them safely to Earth.[12]
SpaceX announced in 2011 that they were beginning a privately funded reusable launch system technology development program. In December 2015, a first stage was flown back to a landing pad near the launch site, where it successfully accomplished a propulsive vertical landing. This was the first such achievement by a rocket for orbital spaceflight.[13] In April 2016, with the launch of CRS-8, SpaceX successfully vertically landed a first stage on an ocean drone-ship landing platform.[14] In May 2016, in another first, SpaceX again landed a first stage, but during a significantly more energetic geostationary transfer orbit mission.[15] In March 2017, SpaceX became the first to successfully re-launch and land the first stage of an orbital rocket.[16]
In September 2016, CEO Elon Musk unveiled the mission architecture of the Interplanetary Transport System program, an ambitious privately funded initiative to develop spaceflight technology for use in manned interplanetary spaceflight, and which, if demand emerges, could lead to sustainable human settlements on Mars over the long term. This is the main purpose this System was designed for.[17][18] In 2017, Elon Musk announced that the company had been contracted by two private individuals to send them in a Dragon spacecraft on a free return trajectory around the Moon.[19][20][21] Provisionally launching in 2018, this could become the first instance of lunar tourism.
History[edit]
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In 2001, Elon Musk conceptualized Mars Oasis, a project to land a miniature experimental greenhouse and grow plants on Mars, "so this would be the furthest that life’s ever traveled"[22] in an attempt to regain public interest in space exploration and increase the budget of NASA.[23][24][25] Musk tried to buy cheap rockets from Russia but returned empty-handed after failing to find rockets for an affordable price.[26][27]
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On the flight home, Musk realized that he could start a company that could build the affordable rockets he needed.[27] According to early Tesla and SpaceX investor Steve Jurvetson,[28] Musk calculated that the raw materials for building a rocket actually were only 3 percent of the sales price of a rocket at the time. By applying vertical integration,[26] producing around 85% of launch hardware in-house,[29][30] and the modular approach from software engineering, SpaceX could cut launch price by a factor of ten and still enjoy a 70 percent gross margin.[31] SpaceX started with the smallest useful orbital rocket, instead of building a more complex and riskier launch vehicle, which could have failed and bankrupted the company.[32]
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In early 2002, Musk was seeking staff for his new space company, soon to be named SpaceX. Musk approached rocket engineer Tom Mueller (now SpaceX's CTO of Propulsion) and Mueller agreed to work for Musk, and thus SpaceX was born.[33] SpaceX was first headquartered in a warehouse in El Segundo, California. The company has grown rapidly since it was founded in 2002, growing from 160 employees in November 2005 to 1,100 in 2010,[34][35] 3,800 employees and contractors by October 2013,[36] and near 5,000 by late 2015.[37][38] As of April 2017, the company has nearly 6,000 employees.[39]In 2016, Musk gave a speech at the International Astronautical Congress, where he explained that the US government regulates rocket technology as an "advanced weapon technology", making it unfortunately and prohibitively difficult to hire non-Americans.[40]
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At year-end 2012, SpaceX had over 40 launches on its manifest representing about $4 billion in contract revenue, with many of those contracts already making progress payments to SpaceX. The contracts included both commercial and government (NASA/DOD) customers.[41] As of December 2013, SpaceX had a total of 50 future launches under contract; two-thirds of them were for commercial customers.[42][43] In late 2013, space industry media began to comment on the phenomenon that SpaceX prices are undercutting the major competitors in the commercial comsat launch market—the Ariane 5 and Proton-M[44]—at which time SpaceX had at least 10 further geostationary orbit flights on its books.[43]
In September 2017, Elon Musk released first prototype images of their space suits to be used in future missions. The suit is in testing phase and it is designed to cope with 2 ATM pressure in vacuum.[1][45]
