Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “cislunar”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9

The Asteroid Redirect Mission (ARM)

The National Aeronautics and Space Administration (NASA) is developing a robotic mission to visit a large near-Earth asteroid (NEA), collect a multi-ton boulder from its surface, and redirect it into a stable orbit around the Moon. Once returned to cislunar space in the mid-2020s, astronauts will explore the boulder and return to Earth with samples. This Asteroid Redirect Mission (ARM) is part of NASA's plan to advance the technologies, capabilities, and spaceflight experience needed for a human mission to the Martian system in the 2030s. Subsequent human and robotic missions to the asteroidal material would also be facilitated by its return to cislunar space. Although ARM is primarily a capability demonstration mission (i.e., technologies and associated operations), there exist significant opportunities to advance our knowledge of small bodies in the synergistic areas of science, planetary defense, asteroidal resources and in-situ resource utilization (ISRU), and capability and technology demonstrations. In order to maximize the knowledge return from the mission, NASA is organizing an ARM Investigation Team, which is being preceded by the Formulation Assessment and Support Team. These teams will be comprised of scientists, technologists, and other qualified and interested individuals to help plan the implementation and execution of ARM. An overview of robotic and crewed segments of ARM, including the mission requirements, NEA targets, and mission operations, will be provided along with a discussion of the potential opportunities associated with the mission.

Abell, Paul↗

NASA's Space Launch System: A New Opportunity for CubeSats

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. Together with the Orion crew vehicle and ground operations at NASA's Kennedy Space Center in Florida, SLS is a foundational capability for NASA's Journey to Mars. From the beginning of the SLS flight program, utilization of the vehicle will also include launching secondary payloads, including CubeSats, to deep-space destinations. Currently, SLS is making rapid progress toward readiness for its first launch in 2018, using the initial configuration of the vehicle, which is capable of delivering 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight, Exploration Mission-1, SLS will launch an uncrewed test flight of the Orion spacecraft into distant retrograde orbit around the moon. Accompanying Orion on SLS will be 13 CubeSats, which will deploy in cislunar space. These CubeSats will include not only NASA research, but also spacecraft from industry and international partners and potentially academia. Following its first flight and potentially as early as its second, which will launch a crewed Orion spacecraft into cislunar space, SLS will evolve into a more powerful configuration with a larger upper stage. This configuration will initially be able to deliver 105 t to LEO and will continue to be upgraded to a performance of greater than 130 t to LEO. While the addition of the more powerful upper stage will mean a change to the secondary payload accommodations from Block 1, the SLS Program is already evaluating options for future secondary payload opportunities. Early discussions are also already underway for the use of SLS to launch spacecraft on interplanetary trajectories, which could open additional opportunities for CubeSats. This presentation will include an overview of the SLS vehicle and its capabilities, including the current status of progress toward first launch. It will also explain the opportunities the vehicle offers for CubeSats and secondary payloads, including an overview of the CubeSat manifest for Exploration Mission-1 in 2018.

Hitt, David↗

Architecture Study for a Fuel Depot Supplied from Lunar Resources

Heretofore, discussions of space fuel depots assumed the depots would be supplied from Earth. However, the confirmation of deposits of water ice at the lunar poles in 2009 suggests the possibility of supplying a space depot with liquid hydrogen/liquid oxygen produced from lunar ice. This architecture study sought to determine the optimum architecture for a fuel depot supplied from lunar resources. Four factors - the location of propellant processing (on the Moon or on the depot), the location of the depot (on the Moon or in cislunar space), and if in cislunar space, where (LEO, GEO, or Earth-Moon L1), and the method of propellant transfer (bulk fuel or canister exchange) were combined to identify 18 potential architectures. Two design reference missions (DRMs) - a satellite servicing mission and a cargo mission to Mars - were used to create demand for propellants, while a third DRM - a propellant delivery mission - was used to examine supply issues. The architectures were depicted graphically in a network diagram with individual segments representing the movement of propellant from the Moon to the depot, and from the depot to the customer

