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The term "commercial space transportation" is evolving from launch vehicles such as Atlas 5 (above) to other ways of moving payloads into orbit and beyond. (credit: ULA) |
by Dallas Bienhoff
Monday, August 19th, 2019
Today, commercial space transport means, above all, a launch in Earth orbit. In the near future, it will include commercial space transportation systems and their supporting infrastructure. In fact, there are currently commercial transportation companies in space. It is possible to book delivery of a payload to the moon on commercial lunar landers that can be consumed today with Astrobotic for $ 1.2 million per kilogram. In addition, Momentus offers non-recoverable space tug services in Earth orbit for small payloads. Reusable space tugs and Moon shuttles with propellant deposits and in-orbit refueling are forthcoming. Commercial space transportation is evolving into more diversified and reusable launching systems, while expanding to encompass orbit transfer vehicles and landing units on the Moon.
Launch systems: more variety and less expensive
The commercial launch is evolving. Today there are many commercial launch companies. Most companies use expendable launchers while SpaceX rockets have reusable boosters. In the near future, launcher suppliers will have reusable first-stage engine compartments, reusable first-stage landing vertically or horizontally, and fully reusable two-stage launchers using vertical or horizontal take-off and landing approaches (Figure 1). 1).
| The commercial launch takes three different directions today. |
SpaceX's Falcon 9 and Falcon Heavy reusable boot stages land vertically at the launch site or on marine barges. Soon, Blue Origin will join SpaceX in its debut with New Glenn with its vertical landing boosters. SpaceX is also developing its Super Heavy / Starliner, a fully reusable two-stage vertical landing launcher.
Other companies are adopting their own approaches to reusability. Rather than recovering the entire first floor, ULA's Vulcan launcher is designed for the recovery of the engine compartment and the first stage avionics compartment. Boeing is collaborating with DARPA in the development of a two-stage launcher comprising a reusable first-stage fender and a consumable second-stage. The rocket takes off vertically and the first floor lands horizontally on a runway. Exodus Space is developing AstroClipper, a fully reusable two-stage horizontal landing launch system.
The Holy Grail for launch is a fully reusable horizontal take-off horizontal take-off orbit single-take-off vehicle. This dream can be just beyond the horizon. Reaction Engines, Ltd. is developing its Synergy Airborne Rocket Engine (SABER) for single-stage, reusable reusable vehicles. At the same time, other companies continue to advance technology and operational concepts to increase launch rates and lower launch costs for the small payload market.
The commercial launch takes three different directions today. The first is already in place and growing: reusable first stages for traditional vertical takeoff rockets. The second is to fully reuse vertical two-stage and one-take vertical take-off and take-off landing concepts. The third direction is to use low-cost expendable vehicles for small payloads by applying innovative materials, manufacturing processes and / or operational approaches. Which solution will win? Maybe there will be a solution per payload class. Perhaps there will be several solutions per payload class, similar to the methods of transport on Earth. More than 100 companies are looking for launch solutions. the most for small payloads. Some will succeed; some will fail. One thing is sure; the future of the commercial launch will be different from what it is today.
The cost savings associated with reusability are somewhat offset by the expense incurred in preparing the vehicle for its next flight. Small payload launchers are less expensive because they are smaller, built with advanced materials and manufacturing approaches, have higher flight rates, deliver payloads only in a low Earth orbit, and have one hand. -d n reduced work.
Figure 1. The commercial launch shifts from non-reusable vehicles to systems with reusable first stages, fully reusable two-stage and single-stage vehicles, and small inexpensive one-way vehicles. |
Commercial transport in space: a new paradigm
Commercial transport in space is in its infancy. Astrobotic has a price displayed for the delivery of small payloads on the Moon. Momentus Space proposes to move payloads to higher Earth orbits from ISS or when they are attached to a payload at launch. Orbit Fab tests equipment on ISS for water deposits in Earth orbit. Altius develops equipment to enable on-orbit service and mating. Interglobal defines intra-orbital transport architecture systems to serve co-orbital space stations. Cislunar Space Development Company defines reusable cislunary vehicles for transporting LEO to the lunar surface and all intermediate points. Reusable space tugs will have the same economic benefits as today's reusable boosters.