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Goals[edit]
Musk has stated that one of his goals is to improve the cost and reliability of access to space, ultimately by a factor of ten.[46] The company plans in 2004 called for "development of a heavy lift product and even a super-heavy, if there is customer demand" with each size increase resulting in a significant decrease in cost per pound to orbit. CEO Elon Musk said: "I believe $500 per pound ($1,100/kg) or less is very achievable."[47]
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A major goal of SpaceX has been to develop a rapidly reusable launch system. As of March 2013, the publicly announced aspects of this technology development effort include an active test campaign of the low-altitude, low-speed Grasshopper vertical takeoff, vertical landing (VTVL) technology demonstrator rocket,[48][49][50] and a high-altitude, high-speed Falcon 9 post-mission booster return test campaign where—beginning in mid-2013, with the sixth overall flight of Falcon 9—every first stage will be instrumented and equipped as a controlled descent test vehicle to accomplish propulsive-return over-water tests.[51] SpaceX COO Gwynne Shotwell said at the Singapore Satellite Industry Forum in summer 2013 "If we get this [reusable technology] right, and we’re trying very hard to get this right, we’re looking at launches to be in the US$5 to 7 million range, which would really change things dramatically."[52]
Musk stated in a 2011 interview that he hopes to send humans to Mars' surface within 10–20 years.[53] In 2010, Musk's calculations convinced him that the colonization of Mars was possible.[54] In June 2013, Musk used the descriptor "Mars Colonial Transporter" (only later changed to "Interplanetary Transport System"; see below) to refer to the privately funded development project to design and build a spaceflight system of rocket engines, launch vehicles and space capsules to transport humans to Mars and return to Earth.[55] In March 2014, COO Gwynne Shotwell said that once the Falcon Heavy and Dragon 2 crew version are flying, the focus for the company engineering team will be on developing the technology to support the transport infrastructure necessary for Mars missions.[56]
Achievements[edit]
Landmark achievements of SpaceX include:[57]
- The first privately funded liquid-fueled rocket to reach orbit (Falcon 1 Flight 4 — September 28, 2008)
- The first privately funded company to successfully launch, orbit, and recover a spacecraft (Falcon 9 Flight 2 — December 9, 2010)
- The first private company to send a spacecraft to the International Space Station (Falcon 9 Flight 3 — May 25, 2012)
- The first private company to send a satellite into geosynchronous orbit (Falcon 9 Flight 7 — December 3, 2013)
- The first landing of an orbital rocket's first stage on land (Falcon 9 Flight 20 — December 22, 2015)
- The first landing of an orbital rocket's first stage on an ocean platform (Falcon 9 Flight 23 — April 8, 2016)
- The first relaunch and landing of a used orbital rocket (Falcon 9 Flight 32 — March 30, 2017)[58]
- The first controlled flyback and recovery of a payload fairing (Falcon 9 Flight 32 — March 30, 2017)[59]
- The first reflight of a commercial cargo spacecraft. (Falcon 9 Flight 35 — June 3, 2017)[60]
In December 2015, SpaceX launched an upgraded Falcon 9 rocket from Cape Canaveral Air Force Station into Low Earth orbit, on a mission designated Flight 20. After completing its primary burn, the first stage of the multistage rocket detached from the second stage as usual. The first stage then fired three of its engines to send it back to Cape Canaveral, where it achieved the world's first successful landing of a rocket that was used for an orbital launch.[61]
The upgraded Falcon 9 rocket is currently the only space launch system that uses densified propellants. SpaceX successfully re-introduced this technology with the aforementioned Flight 20. Before, propellant densification had been used only on some ICBMs, which are no longer in service, and the (unsuccessful) Soviet lunar rocket N1.[62]
Setbacks[edit]
In March 2013, a Dragon spacecraft in orbit developed issues with its thrusters. Due to blocked fuel valves, the craft was unable to properly control itself. SpaceX engineers were able to remotely clear the blockages. Because of this issue, the craft arrived at and docked with the International Space Station one day later than expected.