Perrin, Thomas M.↗

End-to-End Trajectory for Conjunction Class Mars Missions Using Hybrid Solar-Electric/Chemical Transportation System

NASA's Human Spaceflight Architecture Team is developing a reusable hybrid transportation architecture in which both chemical and solar-electric propulsion systems are used to deliver crew and cargo to exploration destinations. By combining chemical and solar-electric propulsion into a single spacecraft and applying each where it is most effective, the hybrid architecture enables a series of Mars trajectories that are more fuel efficient than an all chemical propulsion architecture without significant increases to trip time. The architecture calls for the aggregation of exploration assets in cislunar space prior to departure for Mars and utilizes high energy lunar-distant high Earth orbits for the final staging prior to departure. This paper presents the detailed analysis of various cislunar operations for the EMC Hybrid architecture as well as the result of the higher fidelity end-to-end trajectory analysis to understand the implications of the design choices on the Mars exploration campaign.

Chai, Patrick R.↗

NASA's Space Launch System: Deep-Space Delivery for Smallsats

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. While primarily focused on launching the large systems needed for crewed spaceflight beyond Earth orbit, SLS also offers a game-changing capability for the deployment of small satellites to deep-space destinations, beginning with its first flight. Currently, SLS is making rapid progress toward readiness for its first launch in two years, using the initial configuration of the vehicle, which is capable of delivering 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight test of the Orion spacecraft around the moon, accompanying Orion on SLS will be small-satellite secondary payloads, which will deploy in cislunar space. The deployment berths are sized for "6U" CubeSats, and on EM-1 the spacecraft will be deployed into cislunar space following Orion separate from the SLS Interim Cryogenic Propulsion Stage. Payloads in 6U class will be limited to 14 kg maximum mass. Secondary payloads on EM-1 will be launched in the Orion Stage Adapter (OSA). Payload dispensers will be mounted on specially designed brackets, each attached to the interior wall of the OSA. For the EM-1 mission, a total of fourteen brackets will be installed, allowing for thirteen payload locations. The final location will be used for mounting an avionics unit, which will include a battery and sequencer for executing the mission deployment sequence. Following the launch of EM-1, deployments of the secondary payloads will commence after sufficient separation of the Orion spacecraft to the upper stage vehicle to minimize any possible contact of the deployed CubeSats to Orion. Currently this is estimated to require approximately 4 hours. The allowed deployment window for the CubeSats will be from the time the upper stage disposal maneuvers are complete to up to 10 days after launch. The upper stage will fly past the moon at a perigee of approximately 100km, and this closest approach will occur about 5 days after launch. The limiting factor for the latest deployment time is the available power in the sequencer system. Several NASA Mission Directorates were involved in the development of programs for the competition, selection, and development of EM-1 payloads that support directorate priorities. CubeSat payloads on EM-1 will include both NASA research experiments and spacecraft developed by industry, international and potentially academia partners. The Human Exploration and Operations Mission Directorate (HEOMD) Advanced Exploration Systems (AES) Division was allocated five payload opportunities on the EM-1 mission. Near Earth Asteroid (NEA) Scout is designed to rendezvous with and characterize a candidate NEA. A solar sail, an innovation the spacecraft will demonstrated for the CubeSat class, will provide propulsion. Lunar Flashlight will use a green propellant system and will search for potential ice