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BFR[1]:2:35 is SpaceX's privately-funded next-generation launch vehicle and spacecraft announced by Elon Musk in September 2017.[3][4] It includes reusable launch vehicles and spacecraft that are intended by SpaceX to replace all of the company's current hardware by the early 2020s, ground infrastructure for rapid launch and relaunch, and zero-gravity propellant transfer technology to be deployed in low Earth orbit. The new vehicles are much larger than the existing SpaceX fleet, and the large payload to low-Earth orbit (LEO) of 150,000 kg (330,000 lb) making it a super heavy-lift launch vehicle.

BFR
SpaceX BFR launch vehicle.jpg
SpaceX rendering of BFR
Function Mars colonization,
Earth-Lunar transport,
Intercontinental transport,
Orbital launcher[1]
Manufacturer SpaceX
Country of origin United States
Size
Height 106 m (348 ft) [1]
Diameter 9 m (30 ft)
Mass 4,400,000 kg (9,700,000 lb)
Stages 2
Capacity
Payload to LEO 150,000 kg (330,000 lb) reusable
[1]
Payload to Earth (return) 50,000 kg (110,000 lb) [1]
Launch history
Status In development
Launch sites
First stage – Booster
Length 58 m (190 ft) [1]
Diameter 9 m (30 ft)
Gross mass 3,065,000 kg (6,757,000 lb)
Engines 31 Raptor
Thrust 52.7 MN (11,800,000 lbf) (sea level) [1]
Specific impulse 330 s (3.2 km/s) (sea level)
each engine
Fuel Subcooled CH
4
 / LOX
Second stage – Spaceship
Length 48 m (157 ft) [1]
Diameter 9 m (30 ft)
Empty mass 85,000 kg (187,000 lb)
Gross mass 1,335,000 kg (2,943,000 lb)
Propellant mass 240,000 kg (530,000 lb) CH
4
860,000 kg (1,900,000 lb)LOX
Engines 7 Raptor (4 vacuum, 3 sea level) [2]
Thrust 12.7 MN (2,900,000 lbf) total
Specific impulse

375 s (3.68 km/s) (vacuum)
each, outer 4 engines
356 s (3.49 km/s) (vacuum)
each, inner 3 engines


330 s (3.2 km/s) (sea level) [1]
each, inner 3 engines
Fuel Subcooled CH
4
 / LOX

The BFR system is planned to replace both Falcon 9 and Falcon Heavy launch vehicles, as well as the Dragon spacecraft, initially aiming at the Earth-orbit launch market, but explicitly adding substantial capability to support long-duration spaceflight in the cislunar and Mars mission environments.[1] SpaceX intends this approach to bring significant cost savings which will help the company justify the development expense of designing and building the BFR system.

SpaceX had initially envisioned a larger design known as the ITS launch vehicle, which was presented in September 2016 as part of Musk's vision for an interplanetary transport system.[5] The ITS range of vehicles were designed with a 12-meter (39 ft) core diameter,[6] and the BFR design was scaled down to 9 meters (30 ft).[1] While the ITS had been solely aimed at Mars transit and other interplanetary uses, SpaceX pivoted in 2017 to a plan that would support all SpaceX launch service provider capabilities with a single range of vehicles: Earth-orbit, Lunar-orbit, interplanetary missions, and even intercontinental passenger transport on Earth.[1][7]

Development work began in 2012 on the Raptor rocket engines which are to be used for both stages of the BFR launch vehicle, and engine testing began in 2016. New rocket engine designs are typically considered one of the longest of the development subprocesses for new launch vehicles and spacecraft. Tooling for the main tanks has been ordered and a facility to build the vehicles is under construction; construction of the first ship is scheduled to begin in the second quarter of 2018.[1] The company publicly stated an aspirational goal for initial Mars-bound cargo flights of BFR launching as early as 2022, followed by the first crewed BFR flight one synodic period later, in 2024.[3]

Contents

HistoryEdit

As early as 2007, Elon Musk stated a personal goal of eventually enabling human exploration and settlement of Mars,[8][9] although his personal public interest in Mars goes back at least to 2001.[10] Bits of additional information about the mission architecture were released in 2011–2015, including a 2014 statement that initial colonists would arrive at Mars no earlier than the middle of the 2020s.[11] Company statements in 2016 indicated that SpaceX was "being intentionally fuzzy about the timeline ... We're going to try and make as much progress as we can with a very constrained budget."[12][13]

