Lunar Gateway of NASA's Artemis Program
As reflected in NASA's Exploration Campaign, the next step in human spaceflight is the establishment of U.S. preeminence in cislunar space through the operations and the deployment of a U.S.-led Lunar Orbital Platform-Gateway. Together with the Space Launch System (SLS) and Orion, the gateway is central to advancing and sustaining human space exploration goals, and is the unifying single stepping off point in our architecture for human cislunar operations, lunar surface access and missions to Mars. The gateway is necessary to achieving the ambitious exploration campaign goals set forth by Space Policy Directive 1. Through partnerships both domestic and international, NASA will bring innovation and new approaches to the advancement of these U.S. human spaceflight goals. 1) 2)
As NASA sets its sights on returning to the Moon, and preparing for Mars, the agency is developing new opportunities in lunar orbit to provide the foundation for human exploration deeper into the solar system. For months, the agency has been studying an orbital outpost concept in the vicinity of the Moon with U.S. industry and the International Space Station partners. As part of the fiscal year 2019 budget proposal, NASA is planning to build the Lunar Orbital Platform-Gateway in the 2020s.
The platform will consist of at least a power and propulsion element and habitation, logistics and airlock capabilities. While specific technical and mission capabilities as well as partnership opportunities are under consideration, NASA plans to launch elements of the gateway on the agency’s Space Launch System or commercial rockets for assembly in space.
“The Lunar Orbital Platform-Gateway (formerly known as the Deep Space Gateway) will give us a strategic presence in cislunar space. It will drive our activity with commercial and international partners and help us explore the Moon and its resources,” said William Gerstenmaier, associate administrator, Human Exploration and Operations Mission Directorate, at NASA Headquarters in Washington. “We will ultimately translate that experience toward human missions to Mars.”
The power and propulsion element will be the initial component of the gateway, and is targeted to launch in 2022. Using advanced high-power solar electric propulsion, the element will maintain the gateway’s position and can move the gateway between lunar orbits over its lifetime to maximize science and exploration operations. As part of the agency’s public-private partnership work under Next Space Technologies for Exploration Partnerships, or NextSTEP, five companies are completing four-month studies on affordable ways to develop the power and propulsion element. NASA will leverage capabilities and plans of commercial satellite companies to build the next generation of all electric spacecraft.
The power and propulsion element will also provide high-rate and reliable communications for the gateway including space-to-Earth and space-to-lunar uplinks and downlinks, spacecraft-to-spacecraft crosslinks, and support for spacewalk communications. Finally, it also can accommodate an optical communications demonstration – using lasers to transfer large data packages at faster rates than traditional radio frequency systems.
Habitation capabilities launching in 2024 will further enhance our abilities for science, exploration, and partner (commercial and international) use. The gateway’s habitation capabilities will be informed by NextSTEP partnerships, and also by studies with the International Space Station partners. With this capability, crew aboard the gateway could live and work in deep space for up to 30 to 60 days at a time.
Crew will also participate in a variety of deep space exploration and commercial activities in the vicinity of the Moon, including possible missions to the lunar surface. NASA also wants to leverage the gateway for scientific investigations near and on the Moon. The agency recently completed a call for abstracts from the global science community, and is hosting a workshop in late February to discuss the unique scientific research the gateway could enable. NASA anticipates the gateway will also support the technology maturation and development of operating concepts needed for missions beyond the Earth and Moon system.
Adding an airlock to the gateway in the future will enable crew to conduct spacewalks, enable science activities and accommodate docking of future elements. NASA is also planning to launch at least one logistics module to the gateway, which will enable cargo resupply deliveries, additional scientific research and technology demonstrations and commercial use.
Following the commercial model the agency pioneered in low-Earth orbit for space station resupply, NASA plans to resupply the gateway through commercial cargo missions. Visiting cargo spacecraft could remotely dock to the gateway between crewed missions.
Drawing on the interests and capabilities of industry and international partners, NASA will develop progressively complex robotic missions to the surface of the Moon with scientific and exploration objectives in advance of a human return. NASA’s exploration missions and partnerships will also support the missions that will take humans farther into the solar system than ever before.
NASA’s Space Launch System rocket and Orion spacecraft are the backbone of the agency’s future in deep space. Momentum continues toward the first integrated launch of the system around the Moon in fiscal year 2020 and a mission with crew by 2023. The agency is also looking at a number of possible public/private partnerships in areas including in-space manufacturing and technologies to extract and process resources from the Moon and Mars, known as in-situ resource utilization.
Figure 1: NASA’s Lunar Outpost will Extend Human Presence in Deep Space (image credit: NASA)
NASA wants to understand how U.S. industry would use or enhance the Gateway to support a growing space economy. The agency issued a Request for Information (RFI) June 18, 2018, to determine interest in technical solutions to meet exploration goals and possible contract or partnership interest to advance private sector demand. 3)
The Gateway will serve as the staging area for the agency’s next phase of exploration, and will open up human and robotic exploration and breakthrough science on the Moon, and in deep space. It has unique characteristics and capabilities that may be of use to private companies for commercial applications.
“As we return to the Moon and push human exploration farther into the solar system, we want to expand our partnerships from low-Earth orbit to deep space,” said Phil McAlister, director of Commercial Spaceflight Development at NASA Headquarters in Washington. “We believe partnering with U.S. industry to maximize the commercial utility of the Gateway will help enhance the economic development of space.”
Results from the RFI will help inform NASA’s development for Gateway requirements. For example, NASA is interested in understanding how moving the Gateway between orbits in the vicinity of the Moon may impact potential uses. Helping expand the commercial space business and seeking ideas from U.S. companies to support it keeps NASA apprised on developing external technologies and can guide the agency’s future exploration.
Among other topics, NASA wants to hear from industry regarding potential frequency of visits to the Gateway; plans on how they would obtain crew or cargo transportation; resource requirements such as power and communications; and any potential barriers to commercial use of the Gateway.