deposits in the moon's permanently shadowed craters. BioSentinel is a yeast radiation biosensor, planned to measure the effects of space radiation on deoxyribonucleic acid (DNA). Lunar Icecube, a collaboration with Morehead State University, will prospect for water in ice, liquid, and vapor forms as well as other lunar volatiles from a low-perigee, highly inclined lunar orbit using a compact Infrared spectrometer. Skyfire, a partnership with Lockheed Martin, is a technology demonstration mission that will perform a lunar flyby, collecting spectroscopy, and thermography data to address questions related to surface characterization, remote sensing, and site selection. NASA's Space Technology Mission Directorate (STMD) was allocated three payload opportunities on the EM-1 mission. These slots will be filled via the Centennial Challenges Program, NASA's flagship program for technology prize competitions, which directly engages the public, academia, and industry in open prize competitions to stimulate innovation. The NASA Science Mission Directorate (SMD) was allocated two payload opportunities on the EM-1 mission. The CubeSat Mission to Study Solar Particles (CuSP) payload will study the sources and acceleration mechanisms of solar and interplanetary particles in near-Earth orbit, support space weather research by determining proton radiation levels during Solar Energetic Particle (SEP) events and identifying suprathermal properties that could help predict geomagnetic storms. The LunaH-Map payload will help scientists understand the quantity of H-bearing materials in lunar cold traps (~10 km), determine the concentration of H-bearing materials with 1m depth, and constrain the vertical distribution of H-bearing materials. The final three payload opportunities for the EM-1 mission were allocated for NASA's international space agency counterparts. The flight opportunities are intended to benefit the international space agency and NASA as well as further the collective space exploration goals. ArgoMoon is sponsored by ESA/ASI and will fly along with the ICPS on its disposal trajectory to perform proximity operations with the ICPS post-disposal, take external imagery of engineering and historical significance, and perform an optical communications demonstration. EQUULEUS, sponsored by JAXA, will fly to a libration orbit around the Earth-Moon L2 point and demonstrate trajectory control techniques within the Sun-Earth- Moon region for the first time by a nano spacecraft. The mission will also contribute to the future human exploration scenario by understanding the radiation environment in geospace and deep space, characterizing the flux of impacting meteors on the far side of the moon, and demonstrating the future deep space exploration scenario using the "deep space port" at Lagrange points. OMOTENASHI, also sponsored by JAXA, will land the smallest lunar lander to date on the lunar surface to demonstrate the feasibility of the hardware for distributed cooperative exploration system. Small landers will enable multi-point exploration, which is complimentary with large-scale human exploration. Once on the lunar surface, the OMOTENASHI spacecraft will observe the radiation and soil environments of the lunar surface by active radiation measurements and soil shear measurements. Following EM-1, Space Launch System will evolve to the more-powerful Block 1B configuration, which uses a new Exploration Upper Stage to increase the vehicle's LEO payload capability from 70 t to 105 t. With that transition, the Orion Stage Adapter, which will carry the secondary payloads on EM-1, will be phased out, and a new Universal Stage Adapter will be introduced, creating opportunities for flying larger secondary payloads. This paper will provide a brief status of SLS progress toward first launch; an overview of smallsat accommodations, integration, and operations on EM-1; information about the specific payloads flying on that launch; and a discussion of future accommodations and opportunities for secondary payloads on SLS for Exploration Mission-2 and beyond.