Musk stated in a 2011 interview that he hoped to send humans to Mars's surface within 10–20 years,[9] and in late 2012 he stated that he envisioned a Mars colony of tens of thousands with the first colonists arriving no earlier than the middle of the 2020s.[11][14][15]

Engine development begins; high-level vehicle plans begin to be publicly releasedEdit

In March 2012, news accounts asserted that a Raptor upper-stage engine had begun development, but that details would not be released.[16] In October 2012, Musk publicly stated a high-level plan to build a second reusable rocket system with capabilities substantially beyond the Falcon 9/Falcon Heavy launch vehicles on which SpaceX had by then spent several billion US dollars.[17] This new vehicle was to be "an evolution of SpaceX's Falcon 9 booster ... 'much bigger'." But Musk indicated that SpaceX would not be speaking publicly about it until 2013.[11][18]

In June 2013, Musk stated that he intended to hold off any potential IPO of SpaceX shares on the stock market until after the "Mars Colonial Transporter is flying regularly."[19][20]

In August 2014, media sources speculated that the initial flight test of the Raptor-driven super-heavy launch vehicle could occur as early as 2020, in order to fully test the engines under orbital spaceflight conditions; however, any colonization effort was reported to continue to be "deep into the future".[21][22]

In early 2015, Musk said that he hoped to release details in late 2015 of the "completely new architecture" for the system that would enable the colonization of Mars. Those plans were delayed,[23][24][25][13][26] and the name of the system architecture was changed to Interplanetary Transport System (ITS) in mid-September 2016.[5]

On 27 September 2016, at the 67th annual meeting of the International Astronautical Congress, Musk unveiled substantial details of the design for the transport vehicles—including the very large size (12 meters (39 ft) core diameter),[6]), construction material, number and type of engines, thrust, cargo and passenger payload capabilities, in-orbit propellant-tanker refills, representative transit times, etc.—as well as details of portions of the Mars-side and Earth-side infrastructure that SpaceX intended to build to support a set of three flight vehicles. The three distinct vehicles that made up the ITS launch vehicle in the 2016 design were the:[1]

  • ITS booster, the first-stage of the launch vehicle
  • ITS spaceship, a second-stage and long-duration in-space spacecraft
  • ITS tanker, an alternative second-stage designed to carry more propellant for refueling other vehicles in space

In addition, Musk championed a larger systemic vision, a vision for a bottom-up emergent order of other interested parties—whether companies, individuals, or governments—to utilize the new and radically lower-cost transport infrastructure that SpaceX would endeavor to build in order to help build a sustainable human civilization on Mars by innovating and meeting the demand that such a growing venture would occasion.[27][28]

In the November 2016 plan, SpaceX indicated it would fly its earliest research spacecraft missions to Mars using its Falcon Heavy launch vehicle and a specialized modified Dragon spacecraft, called "Red Dragon" prior to the completion, and first launch, of any ITS vehicle. Later Mars missions using ITS were slated then to begin no earlier than 2022.[29]

By February 2017, the earliest launch of any SpaceX mission to Mars was to be 2020, two years later than the previously mentioned 2018 Falcon Heavy/Dragon2 exploratory mission.[30] In July 2017, SpaceX announced it would no longer plan to use a propulsively-landed "Red Dragon" spacecraft on the early missions, as had been previously announced.[31]

In July 2017, SpaceX made public plans to build a much smaller launch vehicle and spacecraft prior to building the ITS launch vehicle that had been unveiled nine months earlier for just the beyond Earth orbit part of future SpaceX launch service offerings. Musk indicated that the architecture has "evolved quite a bit" since the November 2016 articulation of the comprehensive Mars architecture. A key driver of the new architecture is to make the new system useful for substantial Earth-orbit and cislunar launches so that the new system might pay for itself, in part, through economic spaceflight activities in the near-Earth space zone.[32] "Serious development of BFR" began in 2017.[1]:15:22