NASA’s return to the Moon with commercial and international partners is part of an overall agency Exploration Campaign in support of Space Policy Directive 1. New Commercial Lunar Payload Services or CLPS delivery missions will be among the first robotic steps back on the Moon, beginning as early as 2019. NASA will follow these early, small lander missions with the first of two larger lander demonstration missions planned in 2022. These larger lander missions will be an important step toward evolution to human landers, and are expected to be built through public/private partnerships.
NASA plans to conduct more research on the Moon’s surface ahead of a human return. And that long-term exploration and development of the Moon will give NASA experience for the next giant leap – missions deeper into the solar system, including Mars.
Status of the Gateway Study and Development phases
• March 30, 2020: NASA has selected SpaceX of Hawthorne, California, as the first U.S. commercial provider under the Gateway Logistics Services contract to deliver cargo, experiments and other supplies to the agency's Gateway in lunar orbit. The award is a significant step forward for NASA's Artemis program that will land the first woman and next man on the Moon by 2024 and build a sustainable human lunar presence. 4) 5)
- At the Moon, NASA and its partners will gain the experience necessary to mount a historic human mission to Mars.
- SpaceX will deliver critical pressurized and unpressurized cargo, science experiments and supplies to the Gateway, such as sample collection materials and other items the crew may need on the Gateway and during their expeditions on the lunar surface.
- "This contract award is another critical piece of our plan to return to the Moon sustainably," said NASA Administrator Jim Bridenstine. "The Gateway is the cornerstone of the long-term Artemis architecture and this deep space commercial cargo capability integrates yet another American industry partner into our plans for human exploration at the Moon in preparation for a future mission to Mars."
- NASA is planning multiple supply missions in which the cargo spacecraft will stay at the Gateway for six to 12 months at a time. These firm-fixed price, indefinite delivery/indefinite quantity contracts for logistics services guarantee two missions per logistics services provider with a maximum total value of $7 billion across all contracts as additional missions are needed.
- "Returning to the Moon and supporting future space exploration requires affordable delivery of significant amounts of cargo," said SpaceX President and Chief Operating Officer Gwynne Shotwell. "Through our partnership with NASA, SpaceX has been delivering scientific research and critical supplies to the International Space Station since 2012, and we are honored to continue the work beyond Earth's orbit and carry Artemis cargo to Gateway."
- NASA issued a call for proposals for the Gateway Logistics Services program in August. Companies had to propose spacecraft capable of carrying at least 3,400 kg of pressurized cargo and 1,000 kg of unpressurized cargo to the Gateway, and be able to dispose of at least as much cargo from the Gateway. Proposals were due in October and NASA originally expected to make awards by the end of 2019. The agency didn’t disclose the reason for the nearly three-month delay.
Figure 2: SpaceX's Dragon XL, seen here separating from the upper stage of its Falcon Heavy rocket, will deliver cargo to the lunar Gateway under a NASA contract awarded March 27 (image credit: SpaceX)
- Each mission will remain docked to the station for up to a year and could provide additional volume for crews there. “Bringing a logistics provider onboard ensures we can transport all the critical supplies we need for the Gateway and on the lunar surface to do research and technology demonstrations in space that we can’t do anywhere else. We also anticipate performing a variety of research on and within the logistics module,” said Dan Hartman, the Gateway program manager NASA’s Johnson Space Center, in the statement.
- The Gateway Logistics Services contract enables NASA to order missions for as long as 12 years with a 15-year performance period and provides the ability to add new competitive providers.
- These missions will support NASA's plans for sustainable exploration with both international and commercial partners, while developing the experience and capabilities necessary to send humans to Mars.
- "This is an exciting new chapter for human exploration," said Mark Wiese, Deep Space Logistics manager at NASA's Kennedy Space Center in Florida. "We are bringing the innovative thinking of commercial industry into our supply chain and helping ensure we're able to support crews preparing for lunar surface expeditions by delivering the supplies they need ahead of time."
- Charged with returning to the Moon in the next four years, NASA's Artemis program will reveal new knowledge about the Moon, Earth and our origins in the solar system. The Gateway is a vital part of NASA's deep space exploration plans, along with the Space Launch System (SLS) rocket, Orion spacecraft, and human landing system that will send astronauts the Moon.
- One standard logistics service mission is anticipated for each Artemis SLS/Orion crewed mission to the Gateway. Gaining new experiences on and around the Moon will prepare NASA to send the first humans to Mars in the coming years, and the Gateway will play a vital role in this process.
- "We're making significant progress moving from our concept of the Gateway to reality," said Dan Hartman, Gateway program manager at NASA's Johnson Space Center in Houston.
- "Bringing a logistics provider onboard ensures we can transport all the critical supplies we need for the Gateway and on the lunar surface to do research and technology demonstrations in space that we can't do anywhere else. We also anticipate performing a variety of research on and within the logistics module."
• March 13, 2020: The first science experiments that will be hosted on the Gateway, an international outpost which will orbit the Moon, have been selected by ESA and NASA. Europe’s contribution will monitor radiation to gain a complete understanding of cosmic and solar rays in unexplored areas as the orbital outpost is assembled around the Moon. 6)
- The first module for the Gateway, the Power and Propulsion Element, is set to host two external scientific investigations.
- ESA’s hardware will actively monitor radiation at all times and return data for scientists from participating countries to consult.
- As the Gateway module flies to its position in a halo-like orbit around the Moon, it will pass through the Van Allen radiation belt – an area around Earth where high-energy particles are trapped by our planet’s magnetic field. The particles can cause more radiation damage to humans, and the hardware will provide useful information on to how to keep astronauts safe as they pass through the belt.
- Once in position, the Gateway will orbit the Moon flying as close as 3,000 km from the lunar surface and at its furthest, 70,000 km. The radiation investigation will continue to monitor the changes in protons, electrons and heavy ions and neutrons as they hit the measuring instruments.