Robinson, Kimberly F.↗

NASA's Space Launch System: Deep-Space Opportunities for SmallSats

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. While primarily focused on launching the large systems needed for crewed spaceflight beyond Earth orbit, SLS also offers a game-changing capability for the deployment of small satellites to deep-space destinations, beginning with its first flight. Currently, SLS is making rapid progress toward readiness for its first launch in two years, using the initial configuration of the vehicle, which is capable of delivering 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight test of the Orion spacecraft around the moon, accompanying Orion on SLS will be small-satellite secondary payloads, which will deploy in cislunar space. The deployment berths are sized for "6U" CubeSats, and on EM-1 the spacecraft will be deployed into cislunar space following Orion separate from the SLS Interim Cryogenic Propulsion Stage. Payloads in 6U class will be limited to 14 kg maximum mass. Secondary payloads on EM-1 will be launched in the Orion Stage Adapter (OSA). Payload dispensers will be mounted on specially designed brackets, each attached to the interior wall of the OSA. For the EM-1 mission, a total of fourteen brackets will be installed, allowing for thirteen payload locations. The final location will be used for mounting an avionics unit, which will include a battery and sequencer for executing the mission deployment sequence. Following the launch of EM-1, deployments of the secondary payloads will commence after sufficient separation of the Orion spacecraft to the upper stage vehicle to minimize any possible contact of the deployed cubesats to Orion. Currently this is estimated to require approximately 4 hours. The allowed deployment window for the cubesats will be from the time the upper stage disposal maneuvers are complete to up to 10 days after launch. The upper stage will fly past the moon at a perigee of approximately 100km, and this closest approach will occur about 5 days after launch. The limiting factor for the latest deployment time is the available power in the sequencer system. Several NASA Mission Directorates were involved in the development of programs for the competition, selection, and development of EM-1 payloads that support directorate priorities. CubeSat payloads on EM-1 will include both NASA research experiments and spacecraft developed by industry, international and potentially academia partners. The Human Exploration and Operations Mission Directorate (HEOMD) Advanced Exploration Systems (AES) Division was allocated five payload opportunities on the EM-1 mission. Near Earth Asteroid (NEA) Scout is designed to rendezvous with and characterize a candidate NEA. A solar sail, an innovation the spacecraft will demonstrated for the CubeSat class, will provide propulsion. Lunar Flashlight will use a green propellant system and will search for potential ice deposits in the moon's permanently shadowed craters. BioSentinel is a yeast radiation biosensor, planned to measure the effects of space radiation on deoxyribonucleic acid (DNA). Lunar Icecube, a collaboration with Morehead State University, will prospect for water in ice, liquid, and vapor forms as well as other lunar volatiles from a low-perigee, highly inclined lunar orbit using a compact Infrared spectrometer. Skyfire, a partnership with Lockheed Martin, is a technology demonstration mission that will perform a lunar flyby, collecting spectroscopy, and thermography data to address questions related to surface characterization, remote sensing, and site selection. NASA's Space Technology Mission Directorate (STMD) was allocated three payload opportunities on the EM-1 mission. These slots will be filled via the 2 Centennial Challenges Program, NASA's flagship program for technology prize competitions, which directly engages the public, academia, and industry in open prize competitions to stimulate innovation. The NASA Science Mission Directorate (SMD) was allocated two payload opportunities on the EM-1 mission. The CubeSat Mission to Study Solar Particles (CuSP) payload will study the sources and acceleration mechanisms of solar and interplanetary particles in near-Earth orbit, support space weather research by determining proton radiation levels during Solar Energetic Particle (SEP) events and identifying suprathermal properties that could help predict geomagnetic storms. The LunaH-Map payload will help scientists understand the quantity of H-bearing materials in lunar cold traps (~10 km), determine the concentration of H-bearing materials with 1m depth, and constrain the vertical distribution of H-bearing materials. The final three payload opportunities for the EM-1 mission were allocated for NASA's international space agency counterparts. The flight opportunities are intended to benefit the international space agency and NASA as well as further the collective space exploration goals. ArgoMoon is sponsored by ESA/ASI and will fly along with the ICPS on its disposal trajectory to perform proximity operations with the ICPS post-disposal, take external imagery of engineering and historical significance, and perform an optical communications demonstration. EQUULEUS, sponsored by JAXA, will fly to a libration orbit around the Earth-Moon L2 point and demonstrate trajectory control techniques within the Sun-Earth-Moon region for the first time by a nano spacecraft. The mission will also contribute to the future human exploration scenario by understanding the radiation environment in geospace and deep space, characterizing the flux of impacting meteors on the far side of the moon, and demonstrating the future deep space exploration scenario using the "deep space port" at Lagrange points. OMOTENASHI, also sponsored by JAXA, will land the smallest lunar lander to date on the lunar surface to demonstrate the feasibility of the hardware for distributed cooperative exploration system. Small landers will enable multi-point exploration, which is complimentary with large-scale human exploration. Once on the lunar surface, the OMOTENASHI spacecraft will observe the radiation and soil environments of the lunar surface by active radiation measurements and soil shear measurements. Following EM-1, Space Launch System will evolve to the more-powerful Block 1B configuration, which uses a new Exploration Upper Stage to increase the vehicle's LEO payload capability from 70 t to 105 t. With that transition, the Orion Stage Adapter, which will carry the secondary payloads on EM-1, will be phased out, and a new Universal Stage Adapter will be introduced, creating opportunities for flying larger secondary payloads. This paper will provide a brief status of SLS progress toward first launch; an overview of smallsat accommodations, integration, and operations on EM-1; information about the specific payloads flying on that launch; and a discussion of future accommodations and opportunities for secondary payloads on SLS for Exploration Mission-2 and beyond.