Announcement of the BFREdit

On 29 September 2017 at the 68th annual meeting of the International Astronautical Congress in Adelaide, South Australia, SpaceX unveiled the new smaller vehicle architecture. Musk said "we are searching for the right name, but the code name, at least, is BFR."[1] The new launch vehicle system is a 9-meter (30 ft) diameter technology, using methalox-fueled Raptor rocket engine technology directed initially at the Earth-orbit and cislunar environment, later, being used for Mars missions.[1][3]

Aerodynamics of the BFR second stage changed from the 2016-design ITS launch vehicle. The new design is cylindrical with a small delta wing at the rear end which includes a split flap for pitch and roll control. The delta wing and split flaps are needed to expand the mission envelope to allow the ship to land in a variety of atmospheric densities (no, thin, or heavy atmosphere) with a wide range of payloads (small, heavy, or none) in the nose of the ship.[1]:18:05–19:25 The cylindrical shape is for mass optimization. There are three versions of the ship: BFR crew, BFR cargo, BFR tanker. The first two are primarily destined to fly to Mars.[citation needed] The cargo version can also be used to launch satellites to Low Earth Orbit.

After retanking in a high-elliptic Earth orbit the spaceship is being designed to be able to land on the Moon and return to Earth without further refueling.[1]:31:50 The most surprising announcement was to use BFR as a point-to-point transfer system for people on Earth. Musk expects ticket price to be on par with a full-fare economy plane ticket for the same distance.

As of September 2017, Raptor engines had been tested for a combined total of 1200 seconds of test firing time over 42 main engine tests. The longest test was 100 seconds, which is limited by the size of the propellant tanks at the SpaceX ground test facility. The test engine operates at 20 MPa (200 bar; 2,900 psi) pressure. The flight engine is aimed for 25 MPa (250 bar; 3,600 psi), and SpaceX expects to achieve 30 MPa (300 bar; 4,400 psi) in later iterations.[1]

Testing of the BFR vehicle is expected to begin with short suborbital hops of the full-scale ship, likely to just a few hundred kilometers altitude and lateral distance.[33]

By September 2017, SpaceX had already started building launch vehicle components. "The tooling for the main tanks has been ordered, the facility is being built, we will start construction of the first ship [in the second quarter of 2018.]" Musk is hoping to be ready for an initial Mars launch in five years, in order to make the 2022 Mars conjunction window.[1] In November 2017, SpaceX president and COO Gwynne Shotwell indicated that approximately half of all current development work on BFR is on Raptor engine development.[34]

The aspirational goal is the first two cargo missions to Mars in 2022, with the goal to "confirm water resources and identify hazards" while putting "power, mining, and life support infrastructure" in place for future flights, followed by four ships in 2024, two crewed BFR spaceships plus two cargo-only ships bringing additional equipment and supplies with the goal of setting up the propellant production plant.[1]

NomenclatureEdit

The descriptor for the large SpaceX Mars rocket has varied over the past five years that SpaceX has publically-released information about the project. BFR is the current code name for SpaceX's privately-funded launch vehicle announced by Elon Musk in September 2017,[1]:2:39[3][4][35] which may have originated from Big Falcon Rocket[36][37] or Big Fucking Rocket.[37][38][39]

From September 2016 through August 2017, the overall system was referred to by SpaceX as the Interplanetary Transport System and the launch vehicle itself as the ITS launch vehicle. Beginning in mid-2013, and prior to September 2016, SpaceX had referred to both the architecture and the vehicle as the Mars Colonial Transporter.

Scope of BFR missionsEdit

The BFR launch vehicle is planned to replace all existing SpaceX vehicles and spacecraft in the early 2020s. SpaceX cost estimation has led the company to conclude that BFR launches will be cheaper per launch than launches of the existing vehicles and even cheaper than launches of the retired Falcon 1. This is partly due to the full reusability of all parts of BFR, but also due to precision landing of the booster on its launch mount and industry-leading launch operations. More specifically, both Falcon 9 and Falcon Heavy launch vehicles and the Dragon spacecraft being flown today will be replaced in the operational SpaceX fleet during the early 2020s.[40][1]:24:50–27:05

Flight missions of BFR will thus aim at the:[40]