In June 2015, CRS-7 launched a Dragon capsule atop a Falcon 9 to resupply the International Space Station. All telemetry readings were nominal until 2 minutes and 19 seconds into the flight, when a loss of helium pressure was detected and a cloud of vapor appeared outside the second stage. A few seconds after this, the second stage exploded. The first stage continued to fly for a few seconds before disintegrating due to aerodynamic forces. The capsule was thrown off and survived the explosion, transmitting data until it was destroyed on impact.[63] Later it was revealed that the capsule could have landed intact if it had software to deploy its parachutes in case of a launch mishap.[64] The problem was discovered to be a failed 2-foot-long steel strut purchased from a supplier to hold a helium pressure vessel that broke free due to the force of acceleration.[65] This caused a breach and allowed high-pressure helium to escape into the low-pressure propellant tank, causing the failure. The Dragon software issue was also fixed in addition to an analysis of the entire program in order to ensure proper abort mechanisms are in place for future rockets and their payload.[66]
In September 2016, a Falcon 9 exploded during a propellant fill operation for a standard pre-launch static fire test.[67][68] The payload, the Spacecom Amos-6 communications satellite valued at $200 million, was destroyed.[69] Musk described the event as the "most difficult and complex failure" ever in SpaceX's history; SpaceX reviewed nearly 3,000 channels of telemetry and video data covering a period of 35–55 milliseconds for the postmortem.[70] Musk reported the explosion was caused by the liquid oxygen that is used as propellant turning so cold that it solidified and it ignited with carbon composite helium vessels.[71] The rocket explosion sent the company into a four-month launch hiatus while it worked out what went wrong, and SpaceX finally returned to flight in January 2017.[72]
Ownership, funding and valuation[edit]
In August 2008, SpaceX accepted a $20 million investment from Founders Fund.[73] In early 2012, approximately two-thirds of the company were owned by its founder[74] and his 70 million shares were then estimated to be worth $875 million on private markets,[75]which roughly valued SpaceX at $1.3 billion as of February 2012.[76] After the COTS 2+ flight in May 2012, the company private equity valuation nearly doubled to $2.4 billion.[77][78] In January 2015, SpaceX raised $1 billion in funding from Google and Fidelity, in exchange for 8.333% of the company, establishing the company valuation at approximately $12 billion. Google and Fidelity joined the then current investorship group of Draper Fisher Jurvetson, Founders Fund, Valor Equity Partners and Capricorn.[79][80]
As of May 2012, SpaceX had operated on total funding of approximately $1 billion in its first ten years of operation. Of this, private equity provided about $200M, with Musk investing approximately $100M and other investors having put in about $100M (Founders Fund, Draper Fisher Jurvetson, …).[81] The remainder has come from progress payments on long-term launch contracts and development contracts. As of April 2012, NASA had put in about $400–500M of this amount, with most of that as progress payments on launch contracts.[76] By May 2012, SpaceX had contracts for 40 launch missions, and each of those contracts provide down payments at contract signing, plus many are paying progress payments as launch vehicle components are built in advance of mission launch, driven in part by US accounting rules for recognizing long-term revenue.[76]
Congressional testimony by SpaceX in 2017 suggested that the unusual NASA process of "setting only a high-level requirement for cargo transport to the space station [while] leaving the details to industry" had allowed SpaceX to design and develop the Falcon 9 rocket on its own at substantially lower cost. "According to NASA's own independently verified numbers, SpaceX’s development costs of both the Falcon 1 and Falcon 9 rockets were estimated at approximately US$390 million in total. "In 2011, NASA estimated that it would have cost the agency about US$4 billion to develop a rocket like the Falcon 9 booster based upon NASA's traditional contracting processes" and that "a more 'commercial development' approach might have allowed the agency to pay only US$1.7 billion.[82]
In 2012, an initial public offering (IPO) was perceived as possible by the end of 2013,[75] but then Musk stated in June 2013 that he planned to hold off any potential IPO until after the "Mars Colonial Transporter is flying regularly,"[55] and this was reiterated in 2015 indicating that it would be many years before SpaceX would become a publicly traded company,[83] where Musk stated that "I just don’t want [SpaceX] to be controlled by some private equity firm that would milk it for near-term revenue."[84]
In July 2017, the Company raised US$350m at a valuation of US$21 billion.[85]
Spacecraft and flight hardware[edit]
SpaceX currently manufactures two broad classes of rocket engine in-house: the kerosene fueled Merlin engines and the hypergolic fueled Draco/SuperDraco vernier thrusters. The Merlin powers their two main space launch vehicles: the large Falcon 9,[86] which flew successfully into orbit on its maiden launch in June 2010[87] and the super-heavy class Falcon Heavy, which is scheduled to make its first flight in January 2018. SpaceX also manufactures the Dragon, a pressurized orbital spacecraft that is launched on top of a Falcon 9 booster to carry cargo to low Earth orbit, and the follow-on Dragon 2 spacecraft, currently in the process of being human-rated through a variety of design reviews and flight tests that began in 2014.[88][89]
Rocket engines[edit]
Since the founding of SpaceX in 2002, the company has developed three families of rocket engines — Merlin and Kestrel for launch vehicle propulsion, and the Draco control thrusters. SpaceX is currently developing two further rocket engines: SuperDraco and Raptor.