Robinson, Kimberly F.↗

MoonBEAM: Gamma-Ray Burst Detectors on SmallSAT

Moon Burst Energetics All-sky Monitor (MoonBEAM) is a CubeSat concept of deploying gamma-ray detectors in cislunar space to improve localization precision for gamma-ray bursts by utilizing the light travel time difference between a spacecraft in Earth and cislunar orbit. MoonBEAM is designed with high TRL components to be flight ready. This instrument would probe the extreme processes in cosmic collision of compact objects and facilitate multi-messenger time-domain astronomy to explore the end of stellar life cycles and black hole formations.

gamma-ray burst cubesat↗

NASA: 60 Years and Counting...

Sputnik launched on 4 Oct 1057. On July 29, 1958, Eisenhower signed the National Aeronautics and Space Act, the creation of NASA. The Soviets launched the first human into orbit, Yuri Gagarin, on April 12, 1961. On 5 May 1961, Alan Shepard's Freedom 7 Mercury capsule lifted off at 9:34 a.m. from Launch Complex 5 at Cape Canaveral Air Force Station, and flew a suborbital trajectory lasting 15 minutes and 22 seconds, America's first man in space. On 25 May 1961, Kennedy delivered a speech to a joint session of Congress. In that speech, he stated "I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth." The rest, as they say, is history. Project Mercury, the first U.S. program to put humans in space, made 25 flights, six of which carried astronauts between 1961 and 1963. The Gemini program primarily tested equipment and mission procedures and trained astronauts and ground crews for future Apollo missions to the Moon. Exactly eight years, one month and 26 days after President Kennedy challenged Americans to reach for the Moon, Project Apollo landed the first humans on the lunar surface and returned them safely to Earth. In 1973, Skylab expeditions paved the way for the International Space Station. Over 30 years, NASA's space shuttle fleet, ”Columbia, Challenger, Discovery, Atlantis and Endeavour,” flew 135 missions and carried 355 different people to space. The space shuttle carried people into orbit repeatedly; launched, recovered and repaired satellites; conducted cutting-edge research; and built the largest structure in space, the International Space Station. Tragically, NASA lost two crews of seven in the 1986 Challenger accident and the 2003 Columbia accident. The International Space Station is a model for global cooperation and scientific advancements that is enabling growth of private industry in low-Earth orbit and development of new technologies to advance human space exploration. Built between 1998 and 2011, the space station has housed humans continuously since Nov. 2, 2000. NASA has contracted with commercial companies SpaceX, Orbital ATK, and Sierra Nevada Corporation to deliver science investigations, cargo, and supplies to the crews living in space, and soon Boeing and SpaceX will transport astronauts to and from the station. Today, NASA is working on many fronts to advance man's presence in space. NASA's Exploration Campaign will establish U.S. preeminence in cislunar space through the operations and the deployment of a U.S.-led Lunar Orbital Platform-Gateway (LOPG). Together with the Orion and SLS Programs, the LOPG is central to advancing and sustaining human space exploration goals, and is the unifying single stepping off point for human cislunar operations, lunar surface access and missions to Mars. As one might expect, EMC for all this activity is challenging, to say the least. In the next half-hour or so, I will talk about some of those challenges and how the different programs are meeting them.

Scully, Bob↗

International Space Station as a Development Testbed for Advanced Environmental Control and Life Support Systems

Since the beginning of human spaceflight, mission durations have steadily increased. Current mission durations onboard the International Space Station are multiple months, but future exploration missions to cislunar space and beyond will require multiple year durations. In addition, missions to cislunar or deep space will encounter a much harsher environment than the current ISS low-earth orbit missions, with relation to radiation, isolation, and lack of timely available support from Earth. To meet the challenges of deep space, so-called "exploration missions" will require Environmental Control and Life Support systems with higher performance, lower mass and logistics requirements, and more endurance than are possible with current operational systems on board the International Space Station. As a currently operational human-occupied platform, the International Space Station presents a unique opportunity to act as a testbed for development of advanced next-generation Environmental Control and Life Support Systems, such that these systems may be tested, proven, and refined for eventual deployment on deep space human exploration missions. This paper will outline the history, progress to date, and future plans for efforts to design, select, build, test and fly Advanced Environmental Control and Life Support Systems on the ISS.