Space tugs: life extension and orbit transfer
The extension of the life of satellites, where an attached spacecraft takes over for internal attitude control and retention capabilities, is a first application of space tug. The Northrop Grumman Mission Expansion Vehicle, the Space Space Real Space and the DARPA geosynchronous satellite service (GSR) service are programs offering life extension services (Figure 2). Life Extension tugboats are to be delivered to their customers by launchers and upper floors because they do not have enough propulsion for large orbit transfer maneuvers.
Figure 2. Lifetime extension and robotic maintenance are provided by space-saving tugboats. |
Momentus Space offers commercial space tugs for the delivery of small satellites from the ISS or release point of the launch vehicle. Their Ride family (VIGORIDE, VIGORIDE EXTENDED and ARDORIDE) includes low thrust stages, high specific impulse (Isp), using water as a propellant. The maximum payload masses are 350, 450 and 4000 kilograms, respectively. Transportation can be booked on the Ride Family today on the Momentus website. FERVORIDE, a more efficient space tug for deploying GEO satellites and interplanetary probes, is under development (Figure 3). Momentus Space VIGORIDE can provide more than one kilometer per second of gear shift (delta-V) at a payload of 50 kg, while VIGORIDE EXTENDED and ARORIDE can add more than five kilometers per second of delta-V to 100 kg and 500 kg. kilogram of payload, respectively.
The Momentus Space Ride family could be the first step in changing the paradigm of satellite launching by providing more efficient space transportation than the top stages of launchers. In the future, the role of launchers could be limited to sending payloads into Earth orbit, where more efficient and reusable space-based transfer stages carry payloads to their destination. final.
Figure 3. Momentus Space is the first company to offer space tug transport services. |
United Launch Alliance Advanced Cryogenic Advanced Stage (ULA ACES) is an upper stage for their new Vulcan launch vehicle. ACES is designed for extended missions and refueling. The stage uses liquid oxygen and liquid hydrogen for propellers with a capacity of 68 tons. ACES can send payloads into geosynchronous orbit or around the Moon and return to low Earth orbit to refuel. ULA is currently developing the Vulcan Centaur with a first launch expected in 2021. The planned launch date for ACES Vulcan is in the mid-2020s (Figure 4).
Atomos Space is developing another low-thrust, high-impulse space tug for satellite operators. Atomos solves the last mile problem in space by providing an in-space transportation service that reduces launch costs for satellite operators.
Figure 4. ULA is developing a cryogenic upper stage with long life and can be refueled for its Vulcan launcher. |
| Space tugs are almost here today, thanks to Momentus Space. Reusable space tugs arrive. |
Interglobal is currently defining space tugs providing intra-orbital transport services in support of the ISS and future commercial space stations. Interglobal sees great potential for traveling between space stations in the same orbit. The intra-orbital transport architecture includes modular transfer vehicles, pressure modules and other elements. Interglobal can provide emergency transportation from one station to another instead of bringing the crew back to Earth. Interglobal space tugs may also transport products from manufacturing stations to orbital storage facilities for storage until a cargo return vehicle is available or filled to full capacity for return to Earth. This avoids the manufacturing facilities having to include a volume of product storage. A supply depot, or general store, with spare parts, consumables and other miscellaneous items may constitute a common logistic depot at several space stations.
Figure 5. Cislunar Space Development Company develops reusable LOx / LH space tugs for transport in the outer space. |
The space tugs of the Cislunar Space Development Corporation (CSDC) operate between a low earth orbit and a geo-synchronous transfer orbit (GTO), GEO and Lagrange Earth-Moon point 1 (Figure 5). The CSDC's space tugs capture customer satellites from a delivery orbit at an altitude of 185 kilometers or more, in the two degrees of inclination of their parking orbit. The maximum payload for GTC and GEO space tugs in the CSDC is four tonnes; The payload capacity of the CSDC EML1 tug is 25 tonnes. In-orbit refueling from ground-orbit propellant transporters or reusable LEO thruster repositories takes place prior to each mission.