- Mission planners at NASA and ESA’s Space Operations Center (ESOC) have spent months debating the pros and cons of different orbits, and have now decided on the path of the lunar Gateway – a ‘near-rectilinear halo orbit’, or NRHO. — Instead of orbiting around the Moon in a low lunar orbit like Apollo, the Gateway will follow a highly ‘eccentric’ path. At is closest, it will pass 3,000 thousand km from the lunar surface and at its furthest, at 70,000 km. The orbit will actually rotate together with the moon, and as seen from the Earth will appear a little like a lunar halo.
Figure 3: Mission planners at NASA and ESA’s Space Operations Center (ESOC) have spent months debating the pros and cons of different orbits, and have now decided on the path of the lunar Gateway – a ‘near-rectilinear halo orbit’, or NRHO. — Instead of orbiting around the Moon in a low lunar orbit like Apollo, the Gateway will follow a highly ‘eccentric’ path. At is closest, it will pass 3,000 km from the lunar surface and at its furthest, at 70,000 km. The orbit will actually rotate together with the moon, and as seen from the Earth will appear a little like a lunar halo. — A permanent base in this orbit around the Moon will act as a staging post, from where parts can be left behind, picked up and assembled. After liftoff, only a moderate maneuver will be needed to slow a visiting spacecraft to rendezvous with the Gateway (video credit: ESA)
Heavy interactions in space
- “Heavy neutrons are of particular interest for us,” says ESA’s Science Team Leader of Human and Robotic Exploration Jennifer Ngo-Anh “some cosmic rays hit the Moon and interact with the surface to reflect as heavy neutrons that are particularly damaging to humans. We need to know more about where and how these particles form, to protect astronauts.”
- NASA’s first investigation to fly aboard the Gateway is a Sun-oriented space weather experiment to observe solar particles and solar wind. Large explosions on the Sun are unpredictable and can result in violent outbursts of radiation and energetic solar wind that could hit astronauts as they venture outside the protective atmosphere of Earth.
- “Both these experiments will work together to supply much-needed information to forecast radiation events and how to build better spacecraft and protection for astronauts on and around the Moon,” explains ESA’s director of Human and Robotic Exploration David Parker.
- “As we prepare for the next generation of European astronauts who will join their NASA colleagues in the Artemis program, this research is of vital importance and shows how science and exploration go hand-in-hand as we move forward to the Moon.”
- More science will be selected to fly aboard the Gateway in the future to take advantage of the unique environment in lunar orbit that cannot be duplicated on Earth or on the International Space Station.
- The Gateway will be built and assembled this decade as a platform for exploration, science, and commercial activities in deep space. Gateway operations will provide invaluable experience and demonstrate critical technologies in support of a future human mission to Mars. Following decisions at Space19+, ESA will build a Habitation module, communications systems and a refuelling module for the Gateway. The Canadian Space Agency (CSA) has committed to provide advanced robotics for the lunar outpost. The Japanese Aerospace Exploration Agency is also in discussion to supply elements.
• March 9, 2020: Humankind’s next space outpost, the lunar Gateway, will serve as a staging point to reach the surface of the Moon. A new ESA-backed study is considering whether it could also be used as a deployment point for planetary defense missions, to intercept asteroids approaching dangerously close to Earth. 7)
Figure 4: The Gateway, an Orion vehicle docked with the lunar outpost, is the next structure to be launched by the partners of the International Space Station. During the 2020s, Gateway will be assembled and operated in the vicinity of the Moon, where it will move between different orbits and enable the most distant human space missions ever attempted. Placed farther from Earth than the current Space Station the Gateway will offer a staging post for missions to the Moon and Mars. Its flight path is a highly-elliptical orbit around the Moon – bringing it both relatively close to the Moon’s surface but also far away making it easier to pick up astronauts and supplies from Earth – around a five-day trip. The Gateway will have a mass of ~ 40 tons and will consist of a service module, a communications module, a connecting module, an airlock for spacewalks, a place for the astronauts to live and an operations station to command the gateway’s robotic arm or rovers on the Moon. Astronauts will be able to occupy it for up to 90 days at a time (image credit: ESA)
- Set for assembly over the course of this decade, the Gateway will be placed in a highly elongated, or ‘eccentric’ week-long orbit around the Moon, passing a minimum 3,000 km from the lunar surface and 70,000 km at its furthest away. Crewed missions will require much less energy to rendezvous with the Gateway than to fly direct to the surface of the Moon, and could then venture down using Gateway-based landers.
- But the Gateway could also support operations into deep space – including spacecraft for planetary defense, to deflect the orbital paths of incoming asteroids.
- The concept might sound like science fiction, but Earth’s first planetary defense missions are already in active preparation. NASA’s Double Asteroid Redirect Test (DART) spacecraft, due to launch next year, will impact the smaller of the Didymos asteroid pair, in orbit between Earth and Mars, in a bid to shift its orbit. In 2026 ESA’s Hera spacecraft will perform a close-up survey of the asteroid post-impact.
- The DART and Hera missions, known jointly as the Asteroid Impact and Deflection Assessment (AIDA) collaboration represent an experimental trial-run on a distant body that poses no threat to Earth. Once proven, the deflection technique could be used for real on asteroids coming dangerously close – but a rapid reaction time would be crucial for maximum effectiveness.
- Accordingly ESA is funding a new study by Politechnico di Milano to analyze options for using the Gateway to park planetary defense spacecraft in readiness to intercept incoming asteroids. These spacecraft would be able to depart the Gateway with much lower energies compared with departing from Earth itself.
- “This promising study comes out of one of the latest ideas received through ESA’s Open Space Innovation Platform, OSIP,” explains Moritz Fontaine, the Agency’s Discovery and Preparation Officer. “Using OSIP, anyone is welcome to propose novel ideas to address space-related challenges.
- “We channel the most promising ideas through appropriate ESA implementation paths. Ideas can come from anyone: specialist researchers, companies or members of the public. Although OSIP was launched less than a year ago, we have already received hundreds of proposals.”