DescriptionEdit

The BFR design consists of a combination of several elements that are key—according to Musk—to making long-duration beyond Earth orbit (BEO) spaceflights possible by reducing the cost per ton delivered to low-Earth orbit (LEO) and to/from BEO destinations, importantly while serving all use cases for the conventional LEO spaceflight market as well so that SpaceX can justify the high development cost of the next-generation launch vehicle technology.[1][7][43] The new fully-reusable super-heavy-lift BFR consists of a:[1]

  • reusable booster stage, the BFR booster, and a
  • reusable integrated second-stage-with-spacecraft that will be built in at least three versions:
    • BFR spaceship, a large, long-duration, spacecraft capable of carrying passengers or cargo to or through space to interplanetary destinations, as well as to LEO or Earth-to-Earth destinations
    • Earth-orbit cargo-only propellant tanker—the BFR tanker to support the refilling of propellants in orbit, specifically to enable the long-duration spaceship to expend most all of its propellant load during the launch to low-Earth orbit while it serves as the second stage of the launch vehicle, and then—after refilling on orbit—provide the significant amount of energy necessary to put the spacecraft onto an interplanetary trajectory.
    • BFR satellite delivery spacecraft, a version with a large cargo bay door that can open in space to facilitate the placement of a variety of smaller spacecraft—even very large spacecraft like the Hubble Space Telescope—in to whatever orbit is desired.

The combination of a second-stage of a launch vehicle with a long-duration spacecraft is unusual for any space mission architecture, and has not been seen in previous spaceflight technology. Use of such technology is completely dependent on the refilling of propellants in orbit to enable transport to beyond Earth orbit destinations.

The BFR spaceship, BFR tanker, and the BFR satellite delivery spacecraft share the same outer mold line. The second-stage/ship can also return to the launch location, with design capability to withstand multiple engine out events and land on a single engine, and so can withstand an engine-out anomaly at any point in the reentry, descent and landing sequence.[1]

The functioning of the system on BEO interplanetary destinations like Mars will require propellant production on the surface of Mars to enable the return trip back to Earth and support reuse of the spacecraft, enabling significantly lower cost to transport cargo and passengers to distant destinations. Lunar destinations could be serviced without Lunar-propellant depots, as long as the ship is retanked in a high-elliptical orbit before the Lunar transit begins.[1]

The major characteristics of the launch vehicle include:[1][44][45]

  • Completely reusable, both stages
  • Booster returns to launch mount; second-stage/ship can also return to the launch location. Both use retropropulsive landing.
  • Expected landing reliability on a par with major airliners
  • Automated rendezvous and docking
  • On-orbit propellant transfer from BFR tanker to BFR spaceship
  • The ship and its payload can transit to the Moon or Mars after on-orbit propellant loading
  • Reusable heat-shield technology
  • The BFR spaceship contains 825 m3 (29,100 cu ft) of pressurized volume; could be configured with up to 40 cabins, large common areas, central storage, galley, and a solar storm shelter in Mars transit configuration.
Specifications[1][45]
Complete BFR booster BFR spaceship/tanker/
sat-delivery vehicle
LEO Payload 150,000 kg (330,000 lb)
Return Payload 50,000 kg (110,000 lb)
Cargo Volume 825 m3 (29,100 cu ft) N/A 825 m3 (29,100 cu ft)
(spaceship)
Diameter 9 m (30 ft)
Length 106 m (348 ft) 58 m (190 ft) 48 m (157 ft)
Maximum weight 4,400,000 kg (9,700,000 lb) 1,335,000 kg (2,943,000 lb)
Propellant Capacity CH
4
– 240,000 kg (530,000 lb)
O
2
– 860,000 kg (1,900,000 lb)
Empty weight 85,000 kg (187,000 lb)
Engines 31 × SL Raptors 3 × SL + 4 × vacuum Raptors[2]
Thrust 52.7 MN (11,800,000 lbf) 12.7 MN (2,900,000 lbf) total

The Raptor engine characteristics include:[1]

  • flight engine designed to operate at 25 MPa (250 bar; 3,600 psi) of chamber pressure and achieve 30 MPa (300 bar; 4,400 psi) in later iterations.
  • extremely focused on reliability.[45]