Space tugs are almost here today, thanks to Momentus Space. Reusable space tugs arrive. They can come from Atomos, ULA, CSDC or from an unknown player. There will likely be low thrust and high thrust systems and low thrust systems, operating around and between the bodies of our solar system to meet the needs of various customers. Space tugs can relegate launch vehicles to simply placing payloads into Earth orbit.
Commercial lunar access for payloads and people
For the purposes of this document, lunar landers are single-use, disposable vehicles that deliver payloads to the Moon's surface and may house them. Moon shuttles are reusable round-trip vehicles that carry the payload to the surface, then return to their parking spot near the moon or carry men around. The lunar shuttles may or may not accommodate payloads on the surface of the moon. Many types of commercial lunar landers and lunar shuttles are currently in use, including: former Google Lunar X (GLXP) competition winners, NASA lunar payload service (CLPS) winners, NASA's large agency NASA Human Landing System, coming NASA Ascent Element BAA, and purely commercial approaches.
Former competitors of the Google Lunar X Award
The Google Lunar X Award, created in 2007, had a $ 30 million purse. Google canceled the price in 2018; The original deadline was in 2014. Twenty-nine teams registered for the award. 26 teams from 10 different countries plus three international teams. Finally, there were five finalists: Hakuto (Japan), Moon Express (United States), Team Indus (India), SpaceIL (Israel) and Synergy Moon (international). SpaceIL, launched in April 2019, reached lunar orbit but suffered an engine failure during the descent. The scientists Astrobotic, iSpace (Hakuto), Moon Express and PT are continuing their commercial lunar landing projects (Figure 6).
Figure 6. Lunar lander concepts of the five finalists of the Google Lunar X. |
Winners of NASA's Commercial Lunar Payload Services
In November 2018, NASA awarded nine companies unlimited quantity contracts with a combined maximum value of $ 2.6 billion over ten years for the delivery of a lunar payload. The companies are: Astrobotic (Pittsburgh), Deep Space Systems (Littleton, Colorado), Draper (Cambridge, Massachusetts), Firefly Aerospace (Cedar Park, Texas), Intuitive Machines (Houston), Lockheed Martin (Littleton, Colorado), Masten ( Mojave, California), Moon Express (Cape Canaveral, Florida) and OrbitBeyond (Edison, New Jersey). The payload capacity varies from 35 to 500 kilograms (Figure 7). Each company received an unspecified amount of funding to develop its Payload Utilization Guide.
Figure 7. Lander Concepts for Nine Winners of the NASA Commercial Lunar Payload Payload Services Opportunity. |
On May 31, NASA awarded $ 273.5 million for the first three moon delivery service contracts to Astrobotic, Intuitive Machines and OrbitBeyond. Astrobotic received $ 79.5 million in July 2021 for his proposal to haul up to 14 payloads until Lacus Mortis, a large crater located near the Moon. a dark spot scientifically intriguing on the Moon, by July 2021. Granting $ 97 million from Orbit Beyond will carry a maximum of four payloads to Mare Imbrium, a lava plain located in one of the craters by the end of September 2020. Unfortunately, OrbitBeyond had to withdraw their contract with NASA on July 29 because they could not meet planned milestones due to internal conflicts.
BAA Recipients of NASA's Human Landing System
Following the order given by the Trump administration to NASA to return humans to the moon before traveling to Mars, NASA has published its NextSTEP 2 BAA Appendix E: Human Landing System February 7th. Annex E defines NASA's reference human landing system architecture, comprising a descent element, transfer vehicle element, fueling element, climbing element and airframe element. surface combination. Proposals were to include concept studies and prototypes of descent, transfer vehicle and refueling elements for a human lunar landing in 2028 (Figure 8).