- Other OSIP-submitted research ideas selected for funding in January 2020 include:
a) New ways of building satellites might be creating a new type of space debris: the latest carbon fibre reinforced plastics, when broken apart, could be giving rise to vast amounts of tiny fragments of carbon fibres. These are not represented in current debris models, so a dedicated model needs to be made.
b) Air-filled integrated waveguides could enable the design of low-cost, high performance antennas for the coming wave of satellite constellations.
c) The autonomy of embedded devices aboard satellites could be boosted using AI-based hardware accelerators.
d) With nanomaterials used increasingly for biomedical applications, investigation is needed into how weightlessness influences their effects within biological systems.
• November 1, 2019: Ambitious projects are underway in preparation for the upcoming ARTEMIS Mission challenge in 2024. Two companies, space supplier RUAG Space and high-tech company TTTech are offering high-performance data exchange electronics for Lunar Gateway modules – in time for the ARTEMIS Mission challenge in 2024. 8)
- In 2011, via a Space Act Agreement, TTTech and NASA standardized TTEthernet technology as an open industry standard i.e. SAE AS6802 together with several industry partners. This open standard has recently been ratified by NASA, ESA, CSA and JAXA as the IASIS (International Avionics System Interoperability Standards) for deep space applications.
- TTEthernet technology allows fast and reliable data transfer on the “Lunar Gateway” space station, which will orbit around the Moon and serve as the portal to the surfaces of Moon and Mars. RUAG Space will provide space qualified hardware that enables the use of this highly reliable technology in space applications. Both companies will offer these electronic products to all interested customers. TTEthernet is also used very successfully by the NASA Orion spacecraft and by the new European launcher Ariane 6 as the on-board avionics backbone network.
- Peter Guggenbach, CEO RUAG Space said that this is a perfect partnership. An electronic product that brings together the strong experience from RUAG in space hardware engineering and manufacturing with the expertise in software and ASICs from TTTech. They have invested a lot of resources into engineering and customers can trust them to bring a reliable product that is ready-to-use. With their legacy of success, they will help customers save time and meet their ambitious mission schedules. The first crewed mission i.e. ARTEMIS to the “Lunar Gateway” station and the moon is planned for 2024.
Figure 5: Time-Triggered Ethernet is faster and more reliable than any other technology in the market. Pictured: TTEthernet platform for outer space (image credit: TTTech)
- Christian Fidi, VP Products, Sales and Marketing of TTTech’s Aerospace business unit, highlights the safety and reliability of the technological solutions added that they have delivered a safety-critical standard that is proven and as yet unmatched in the industry. Customers benefit from off-the-shelf hardware solutions that perfectly serve a highly competitive and dynamic space market. Time-Triggered Ethernet is faster and more reliable than any other technology in the market.
- Time-Triggered Technology was invented by TTTech. The company describes the essence of this technology is to create networks that are fully deterministic, meaning each sender and receiver in a network knows when to send or expect a message. This brings several advantages: Not only are all failures that result in some latency in the network eliminated, it also allows to use the entire bandwidth of the links within the networks.
- These interfaces will permit Canadarm3 to attach and operate on the exterior of the Gateway modules.
- The first contract is awarded to MDA (MacDonald, Dettwiler and Associates), a Maxar company. The contract covers concept and technology development activities of robotics interfaces for the XLA (eXploration Large Arm).
- The second contract is also awarded to MDA, a Maxar company. The contract covers concept and technology development activities of robotics interfaces for the smaller XDA (eXxploration Dexterous Arm).
• July 18, 2019: Mission planners at NASA and ESA/ESOC (European Space Operations Center) have spent months debating the pros and cons of different orbits, and have now decided on the path of the lunar Gateway - called the angelic halo orbit or the NRHO (Near-Rectilinear Halo Orbit). 10)
- Like the International Space Station, the Gateway will be a permanent and changeable human outpost. Instead of circling our planet, however, it will orbit the Moon, acting as a base for astronauts and robots exploring the lunar surface.
- Like a mountain refuge, it will also provide shelter and a place to stock up on supplies for astronauts en route to more distant destinations, as well as providing a place to relay communications and a laboratory for scientific research.
- Mission analysis teams at ESOC are continuing to work closely with international partners to understand how this choice of orbit affects vital aspects of the mission – including landing, rendezvous with future spacecraft and contingency scenarios needed to keep people and infrastructure safe.
Figure 6: Angelic halo orbit chosen for humankind’s first lunar outpost (video credit: ESA)
- Instead of orbiting around the Moon in a low lunar orbit like Apollo, the Gateway will follow a highly ‘eccentric’ path. At is closest, it will pass 3,000 km from the lunar surface and at its furthest, at 70,000 km. The orbit will actually rotate together with the moon, and as seen from the Earth will appear a little like a lunar halo.
- A permanent base in this orbit around the Moon will act as a staging post, from where parts can be left behind, picked up and assembled. After liftoff, only a moderate maneuver will be needed to slow a visiting spacecraft to rendezvous with the Gateway.
- Orbits like these are possible because of the interplay between the Earth and Moon’s gravitational forces. As the two large bodies dance through space, a smaller object can be ‘caught’ in a variety of stable or near-stable positions in relation to the orbiting masses, also known as libration or Lagrange points.
- Such locations are perfect for planning long-term missions, and to some extent dictate the design of the spacecraft, what it can carry to and from orbit, and how much energy it needs to get – and stay – there.
- Travelling on the NRHO path, one revolution of the Gateway in its orbit about the Moon would take approximately seven days. This period was chosen to limit the number of eclipses, when the gateway would be shrouded by the Earth's or the Moon’s shadow.
- “Finding a lunar orbit for the gateway is no trivial thing.” says Markus Landgraf, Architecture Analyst working with ESA’s Human and Robotic Exploration activities. “If you want to stay there for several years, the near rectilinear halo orbit is slightly unstable and objects in this orbit do have a tendency of drifting away”. To keep the Gateway in position, regular small station-keeping maneuvers will be required.