Merlin is a family of rocket engines developed by SpaceX for use on its Falcon rocket family of launch vehicles. Merlin engines use LOX and RP-1 as propellants in a gas-generator power cycle. The Merlin engine was originally designed for sea recovery and reuse. The injector at the heart of Merlin is of the pintle type that was first used in the Apollo Program for the lunar module landing engine. Propellants are fed via a single shaft, dual impeller turbo-pump.
Kestrel is a LOX/RP-1 pressure-fed rocket engine, and was used as the Falcon 1 rocket's second stage main engine. It is built around the same pintle architecture as SpaceX's Merlin engine but does not have a turbo-pump, and is fed only by tank pressure. Its nozzle is ablatively cooled in the chamber and throat, is also radiatively cooled, and is fabricated from a high strength niobium alloy.
Draco are hypergolic liquid-propellant rocket engines that utilize monomethyl hydrazine fuel and nitrogen tetroxide oxidizer. Each Draco thruster generates 400 newtons (90 lbf) of thrust.[90] They are used as reaction control system (RCS) thrusters on the Dragon spacecraft.[91] SuperDraco engines are a much more powerful version of the Draco thrusters, which will be initially used as landing and launch escape system engines on the version 2 Dragon spacecraft, Dragon 2.
Raptor is a new family of methane-fueled full flow staged combustion cycle engines to be used in its future Interplanetary Transport System. Development versions have been test fired.[92]
Falcon launch vehicles[edit]
Since 2010, SpaceX has flown all its missions on the Falcon 9. They are also actively developing the Falcon Heavy, and previously developed and flew the Falcon 1 pathfinder vehicle.
Falcon 1 was a small rocket capable of placing several hundred kilograms into low earth orbit.[87] It functioned as an early test-bed for developing concepts and components for the larger Falcon 9.[87] Falcon 1 attempted five flights between 2006 and 2009. On September 28, 2008, on its fourth attempt, the Falcon 1 successfully reached orbit, becoming the first privately funded, liquid-fueled rocket to do so.[93]
Falcon 9 is an EELV-class medium-lift vehicle capable of delivering up to 22,800 kilograms (50,265 lb) to orbit, and is intended to compete with the Delta IV and the Atlas V rockets, as well as other launch providers around the world. It has nine Merlin engines in its first stage.[94] The Falcon 9 v1.0 rocket successfully reached orbit on its first attempt on June 4, 2010. Its third flight, COTS Demo Flight 2, launched on May 22, 2012, and was the first commercial spacecraft to reach and dock with the International Space Station.[95] The vehicle was upgraded to Falcon 9 v1.1 in 2013 and again in 2015 to the current Falcon 9 Full Thrust version. As of March 2017, Falcon 9 vehicles have flown 30 successful missions with two failures, one after launch and the other during fueling for a routine pre-launch static fire.