Figure 8. Theoretical Concepts of the Reference Architecture of the NASA Human Landing System. |
The proposing companies were to be able to develop their proposed systems and contribute at least 20% (large companies) or 10% (small companies) of the proposed price, with 50% of the contribution provided during the period of time. six-month study. The maximum value of the grant has been set at $ 9 million, with the majority of the funds allocated to the Descent component. On May 16, NASA awarded a total of $ 45.4 million to 11 companies:
- Aerojet Rocketdyne – Canoga Park, California
- Blue Origin – Kent, Washington
- Boeing – Houston
- Dynetics – Huntsville, Alabama
- Lockheed Martin – Littleton, Colorado
- Masten Space Systems – Mojave, California
- Northrop Grumman Innovation Systems – Dulles, Virginia
- OrbitBeyond – Edison, New Jersey
- Sierra Nevada Corporation, Louisville, Colorado, and Madison, Wisconsin
- SpaceX – Hawthorne, California
- SSL – Palo Alto, California
These rewarded efforts, scheduled to begin in July 2019, could lead to public-private partnership awards similar to those of commercial freight and the ISS crew. NASA and the selected companies will finance the development costs, followed by a service contract award with attribution to one or more companies.
Two companies presented their descent items to the public: Blue Origin and Lockheed Martin (Figure 9). For the first time, Blue Origin publicly unveiled its Blue Moon consumable item in March 2017. On May 9, Jeff Bezos unveiled a life-size mock-up at the Satellite 2019 conference. Blue Moon uses liquid oxygen and oxygen. liquid hydrogen for propellers and has a payload capacity of 3.6 tons. A stretched version could land 6.5 tons. Blue Moon is similar to a platform truck whose payload rests on the upper surface. Lockheed Martin presented his lunar landing in two stages at the 2019 Space Symposium in Colorado Springs, Colorado.
NASA Ascent Element BAA opportunity
On March 26, in the aftermath of Human Lander's BAA bid submission, the Trump Administration, via Vice President Pence's speech at NASA's Marshall Space Flight Center, doubled the decision to place American astronauts on the Moon before going on Mars asking for the human landing must take place before the end of the year 2024. NASA reacted to the challenge of issuing an update of its synopsis of pre-solicitation of climb element from April 8th to April 26th. NASA had planned the publication of Annex H by the end of May. E are likely to submit proposals for Appendix H, among others.
Figure 9. Two descent phase concepts aligned with the reference architecture of the NASA human landing system. |
NASA released the July 19 draft of Annex H, entitled Human Landing Integrated Lander System, and hosted a virtual industry forum on July 22. Although NASA's reference architecture to access the Moon includes a transfer vehicle component, a descent element and a climb element, bidders can: propose alternative solutions (Figure 10) . Options include a two-step approach using a descent element and a climb element, a one-step concept operating a round trip between Gateway and the lunar surface with or without an integrated crew module. NASA will not take ownership of the proposed integrated Lander. Rather, it is a public-private partnership in which bidders contribute up to 10% of the proposed development costs, then launch bids for future lunar landing missions as a commercial service.
Figure 10. NASA Gateway, Orion and Lunar Landing System Concept for the 2024 Human Lunar Mission: NASA |
Future Moon Shuttles
Lunar shuttles differ from the descent elements and climb elements identified by NASA by being round-trip vehicles between a near moon-crossing point and the lunar surface. Two companies publicly discussed the Moon's shuttles: Lockheed Martin and CSDC (Figure 11).
| Access to the moon, whether for scientific or technological payloads or for human beings, has moved away from NASA-owned spacecraft to become commercial companies selling attractions to NASA. |
Lockheed Martin presented his moon shuttle concept at the 2018 International Astronautical Congress in Bremen, Germany. Lockheed Martin's Moon shuttle sends four crewmembers and a ton of payload to the moon for a two-week stay. It does not require surface maintenance or refueling before returning to the bridge. The vehicle provides a total delta-V of five kilometers per second using liquid oxygen and liquid hydrogen as propellants with a specific pulse of 450 seconds. Lockheed Martin states that the vehicle's mass is 62 tons when it is loaded with propellant and 22 tons when it is empty.
Figure 11. Two concepts of lunar lander, or shuttle in the moon, that can be reused; one with an integrated crew module and the other after unloading a payload, which could be a crew module. |
The CSDC Moon shuttle is designed to carry 25 tonnes of EML1 to the moon's surface and return without payload without refueling. Delta-V is 2,520 meters per second in each direction. The propellant combination is liquid oxygen and liquid hydrogen with a specific pulse of 450 seconds. The CSDC's lunar shuttle propulsion capacity is between 49 and 69 tonnes and its dry weight is between 9 and 16 tonnes, depending on the assumed design margins. The CSDC Moon shuttle can carry up to 13 tons return between EML1 and the lunar surface.