Take the stage
- So why this orbit? The fundamental limiting factor when moving parts from Earth, to a potential lunar base and the Moon’s surface, is energy.
- “In human spaceflight we don’t fly one single, monolithic spacecraft,” explains Florian Renk, Mission Analyst in ESOC’s Flight Dynamics Division. “Instead we fly bits and pieces, putting parts together in space and soon on the surface of the Moon. Some parts we leave behind, some we bring back – the structures are forever evolving.”
- To escape Earth’s gravitational pull requires a huge amount of energy. To then land on the Moon and not hurtle straight past it, we have to slow down by losing that same energy. We can save some of this energy by leaving parts of the spacecraft in orbit, taking only what we need to the surface of the Moon.
- A permanent base in this orbit around the Moon will act as a staging post, from where parts can be left behind, picked up and assembled. After liftoff, only a moderate maneuver will be needed to slow a visiting spacecraft to rendezvous with the Gateway.
- The Lunar lander will then transport people, robots and infrastructure down to the surface when the Gateway is closest to the Moon, which happens about every seven days. Likewise, a transfer window to the gateway opens about every seven days for the return trip from the lunar surface.
Figure 7: The space Gateway is the next structure to be launched by the partners of the International Space Station. During the 2020s, it will be assembled and operated in the vicinity of the Moon, where it will move between different orbits and enable the most distant human space missions ever attempted. Placed farther from Earth than the current Space Station – but not in a lunar orbit – the Gateway will offer a staging post for missions to the Moon and Mars. Like a mountain refuge, it will provide shelter and a place to stock up on supplies for astronauts en route to more distant destinations. It will also offer a place to relay communications and can act as a base for scientific research.- The Gateway will have a mass of around 40 tons and will consist of a service module, a communications module, a connecting module, an airlock for spacewalks, a place for the astronauts to live and an operations station to command the gateway’s robotic arm or rovers on the Moon. Astronauts will be able to occupy it for up to 90 days at a time (image credit: NASA/ESA)
• June 14, 2019: In the latest step in sending astronauts to the lunar surface within five years, NASA issued a draft solicitation June 14 to industry seeking comments for a future opportunity for American companies to deliver cargo and other supplies to the Gateway in lunar orbit. 11)
- The first logistics service to the orbital outpost is expected to deliver science, cargo and other supplies in support of the agency’s new Artemis lunar exploration program, which includes sending the first woman and the next man to the surface of the Moon by 2024.
- Last fall, NASA asked American companies for ideas on how to best supply the Gateway, which will be located in an orbit around the Moon about 250,000 miles from Earth. The Gateway will be a command and service module for missions to the lunar surface and eventually, exploration farther into the solar system. Following up on that initial request for information, today NASA published a draft solicitation for industry comments on its logistics approach, which are due July 10, 2019.
- “We’re asking industry to provide a spacecraft to deliver cargo and other supplies to the Gateway. It will dock to the orbital outpost, but will be responsible for generating its own power,” said Marshall Smith, director, human lunar exploration programs at NASA Headquarters in Washington. “We’re using the Moon as a proving ground for Mars to develop the technologies and systems we need for exploration farther into the solar system, so we look forward to seeing how industry responds to our upcoming solicitation, and potentially awarding multiple contracts for this lunar service.”
- This latest call is mirroring similar cargo resupply services the agency pioneered with industry closer to home. NASA led the way for commercialization of low-Earth orbit, and is now providing new opportunities for private companies in deep space.
- “The Gateway, and specifically our logistics supply requirements, enables the deep space supply chain, taking the next step toward further commercialization of space,” said Mark Wiese, NASA’s Gateway logistics element manager at Kennedy Space Center in Florida. “In addition to delivering cargo, science and other supplies to the Gateway with these services, there’s potential for an extension to industry to deliver other elements of our lunar architecture with this solicitation.”
- A formal solicitation for a firm-fixed price contract is expected this summer. NASA anticipates the maximum contract award for all Gateway services over the course of 15 years will be valued at $7 billion.
- NASA will host an industry day forum in Florida on June 26 to answer questions and explain the proposed approach for logistic deliveries. Additional details about that opportunity for industry are available online.
- This announcement comes on the heels of other recent agency efforts to accelerate its Moon to Mars exploration plans. At the end of May, NASA awarded a contract to Maxar Technologies to build, launch, and demonstrate in space the power and propulsion element of the Gateway. And ahead of sending astronauts to the Moon, the agency will use a series of commercial Moon deliveries to send a suite of science instruments and technology demonstrations to the surface to continue studying Earth’s nearest neighbor. NASA is also working with 11 companies to study the proposed architecture for a new integrated human landing system, which would be staged at the Gateway for missions to the lunar surface.
- Charged with returning to the Moon within five years, NASA’s lunar exploration plans are based on a two-phase approach: the first is focused on speed – landing on the Moon by 2024 – while the second will establish a sustained human presence on and around the Moon by 2028. The agency will use what we learn on the Moon to prepare for the next giant leap – sending astronauts to Mars.
• May 31, 2019: NASA has just announced a major step forward in its plan to send astronauts to the Moon by 2024: task order awards to three commercial partners to deliver NASA science and technology instruments to the Moon. This is one of many recent milestones to come in our new Artemis program to explore the Moon. 12)
- On April 9, NASA expressed its commitment to a timeline of landing humans on the lunar south pole by 2024, The agency’s lunar exploration plans are based on a two-phased approach: the first is focused on speed – landing astronauts on the Moon in five years – while the second will establish a sustained human presence on and around the Moon by 2028. NASA will use an orbiting lunar outpost called Gateway to access the Moon. The agency is targeting launch of the power and propulsion element in late 2022.
- Planning this program requires many different pieces, including new technologies and partnerships. Developments on all fronts are moving ahead rapidly. Here's a summary of recent progress with Artemis.