Shaw, Laura A.↗

Summary of Gateway Power and Propulsion Element (PPE) Studies

NASA's Power and Propulsion Element (PPE) is based on a joint industry/NASA demonstration of an advanced solar electric propulsion powered spacecraft to meet commercial and NASA objectives. The PPE can establish the initial presence in cislunar space for the Gateway through initial operations and the subsequent deployment of additional partner-provided elements for the cislunar platform. Five commercial vendors were selected to conduct PPE studies which addressed key drivers for PPE development and support for the Gateway concept formulation. The study vendors focused on their performance trades and assessing their strategic capabilities, leveraging their existing and planned capabilities for PPE development. The industry studies examined differences between prior Solar Electric Propulsion (SEP) mission concepts, expected industry capabilities, and potential needs supporting NASA's Gateway concept. These studies provided data on commercial capabilities relevant to NASA's exploration needs and reduced risk for a new, powerful, and efficient SEP-based PPE spacecraft.

Irimies, David↗

Power and Propulsion Element (PPE) Spacecraft Reference Trajectory Document

This document captures example reference trajectories for the PPE including a reference delivery orbit and orbit maintenance, an example cislunar orbit transfer and end-of-mission (EOM) disposal trajectory. The flexibility of electric propulsion offers, by its low thrust nature, multiple different trajectory options to transfer from one orbit to another. The trajectories captured in this document are representative examples of a low thrust transfer from the NRHO and to multiple cislunar orbits. This document provides a consistent set of data from mission design to be used in the design of the vehicle capable of flying the trajectory described. The data in this document will be used to create conference papers. In order to do so, we are ending this document through for external release.

Melissa L Mcguire↗

Exploration EVA System Concept of Operations

The Exploration Extravehicular Activity (xEVA) System concept of operations (con ops) captures the National Aeronautics and Space Administration’s (NASA’s) current aims future missions to all potential Exploration destinations. This document captures the mission architectures, stakeholder expectations, and high level definitions of the capabilities and interfaces associated with the xEVA System. This includes missions to Gateway in cislunar space, the lunar surface, a redirected asteroid in cislunar space, Near Earth Asteroids (NEA), Mars’ orbit, the moons of Mars (Phobos and Deimos), and the surface of Mars. These missions, which include microgravity, milli-gravity, and partial-gravity surface EVAs, will involve a variety of engineering (maintenance, contingency, pioneering, construction) and science tasks. This document also captures information concerning vehicles and habitats with which the xEVA System will interface. The concepts of operations (con ops) detailed in this document are informed by the Artemis Program and a multitude of Exploration studies, and are also influenced by various integrated operational analog testing.

David Coan↗

Legacy of the Asteroid Redirect Robotic Mission (ARRM)

NASA’s proposed Asteroid Redirect Robotic Mission (ARRM) began with the recognition in a 2010 NASA study that emerging high-power solar electric propulsion technology could be used to rendezvous with, capture, and return an entire, very small (~10,000 kg), near Earth asteroids to the International Space Station. A 2011 workshop by the Keck Institute for Space Studies (KISS) extended the earlier NASA study to asteroid masses of order 500,000 kg by returning them to cislunar space. Subsequent detailed NASA studies in 2013-2014 confirmed the feasibility of this concept. This led to the establishment of the Asteroid Redirect Mission program that consisted of a robotic mission to return multiple tons of asteroid material to cislunar space and a crewed mission to rendezvous with the robotic vehicle, perform two extra vehicular activities (EVAs), collect samples of the asteroid material, and return this material to Earth. Implementation of ARRM got midway through Phase B before being cancelled in April 2017. Although ARRM was cancelled, it has left a near-term legacy of positive impacts to the human spaceflight community, the planetary defense community, the deep space science community, and asteroid mining interests.