In 2011, SpaceX began development of the Falcon Heavy, a heavy-lift rocket configured using a cluster of three Falcon 9 first stage cores with a total 27 Merlin 1D engines and propellant crossfeed.[96][97] The first stage would be capable of lifting 63,957 kilograms (141,100 lb) to LEO with the 27 Merlin 1D engines producing 22,819kN of thrust at sea level, and 24,681 kN in space.[98] When SpaceX finishes development and the rocket is launched, the Falcon Heavy will be the world's most powerful rocket in operation.[99]SpaceX is aiming for the first demonstration flight of the Falcon Heavy in January 2018, delivering a payload consisting of Musk's personal Tesla Roadster (playing Space Oddity, by David Bowie) into Mars orbit.[100]
Dragon capsules[edit]
In 2005, SpaceX announced plans to pursue a human-rated commercial space program through the end of the decade.[101] The Dragon is a conventional blunt-cone ballistic capsule which is capable of carrying cargo or up to seven astronauts into orbit and beyond.[102][102]
In 2006, NASA announced that the company was one of two selected to provide crew and cargo resupply demonstration contracts to the ISS under the COTS program.[103] SpaceX demonstrated cargo resupply and eventually crew transportation services using the Dragon.[95]The first flight of a Dragon structural test article took place in June 2010, from Launch Complex 40 at Cape Canaveral Air Force Station during the maiden flight of the Falcon 9 launch vehicle; the mock-up Dragon lacked avionics, heat shield, and other key elements normally required of a fully operational spacecraft but contained all the necessary characteristics to validate the flight performance of the launch vehicle.[104] An operational Dragon spacecraft was launched in December 2010 aboard COTS Demo Flight 1, the Falcon 9's second flight, and safely returned to Earth after two orbits, completing all its mission objectives.[88] In 2012, Dragon became the first commercial spacecraft to deliver cargo to the International Space Station,[95] and has since been conducting regular resupply services to the ISS.[105]
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In 2009 and 2010, Musk suggested on several occasions that plans for a human-rated variant of Dragon were proceeding and had a 2- to 3-year time line to completion.[106][107] In April 2011, NASA issued a $75 million contract, as part of its second-round commercial crew development (CCDev) program, for SpaceX to develop an integrated launch escape system for Dragon in preparation for human-rating it as a crew transport vehicle to the ISS.[108] This Space Act Agreement runs from April 2011 until May 2012, when the next round of contracts are to be awarded.[108] NASA approved the technical plans for the system in October 2011, and SpaceX began building prototype hardware.[109]
SpaceX plans to launch its Dragon 2 spacecraft on an unmanned test flight to the ISS in November 2017, and later in 2018, a crewed Dragon will send US astronauts to the ISS for the first time since the retirement of the Space Shuttle. In February 2017 SpaceX announced that two would-be space tourists had put down "significant deposits" for a mission which would see the two private astronauts fly on board a Dragon capsule to the moon and back again. At the press conference announcing the mission Elon Musk said that the cost of the mission would be "comparable" to that of sending an astronaut to the International Space Station; about $70 million US dollars per astronaut in 2017.[19] The mission is slated for late 2018.[110]
In addition to SpaceX's privately funded plans for an eventual Mars mission, NASA Ames Research Center had developed a concept called Red Dragon: a low-cost Mars mission that would use Falcon Heavy as the launch vehicle and trans-Martian injection vehicle, and the Dragon capsule to enter the Martian atmosphere. The concept was originally envisioned for launch in 2018 as a NASA Discovery mission, then alternatively for 2022, but as of September 2015 it has not been yet formally submitted for funding within NASA.[111] The objectives of the mission would be return the samples from Mars to Earth at a fraction of the cost of the NASA own return-sample mission now projected at 6 billion dollars.[111] In April 2016, SpaceX announced its plan to launch a modified Dragon lander to Mars by 2018. This project is part of a public-private partnership contract between NASA and SpaceX. In early 2017, SpaceX has pushed the mission to the 2020 launch window to have more time to dedicate to other projects such as the Falcon Heavy and the Dragon 2 (Crew Dragon) spacecraft.[112] Later in 2017 cancellation of Red Dragon was announced; SpaceX will concentrate on landing a much larger ship on Mars [113].
In September 2017 it has been reported that SpaceX has completed testing on the first stage cores for its Falcon Heavy rocket.[114]
Research and development[edit]
SpaceX is actively pursuing several different research and development programs. Most notable are the programs intended to develop reusable launch vehicles, an interplanetary transport system, and a global telecommunications network.
SpaceX has on occasion developed new engineering development technologies to enable it to pursue its various goals. For example, at the 2015 GPU Technology Conference, SpaceX revealed their own computational fluid dynamics (CFD) software to improve the simulation capability of evaluating rocket engine combustion design
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