Access to the moon, whether for scientific or technological payloads or for human beings, has moved away from NASA-owned spacecraft to become commercial companies selling attractions to NASA. Nine companies are currently eligible to offer lunar payload delivery services to NASA and NASA has awarded delivery contracts to three companies for the solicitation of commercial lunar payload services. NASA's NextSTEP BAA System: Appendix H, Integrated Human Landing System, calls on companies to develop human lunar surface access systems from Gateway. Companies must contribute up to 10% of the proposed development costs in exchange for maintaining ownership and the ability to compete for future missions. Reuse requirements (five uses) and mission opportunities (five to ten years) may be insufficient for a robust commercial transport service to the moon.
Support infrastructure
Transport architectures need supportive infrastructure. Motor vehicles need roads, service stations, service shops and tires, among others. Railways need runways, fuel depots, power lines and switching garages. Ships need tugs, loading docks and fuel sources. River transport requires tugs, barges, canals, loading docks and fuel depots. Similarly, commercial space transportation requires mooring facilities, tankers, propellant depots, personnel modules and propellant tankers (Figure 12).
Figure 12. Infrastructure is important in transportation networks; the gateway is the NASA node between space systems and lunar landers, while the CSDC thruster deposits are the nodes between Earth-to-Orbit, space-space and lunar landing systems. |
| For truly sustainable, operational and efficient transport between the Earth and the Moon, an integrated cislun transport architecture is needed, separating Earth-orbit launch, orbit transfer and lunar surface access, using vehicles in the space and reusable propellant depots. in low Earth orbit and near the moon. |
The Gateway is NASA's support infrastructure for the Moon and Mars missions. Its initial components include a power and propulsion element and a residential element. Gateway provides docking ports for Orion, a human landing system and a logistics module in its initial configuration. Gateway is a transport node where people and goods are transferred between Earth vehicles (Orion modules and logistics) and a human landing system, which operates between Gateway and the Moon. NASA is currently preparing a call for tenders for Gateway's logistics services to provide Gateway with supplies similar to ISS's commercial transport service contracts. The last RFP for this effort was released on August 16th.
Cislunar Space Development Company has defined another infrastructure to support its space tugs and moon shuttles. The tankers in Earth orbit provide liquid oxygen and liquid hydrogen to the GTO and GEO space tugs for just – in – time refueling, or water to the LEO thruster depots. The propellant deposits in LEO and EML1 produce liquid oxygen and liquid hydrogen from water and provide docking facilities for space tugs and shuttles from the Moon between missions. Space tugs transport liquid oxygen and hydrogen or liquid water tank trucks from LEO to EML1, and Moon shuttles deliver EML1 tankers from the moon. The personnel modules are payloads of space tugs and lunar shuttles for human exploration and space tourism missions from LEO to Moon and intermediate points.
Closing thoughts
Commercial space transportation now includes launch services and freight delivery to the International Space Station. In addition, two companies posted prices for commercial space transportation services; one to the Moon and one to higher orbits of the International Space Station or launch vehicle launch points. Soon, there will be commercial rides available for adventure travelers and astronauts on suborbital flights and to the ISS. According to NASA's integrated BAA landing system, by 2024, transport between Gateway and the Moon will be a commercial service. Several companies are developing commercial transport concepts in urban space and throughout the solar system. However, for transport between the Earth and the Moon to be truly sustainable, exploitable and efficient, an integrated cislunar transport architecture is needed. According to the CSDC, an integrated cununary transport architecture is an architecture that separates ground launch, orbit transfer and access to the lunar surface, using vehicles in the area. Reusable space and deposits of thrusters in low Earth orbit and near the Moon. The architecture uses liquid oxygen and liquid hydrogen produced from water launched by the Earth until water is economically available on the ground. Moon. Hang on to your helmet as a commercial space transportation medium for satellites, logistics and people are about to reach the exit speed.
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