See alsoEdit

ReferencesEdit

  1. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae Elon Musk (29 September 2017). Becoming a Multiplanet Species (video). 68th annual meeting of the International Astronautical Congress in Adelaide, Australia: SpaceX. Retrieved 2017-12-14 – via YouTube. 
  2. ^ a b Foust, Jeff (15 October 2017). "Musk offers more technical details on BFR system". SpaceNews. Retrieved 2017-10-15. [Musk] added that, since the presentation last month, SpaceX has revised the design of the BFR spaceship to add a "medium area ratio" Raptor engine to its original complement of two engines with sea-level nozzles and four with vacuum nozzles. That additional engine helps enable that engine-out capability ... and will "allow landings with higher payload mass for the Earth to Earth transport function." 
  3. ^ a b c d Foust, Jeff (29 September 2017). "Musk unveils revised version of giant interplanetary launch system". SpaceNews. Retrieved 2017-10-01. 
  4. ^ a b Harwood, William (29 September 2017). "Elon Musk revises Mars plan, hopes for boots on ground in 2024". SpaceflightNow. Retrieved 2017-09-30. The new rocket is still known as the BFR, a euphemism for 'Big (fill-in-the-blank) Rocket.' The reusable BFR will use 31 Raptor engines burning densified, or super-cooled, liquid methane and liquid oxygen to lift 150 tons, or 300,000 pounds, to low-Earth orbit, roughly equivalent to NASA’s Saturn 5 moon rocket. 
  5. ^ a b Berger, Eric (18 September 2016). "Elon Musk scales up his ambitions, considering going "well beyond" Mars". Ars Technica. Retrieved 2016-09-19. 
  6. ^ a b Chang, Kenneth (27 September 2016). "Elon Musk's Plan: Get Humans to Mars, and Beyond". New York Times. Retrieved 27 September 2016. 
  7. ^ a b Dent, Steve (29 September 2017). "Elon Musk's Mars dream hinges on a giant new rocket". Engadget. Retrieved 2017-12-09. 
  8. ^ Hoffman, Carl (22 May 2007). "Elon Musk Is Betting His Fortune on a Mission Beyond Earth's Orbit". Wired Magazine. Retrieved 2014-03-14. 
  9. ^ a b Murray, Alan (22 April 2011). "Elon Musk: I'll Put a Man on Mars in 10 Years". WSJ.com (video). The Wall Street Journal. Archived from the original on 1 December 2011. Retrieved 2011-12-01 – via Market Watch. 
  10. ^ Richardson, Derek (27 September 2016). "Elon Musk Shows Off Interplanetary Transport System". Spaceflight Insider. Retrieved 3 October 2016. 
  11. ^ a b c "Huge Mars Colony Eyed by SpaceX Founder". Discovery News. 13 December 2012. Archived from the original on 2014-11-15. Retrieved 2014-03-14. 
  12. ^ Foust, Jeff (27 September 2016). "SpaceX's Mars plans call for massive 42-engine reusable rocket". SpaceNews. Retrieved 2016-10-14. Musk stated it's possible that the first spaceship would be ready for tests in four years, with the booster ready a few years after that, but he shied away from exact schedules in his presentation. 'We're kind of being intentionally fuzzy about the timeline,' he said. 'We're going to try and make as much progress as we can with a very constrained budget.' 
  13. ^ a b Davenport, Christian (13 June 2016). "Elon Musk provides new details on his 'mind blowing' mission to Mars". Washington Post. Retrieved 2016-06-14. 
  14. ^ Carroll, Rory (17 July 2013). "Elon Musk's mission to Mars". TheGuardian. Retrieved 2014-02-05. 
  15. ^ Messier, Doug (5 February 2014). "Elon Musk Talks ISS Flights, Vladimir Putin and Mars". Parabolic Arc. 
  16. ^ Rosenberg, Zach (16 March 2012). "SpaceX readies upgraded engines". Flightglobal. Retrieved 17 January 2018. SpaceX is in the midst of a variety of ambitious engine programmes, including the Merlin 2, a significant modification of the Merlin 1 series, and the Raptor upper stage engine. Details of both projects are tightly held. 