A Charge Forward
- The Artemis program will send the first woman and the next man to the Moon by 2024 and develop a sustainable human presence on the Moon by 2028. The program takes its name from the twin sister of Apollo and goddess of the Moon in Greek mythology.
- Our Moon to Mars exploration approach is outlined in Space Policy Directive-1, which President Trump signed into law in December 2017. In one of the first steps to accomplish this bold goal, NASA announced its CLPS (Commercial Lunar Payload Services) initiative, in which companies under contract can bid on delivering science and technology payloads to the Moon. These public-private partnerships will be essential to the development of Artemis program by helping us study the Moon ahead of a human return.
Astronaut Health Projects Selected
- Astronauts face a very different environment in space than on Earth, and scientists are still investigating the many possible impacts of spaceflight on the human body. On April 30, NASA selected 12 proposals for projects related to studying astronaut health and performance during future long-duration missions beyond low-Earth orbit. These include what effects stress and sleep disturbances in space may have on the brain function, as well as how the immune system responds to simulated microgravity.
- The 12 projects will help prepare astronauts for what they may experience on missions to the Moon, and eventually Mars.
- Sending humans to the Moon by 2024 will require funds specifically for this endeavor. On May 13, President Trump announced a budget amendment for fiscal year 2020 of $1.6 billion to put NASA on track to accomplish this feat.
New Technologies from Small Business
- A sustainable human presence on the Moon and sending astronauts to Mars will require a variety of new innovations. On May 14, NASA announced small business awards totaling $106 million that included technologies in the areas of human exploration and operations, space technology, science, and aeronautics. The awards green-lit 142 proposals from 129 U.S. small businesses.
- Many of these selected projects have direct applications to Artemis and other future human exploration endeavors. For example, the technology behind solar panels that deploy like venetian blinds can be used as a surface power source for crewed missions on the Moon and Mars.
Human Lander Prototypes
- NASA is planning to get astronauts to the lunar surface and back through a multi-part landing system. They will start on the Gateway orbiting lunar outpost and ride down to low-lunar orbit in a spacecraft called a "transfer element." Then, a different spacecraft called the "descent element" will take them down to the Moon's surface. An ascent element will take them back to the Gateway. NASA is investigating ways to make these systems reusable through refueling.
- On May 16, NASA selected 11 companies to advance technology to land humans on the Moon. The companies will conduct studies and build prototypes for the Artemis program. These projects will relate to the descent, transfer, and refueling elements of a potential human landing system.
Power and Propulsion Element
- The ambitious Gateway lunar outpost, which will enable access to more of the Moon than ever before, will need power, propulsion and communications capabilities. On May 23, NASA announced that Maxar Technologies, formerly SSL, in Westminster, Colorado, would develop and demonstrate these capabilities for the Gateway through a component called the "power and propulsion element."
- The power and propulsion element, the first element of the Gateway that will launch to lunar orbit, is a spacecraft itself. It will fly by means of a technology called solar electric propulsion, but with three times more powerful than what has flown so far. This power and propulsion element will provide communications relays, including for human and robotic landers as well as visiting vehicles. NASA is targeting a launch of this element no later December 2022.
Artemis 1, 2, and 3
- NASA Administrator Jim Bridenstine spoke about the Gateway element and Artemis in general on May 23 at the Florida Institute of Technology. He outlined that the Artemis 1 mission will send the first human spacecraft to the Moon in the 21st century through a test flight of the Space Launch System (SLS) rocket and Orion spacecraft as an integrated system. Artemis 2 will be the first flight of human crew to the Moon aboard this SLS-Orion system. And Artemis 3 will send the first crew to the lunar surface. 13)
- On May 31 as part of the CLPS initiative, NASA selected the first three commercial Moon landing service providers that will deliver science and technology payloads to the lunar surface. Representatives from each company explained their concepts in a televised event at NASA's Goddard Space Flight Center in Greenbelt, Maryland. These missions will acquire new science measurements and enable important technology demonstrations, whose data will inform the development of future landers and other exploration systems needed for astronauts to return to the Moon by 2024.
• May 23, 2019: In one of the first steps of the agency’s Artemis lunar exploration plans, NASA announced on Thursday the selection of Maxar Technologies, formerly SSL (Space Systems/Loral), in Westminster, Colorado, to develop and demonstrate power, propulsion and communications capabilities for NASA’s lunar Gateway. 14)
- “The power and propulsion element is the foundation of Gateway and a fine example of how partnerships with U.S. companies can help expedite NASA’s return to the Moon with the first woman and next man by 2024,” said NASA Administrator Jim Bridenstine. “It will be the key component upon which we will build our lunar Gateway outpost, the cornerstone of NASA’s sustainable and reusable Artemis exploration architecture on and around the Moon.”
- The power and propulsion element is a high-power, 50 kW solar electric propulsion spacecraft – three times more powerful than current capabilities. As a mobile command and service module, the Gateway provides a communications relay for human and robotic expeditions to the lunar surface, starting at the Moon’s South Pole.
- This firm-fixed price award includes an indefinite-delivery/indefinite-quantity portion and carries a maximum total value of $375 million. The contract begins with a 12-month base period of performance and is followed by a 26-month option, a 14-month option and two 12-month options.
- Spacecraft design will be completed during the base period, after which the exercise of options will provide for the development, launch, and in-space flight demonstration. The flight demonstration will last as long as one year, during which the spacecraft will be fully owned and operated by Maxar. Following a successful demonstration, NASA will have the option to acquire the spacecraft for use as the first element of the Gateway. NASA is targeting launch of the power and propulsion element on a commercial rocket in late 2022.
- “We’re excited to demonstrate our newest technology on the power and propulsion element. Solar electric propulsion is extremely efficient, making it perfect for the Gateway,” said Mike Barrett, power and propulsion element project manager at NASA’s Glenn Research Center in Cleveland. “This system requires much less propellant than traditional chemical systems, which will allow the Gateway to move more mass around the Moon, like a human landing system and large modules for living and working in orbit.”