Brophy, John R.↗

Principles for a Practical Moon Base

NASA planning for the human space flight frontier is now coming into alignment with goals promoted by other planetary-capable national space agencies. US policy aims to achieve the “horizon goal” of Humans to Mars through significant learning about systems, operations, and partnerships in the cislunar and lunar-surface environment first. US Space Policy Directive 1 made this shift explicit: “the United States will lead the return of humans to the Moon for long-term exploration and utilization, followed by human missions to Mars and other destinations”. The stage is now set for sufficient public and private American investment in a wide range of lunar activities. Assumptions about Moon base architectures and operations are likely to drive the invention of requirements that will in turn govern development of systems, commercial-services purchase agreements, and priorities for technology investment. Yet some fundamental architecture-shaping lessons already captured in the literature are not evident drivers, and remain absent from most depictions of lunar base concepts. A prime example is general failure to recognize that most of the time (i.e., before and between intermittent human occupancy), a Moon base must be robotic: most of the activity, most of the time, must be implemented by robot agents rather than astronauts. This paper reviews key findings of a seminal robotic-base design-operations analysis commissioned by NASA in 1989. It culminates by discussing implications of these lessons for today’s Moon Village and SPD-1 paradigms: exploration by multiple actors; public-private partnership development and operations; cislunar infrastructure; production-quantity exploitation of volatile resources near the poles to bootstrap further space activities; autonomy capability that was frontier in 1989 but now routine within terrestrial industry. We need to engineer today’s generation of practical, justifiable, and inspirational Moon base concepts.

Sherwood, Brent↗

The Space Superhighway: Systems Analysis of an In-Space Logistics Delivery Network

The number of assets in cislunar space is anticipated to dramatically increase in the coming decades. Many of these newer spacecraft are being designed to take advantage of capabilities currently in development like In-Space Servicing Assembly and Manufacturing (ISAM). Additionally, the National Aeronautics and Space Administration (NASA) intends to develop and maintain a human-lunar presence that will then serve as a steppingstone for human missions to Mars. With continued growth in space operations, the combined demand for payload and propellant delivery in cislunar space could exceed 1,000 t annually in the next decade. The Space Superhighway principally consists of a logistics network and is intended to both use and proliferate ISAM in order to meet projected payload demands. Several architecture and vehicle-level trade studies are explored in order to better understand what in-space logistics networks may be feasible. The network consists of commercial launch vehicles, resupply tankers, orbital depots, and in-space tugs. This work specifically analyzes high-level trades such as: launch and in-space vehicle propulsion systems, vehicle size, staging orbit, level of vehicle reuse, reuse method, and propellant management strategy. Each of the trades are analyzed across several destination orbits such as Low-Earth Orbit (LEO) and Near-Rectilinear Halo Orbit (NRHO). Several payload types are also considered such as storable and cryogenic chemical propellants, electric propellants, crew logistics, spares, smallsats, and satellite piece parts.

Daniel J Tiffin↗

The Moon Burst Energetics All-sky Monitor (MoonBEAM)

MoonBEAM is a SmallSat concept placed in cislunar orbit developed to study the progenitors and multimessenger/multiwavelength signals of transient relativistic jets and outflows and determine the conditions that lead to the launching of a transient relativistic jet. The distinguishing advantage of MoonBEAM is the instantaneous all-sky coverage, maximizing the gamma-ray transients observations and providing upper limits for nondetections. Gamma-ray observatories in low Earth orbit are not able to survey the entire sky at a given time due to Earth blockage as well as detector downtime from the high particle activity in the South Atlantic Anomaly region. The long baseline provided from a cislunar orbit, allows MoonBEAM to constrain the localization annulus when combined with a gamma-ray instrument in low Earth orbit utilizing the timing triangulation technique. Improving the localization precision of a gamma-ray burst aids the gravitational wave follow-up community in reducing the region needed to be searched to locate and identify the afterglow and kilanova emission. Furthermore, by providing a different vantage point for a gamma-ray detection, MoonBEAM can help extend the gravitational wave detection horizon by increasing the confidence of a simultaneous marginal gravitational wave signal. Through the all-sky coverage, MoonBEAM will also provide insight into the conditions that lead to a successful relativistic jet, instead of a shock breakout event, or a completely failed jet in the case of core collapse supernovae.