  17. ^ Zach Rosenberg (15 October 2012). "SpaceX aims big with massive new rocket". Flight Global. Retrieved 2015-10-28. 
  18. ^ Coppinger, Rod (23 November 2012). "Huge Mars Colony Eyed by SpaceX Founder Elon Musk". Space.com. Retrieved 2013-06-10. The fully reusable rocket that Musk wants to take colonists to Mars is an evolution of SpaceX's Falcon 9 booster ... 'It's going to be much bigger [than Falcon 9], but I don’t think we’re quite ready to state the payload. We’ll speak about that next year,' Musk said. ... 'Vertical landing is an extremely important breakthrough — extreme, rapid reusability.' 
  19. ^ Schaefer, Steve (6 June 2013). "SpaceX IPO Cleared For Launch? Elon Musk Says Hold Your Horses". Forbes. Retrieved 2013-06-10. 
  20. ^ Ciaccia, Chris (6 June 2013). "SpaceX IPO: 'Possible in the Very Long Term'". The Street. Retrieved 2013-06-10. 
  21. ^ Boyle, Alan (5 January 2015). "Coming Soon From SpaceX's Elon Musk: How to Move to Mars". NBC News. Retrieved 8 January 2015. The Mars transport system will be a completely new architecture. Am hoping to present that towards the end of this year. Good thing we didn't do it sooner, as we have learned a huge amount from Falcon and Dragon. 
  22. ^ Bergin, Chris (29 August 2014). "Battle of the Heavyweight Rockets -- SLS could face Exploration Class rival". NASAspaceflight.com. Retrieved 2014-08-30. 
  23. ^ Heath, Chris (12 December 2015). "How Elon Musk Plans on Reinventing the World (and Mars)". GQ. Retrieved 2015-12-12. 
  24. ^ 2016 StartmeupHK Venture Forum - Elon Musk on Entrepreneurship and Innovation. StartmeupHK Venture Forum--2016 (video). Invest Hong Kong. 26 January 2016. Event occurs at 30:15-31:40. Retrieved 2016-01-26 – via YouTube. We'll have the next generation rocket and spacecraft, beyond the Falcon and Dragon series ... I'm hoping to describe that architecture later this year at the International Astronautical Congress. which is the big international space event every year. ... first flights to Mars? we're hoping to do that in around 2025 ... nine years from now or thereabouts. 
  25. ^ Boyle, Alan (27 January 2016). "SpaceX's Elon Musk wants to go into space by 2021 and start Mars missions by 2025". GeekWire. Retrieved 2016-01-29. 
  26. ^ Boyle, Alan (27 September 2016). "SpaceX's Elon Musk makes the big pitch for his decades-long plan to colonize Mars". GeekWire. Retrieved 2016-10-03. 
  27. ^ Berger, Eric (28 September 2016). "Musk's Mars moment: Audacity, madness, brilliance—or maybe all three". Ars Technica. Retrieved 2016-10-13. 
  28. ^ Foust, Jeff (10 October 2016). "Can Elon Musk get to Mars?". SpaceNews. Retrieved 2016-10-12. 
  29. ^ Boyle, Alan (10 June 2016). "SpaceX's Elon Musk teases 'dangerous' plan to colonize Mars starting in 2024". GeekWire. Retrieved 2016-08-10. 
  30. ^ Grush, Lauren (17 March 2017). "SpaceX is pushing back the target launch date for its first Mars mission". The Verge. Retrieved 2017-04-09. 
  31. ^ Grush, Loren (19 July 2017). "Elon Musk suggests SpaceX is scrapping its plans to land Dragon capsules on Mars". The Verge. 
  32. ^ Elon Musk (19 July 2017). Elon Musk, ISS R&D Conference (video). ISS R&D Conference, Washington DC, USA. Event occurs at 49:48–51:35. Retrieved 2017-09-13 – via YouTube. the updated version of the Mars architecture: Because it has evolved quite a bit since that last talk. ... The key thing that I figured out is how do you pay for it? if we downsize the Mars vehicle, make it capable of doing Earth-orbit activity as well as Mars activity, maybe we can pay for it by using it for Earth-orbit activity. That is one of the key elements in the new architecture. It is similar to what was shown at IAC, but a little bit smaller. Still big, but this one has a shot at being real on the economic front. 