- Charged with returning to the Moon within five years, NASA’s lunar exploration plans are based on a two-phase approach: the first is focused on speed – landing on the Moon by 2024 – while the second will establish a sustained human presence on and around the Moon by 2028. We then will use what we learn on the Moon to prepare to send astronauts to Mars.
Figure 8: The power and propulsion element of NASA's Gateway is a high-power, 50 kW solar electric propulsion spacecraft – three times more powerful than current capabilities (image credit: NASA)
Figure 9: NASA announces the first partnership of its kind with MAXAR Technologies to power the future lunar orbiting station (video credit: NASA, Published on May 23, 2019)
• May 13, 2019: NASA is sending astronauts to the Moon and then on to Mars, in a measured, sustainable way. The direction from Space Policy Directive-1 builds on the hard work NASA is doing on its Space Launch System rocket and Orion spacecraft, agency efforts to enable commercial partners, its work with international partners at the International Space Station in low-Earth orbit, and what NASA learns from its current robotic missions at the Moon and Mars. 15)
Figure 10: NASA Administrator Jim Bridenstine sent a video message to agency employees on 13 May 2019 about the president’s fiscal year 2020 budget amendment, which will support accelerated plans to land astronauts on the Moon by 2024 (video credit: NASA)
• April 9, 2019: The president directed NASA to land American astronauts on the Moon by 2024, and the agency is working to accelerate humanity’s return to the lunar surface by all means necessary. 18)
- “We’ve been given an ambitious and exciting goal. History has proven when we’re given a task by the president, along with the resources and the tools, we can deliver,” said NASA Administrator Jim Bridenstine. “We are committed to making this happen. We have the people to achieve it. Now, we just need bipartisan support and the resources to get this done.”
- Bridenstine confirmed at the 35th Space Symposium on April 9, 2019, that the agency’s proposed human lunar landing system architecture remains the plan to return crew to the surface as quickly as possible. The human lunar lander will be a public-private partnership working directly with American companies to expedite the return of Astronauts to the Moon’s surface by 2024. The South Pole continues to be the target of our exploration.
- In order to best accomplish our goals in the next five years, NASA is now going forward to the Moon in two phases.
- “First, we are focused on speed to land the next man, and first woman, on the Moon by 2024. Second, we will establish sustainable missions by 2028. To do that, we need our powerful Space Launch System to put the mass of reusable systems into deep space,” he said.
• March 11, 2019: The International Space Station partners have endorsed plans to continue the development of the Gateway, an outpost around the Moon that will act as a base to support both robots and astronauts exploring the lunar surface. 19)
- The MCB (Multilateral Coordination Board), which oversees the management of the Space Station, stressed its common hope for the Gateway to open up a cost-effective and sustainable path to the Moon and beyond. The announcement comes after several years of extensive study among space agencies who have developed a technically achievable design. The partnership includes European countries (represented by ESA), the United States (NASA), Russia (Roscosmos), Canada (CSA) and Japan (JAXA).
- “We are getting ready, together, to send humans farther into the Solar System than ever before. The lunar Gateway is the next big step in human exploration and we are working to make Europe a part of it,” says David Parker, ESA’s human and robotic exploration director.
- NASA’s Orion spacecraft will transport astronauts to the Gateway. Orion is powered by the European Service Module, which will give the crewed vehicle a final push to inject it into translunar orbit.
- Almost 50 years after the first human landing on the Moon, the Gateway will support human and robotic access to the lunar surface. “We will extend the presence of humans one thousand times farther into space compared to today’s International Space Station,” adds David Parker.
- The Gateway will offer a platform for scientific discovery in deep space and build invaluable experience for the challenges of future human missions to Mars.
- Nearly 400,000 km away from Earth, the Moon's orbit will provide excellent visibility of both the Earth and the Moon’s surface allowing it to relay communications.
- According to the board, the Gateway “will stimulate the development of advanced technologies, expand the emerging space economy, and continue to leverage the societal benefits of space exploration for citizens on Earth.”
- Canada has already confirmed its commitment to join NASA in the Gateway and contribute advanced robotics to the project, making the Canadian Space Agency the first partner agency.
- ESA’s potential involvement includes the ESPRIT (European System Providing Refueling Infrastructure and Telecommunications) module to provide communications and refueling of the Gateway and a science airlock for deploying science payloads and CubeSats.
• March 5, 2019: The ISS Multilateral Coordination Board (MCB), which oversees the management of the ISS, met on March 5th, 2019. Its members (NASA, CSA, ESA, the Government of Japan’s Ministry for Education, Culture, Sports, Science and Technology, and the State Space Corporation Roscosmos of Russia) acknowledged the recent 20th anniversary of the launch of the first International Space Station module and celebrated the success of the ISS partnership. This international team has not only built the space station and risen to the challenges of its day-to-day dynamic operation, but – most importantly – delivered tangible benefits to humanity. 20)
Figure 11: The MCB members from the United States, Canada, Europe, Japan, and Russia discussed their common interest in deploying a human outpost in the lunar vicinity as the next step, a Gateway that will serve as a way station for exploring the surface of the Moon. The MCB endorsed plans to continue developing the Gateway and welcomed each Agency’s intention to seek the necessary approvals for providing the elements, modules and capabilities shown in this graphic concept for Gateway configuration (image credit: NASA)
- Important outcomes of the ISS include both new scientific knowledge and technical innovation. These advancements address sustainable development here on Earth and help preparations to extend human presence further into our Solar System. The MCB highlighted the fact that more than 100 countries have now used the space station for research or education. Furthermore, representatives noted with satisfaction that the ISS is nurturing a growing economy in Low Earth Orbit research, business and services.
- Looking beyond the ISS, the MCB recalled the historic achievement almost fifty years ago of the first human landing on the Moon. It reviewed the extensive work carried out by the ISS partners to study concepts for extending human exploration to the Moon and subsequently to Mars. Emphasizing the importance of affordable and sustainable exploration, the MCB discussed their common interest in deploying a human outpost in the lunar vicinity as the next step. Known as the Gateway, it will serve as a way station one thousand times more distant from Earth than today’s ISS, to support exploration of the lunar surface.
- Within a broader open architecture for human lunar exploration, the MCB acknowledged the Gateway as a critical next step. The Gateway will support human and robotic access to the lunar surface, and build invaluable experience needed for the challenges of later human missions to Mars. The unique location of the Gateway will offer a platform for important scientific discovery in a deep space environment very different from that of the ISS and enable lunar surface exploration. Its special orbit will also provide excellent visibility of both the Earth and the Moon’s surface for communications relay purposes. It will stimulate the development of advanced technologies, expand the emerging space economy, and continue to leverage the societal benefits of space exploration for citizens on Earth. Gateway will ultimately enable international and commercial partners to participate in human exploration, research and technology development and will be foundational for establishing a sustained human presence around and on the Moon.
- Following several years of extensive study among the agencies culminating in a successful technical assessment, the MCB endorsed plans to continue the Gateway development. It welcomed each agency’s intention to proceed toward their respective stakeholders’ approval and funding processes for providing specific elements, modules, and capabilities to the Gateway and associated benefits based on a common concept (Figure 11).
- The MCB welcomed with enthusiasm Canada’s announcement on February 28th, 2019, that it would participate in the Gateway and contribute advanced robotics, making the Canadian Space Agency the first partner agency to join NASA in the Gateway.
- Finally, recalling the ambition and far-sighted decisions that led to the success of both Apollo and the ISS, MCB members affirmed their common hope that the Gateway should secure new achievements in the field of space exploration, serve as the next step on a sustainable path to the Moon and beyond, and inspire the next generation as a future success of international cooperation in science and technology.
ESA participation in NASA's Lunar Gateway venture
ESA (European Space Agency) and its Member States have laid out plans as to where the organization sees itself heading in the next few years and a stake in the Lunar gateway is high on its list of priorities. 21)
Using its E3P (European Exploration Envelope Program) as a springboard for ideas, the ESA Council has highlighted the agency’s desire for Europe to play a leading role in the global exploration of space and to achieve this, the council have identified three main areas in which to make an impact.
These include; negotiating agreements covering the elements of potential ESA contributions to the Lunar gateway, including both transportation and infrastructure; negotiating agreement(s) covering potential European contributions to an international Mars Sample Return mission or other sample return missions; and examining scenarios and mission concepts for lunar exploration missions supporting the objectives of the European scientific community.
The Participating States in the E3P Program have already begun preparations that could see Europe become a major player in the ‘Lunar gateway’ with a reform of a current legal act and with the commissioning of modules to be used as part of the gateway itself.
The Lunar gateway set out as a sole NASA initiative but has since agreed a partnership with Russia to build the first lunar space station. Placed farther from Earth than the current Space Station – but ironically not in a lunar orbit – the gateway will offer a staging post for missions to the Moon and Mars.
ESA is also busy building a European Service Module for NASA’s Orion spacecraft - another project designed to take humans deeper into space. Orion – named after one of the largest constellations in the night sky – will serve as the exploration vehicle that will carry crew to space, sustain astronauts during their missions, provide emergency abort capability and provide safe re-entry from deep space return velocities.
ESA’s Director of Human and Robotic Exploration David Parker says, “there’s no doubt that the next decade is going to be exciting for space exploration. ESA and its Member States are working hard to keep Europe at the heart of the journey of discovery and fascination that lies ahead.”
• September 20, 2018: ESA has commissioned Airbus for two studies for possible European involvement in the future human base in lunar orbit. The Gateway, previously known as the Deep Space Gateway (DSG) or Lunar Orbital Platform-Gateway (LOP-G), is a project involving the US, Russian, Canadian, Japanese and European space agencies (NASA, Roscosmos, CSA, JAXA and ESA). 22)
Over the next 15 months, Airbus will develop a concept for a habitation and research module as part of the first study (habitat, approximately 6.5 x 4.5 m and weighing some 9 tons). In the second study, Airbus will design a concept for an infrastructure element for refuelling, docking and telecommunications, which will also serve as an airlock for scientific equipment (known as Esprit, around 3 x 3 m and weighing around 4 tons). Both studies will be developed as part of a far-reaching European partnership.
Figure 12: The Gateway to serve as a staging point and hub for human missions to the Moon or Mars (image credit: Airbus, ESA)
Under NASA's overall design leadership, other elements – such as a second habitat, an airlock for scientific payloads and a logistics module - will be designed by international and commercial partners. NASA has plans to launch the first module - the central PPE (Power Propulsion Element) – into lunar orbit in the early 2020's.
“The experience and know-how that ESA and Airbus have gained during flagship projects such as the Columbus space laboratory, the ATV space transporter and the European service module for Orion provide solid foundations for the studies,” said Oliver Juckenhöfel, Head of On-Orbit Services and Exploration at Airbus. “When developing the new lunar platforms, robotic and human space exploration go hand in hand. Europe has a fantastic track record in both, and these two studies will help to ensure a strong European presence in future space exploration.”
David Parker, Director of Human and Robotic Exploration at ESA, said: "With these studies and other preparations, ESA aims to stay at the center of human space exploration. The Gateway will become humanity's most remote research outpost and we hope Europe will benefit from the world of innovation, discovery and excitement that lies ahead."
Unlike the International Space Station (ISS), the Gateway is not intended to be continually inhabited. It is envisaged that the lunar platform will act as a staging point for human missions to the Moon or Mars, and testing is planned for a series of technologies and procedures that will be needed.
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The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: ”Observation of the Earth and Its Environment: Survey of Missions and Sensors” (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (firstname.lastname@example.org).