  33. ^ a b Foust, Jeff (15 October 2017). "Musk offers more technical details on BFR system". SpaceNews. Retrieved 2017-10-15. [the] spaceship portion of the BFR, which would transport people on point-to-point suborbital flights or on missions to the moon or Mars, will be tested on Earth first in a series of short hops. ... a full-scale Ship doing short hops of a few hundred kilometers altitude and lateral distance ... fairly easy on the vehicle, as no heat shield is needed, we can have a large amount of reserve propellant and don’t need the high area ratio, deep space Raptor engines. 
  34. ^ Hanry, Caleb (2017-11-21). "SpaceX aims to follow a banner year with an even faster 2018 launch cadence". SpaceNews. Retrieved 2018-01-15. Shotwell estimated that around 50 percent of the work on BFR is focused on the Raptor engines. 
  35. ^ Fernholz, Tim (29 September 2017). "SpaceX's Elon Musk unveiled a rocket that can fly to the Moon, Mars—and Shanghai". Quartz. Retrieved 2017-09-30. 
  36. ^ SpaceX (12 April 2017). "Artist's Rendering Of The Big Falcon Rocket". SpaceX. Retrieved 2017-10-03. 
  37. ^ a b Pham, Sherisse; Wattles, Jackie (29 September 2017). "Elon Musk is aiming to land spaceships on Mars in 2022". CNNMoney. Retrieved 2017-09-29. 
  38. ^ Grush, Loren (29 September 2017). "Elon Musk plans to put all of SpaceX's resources into its Mars rocket". The Verge. Retrieved 2017-09-29. 
  39. ^ Blewitt, Richard Tyr (29 September 2017). "Elon Musk's plans for the Big Fucking Rocket: Mars, Moon, and Earth". Neowin. Retrieved 29 September 2017. 
  40. ^ a b Gebhardt, Chris (29 September 2017). "The Moon, Mars, & around the Earth – Musk updates BFR architecture, plans". NASASpaceflight.com. Retrieved 2 October 2017. In a move that would have seemed crazy a few years ago, Mr. Musk stated that the goal of BFR is to make the Falcon 9 and the Falcon Heavy rockets and their crew/uncrewed Dragon spacecrafts redundant, thereby allowing the company to shift all resources and funding allocations from those vehicles to BFR. Making the Falcon 9, Falcon Heavy, and Dragon redundant would also allow BFR to perform the same Low Earth Orbit (LEO) and Beyond LEO satellite deployment missions as Falcon 9 and Falcon Heavy – just on a more economical scale as multiple satellites would be able to launch at the same time and on the same rocket thanks to BFR’s immense size. 
  41. ^ BFR Earth to Earth, SpaceX, 28 September 2017, accessed 23 December 2017.
  42. ^ Strauss, Neil (15 November 2017). "Elon Musk: The Architect of Tomorrow". Rolling Stone. Retrieved 15 November 2017. 
  43. ^ Elon Musk (27 September 2016). Making Humans a Multiplanetary Species (video). IAC67, Guadalajara, Mexico: SpaceX. Event occurs at 9:20–10:10. Retrieved 10 October 2016. So it is a bit tricky. Because we have to figure out how to improve the cost of the trips to Mars by five million percent ... translates to an improvement of approximately 4 1/2 orders of magnitude. These are the key elements that are needed in order to achieve a 4 1/2 order of magnitude improvement. Most of the improvement would come from full reusability—somewhere between 2 and 2 1/2 orders of magnitude—and then the other 2 orders of magnitude would come from refilling in orbit, propellant production on Mars, and choosing the right propellant. 
  44. ^ Musk, Elon (September 2017). "transcript: MAKING LIFE INTERPLANETARY. Elon Musk presentation 68th IAC in Adelaide, Australia" (PDF). SpaceX. 
  45. ^ a b c Foust, Jeff (15 October 2017). "Musk offers more technical details on BFR system". SpaceNews. Retrieved 2017-10-15. [Musk wrote,] "The flight engine design is much lighter and tighter, and is extremely focused on reliability."