Gamma-ray Bursts↗

Space Nuclear Propulsion for Deep Space Science Missions

The use of nuclear thermal propulsion (NTP) 1 and nuclear electric propulsion (NEP) 2 systems on deep space science missions to the outer planets and into the interstellar medium 3 can yield significant spacecraft system and mission performance benefits and improvements relative to the use of conventional chemical propulsion systems. Several recent and ongoing programs are developing the technologies and systems required to realize a near-term deep space nuclear propulsion capability. NTP provides improved propulsion efficiencies compared to chemical propulsion, while also providing substantial thrust. This combination of high thrust and increased specific impulse (I_sp) provides high acceleration and extended thrusting periods, enabling greatly reduced trip-times on certain types of missions compared to various propulsive alternatives. For examples, compared to a baseline mission using chemical propulsion, NTP-powered missions to Jupiter or Uranus could deliver approximately 2.4-3.6 times more payload (in the case of Jupiter, the payload delivery is significantly larger than the Juno spacecraft). In this comparison, the higher end of the payload advantage is obtained when the trip time is held equal for the NTP-powered vehicle and a vehicle using a chemical propulsion departure stage. NTP systems are presently under development by multiple government agencies. NASA’s Space Nuclear Propulsion (SNP) project aims to demonstrate a hydrogen-fed NTP engine at 900 s specific impulse (I_sp) and approximately 10-15 klb_f of thrust. DARPA’s Demonstration Rocket for Agile Cislunar Operations (DRACO) program is targeting a demonstration of an NTP system in the cislunar space between the Earth and the Moon. An appropriately phased development plan that applies the development of the reactor technology for an NTP engine in this performance class and leverages mature, existing liquid rocket component hardware provides a path to a lower cost propulsion system that can be realized on a shorter development schedule. NEP, with high Isp in the 2,000-8,000 s range, can also provide advantages over chemical propulsion, including a much greater payload delivery mass and the flexibility for planners to trade between delivered mass and a wider window of mission trajectory options. Electric propulsion (EP) systems have demonstrated great utility, performing notably on the Dawn mission to enable rendezvous and orbital insertion at two separate bodies, Vesta and Ceres. An NEP-powered vehicle would have a similar capability to visit multiple bodies, loitering at each before moving to the next. A 10 kW_e NEP system provides a power- rich environment on the spacecraft that is simply not possible using present radioisotope power systems, giving mission planners more scientific instrument and communication hardware options. Several programs and projects are presently developing NEP systems and subsystems in the 10 kW_e power range, leveraging past reactor work and recent nuclear power generation risk-reduction demonstration activities such as the Demonstration Using Flattop Fission (DUFF) and the Kilopower Reactor Using Stirling TechnologY (KRUSTY). The goal of the Air Force Research Laboratory’s Joint Energy Technology Supplying On-Orbit Nuclear Power (JETSON) program is an in-space demonstration vehicle that has a 10 kW_e -class fission power source. These past and present efforts can be combined with the ongoing development of 10 kW_e -class electric propulsion systems (notably the NEXT-C ion thruster or the Hall-effect thrusters for Power and Propulsion Element of the Lunar Gateway) to provide a pathway to a low-cost, reliable NEP system for deep space science application.

Kurt A. Polzin↗

Space Nuclear Propulsion for Deep Space Science Missions

The use of nuclear thermal propulsion (NTP) 1 and nuclear electric propulsion (NEP) 2 systems on deep space science missions to the outer planets and into the interstellar medium 3 can yield significant spacecraft system and mission performance benefits and improvements relative to the use of conventional chemical propulsion systems. Several recent and ongoing programs are developing the technologies and systems required to realize a near-term deep space nuclear propulsion capability. NTP provides improved propulsion efficiencies compared to chemical propulsion, while also providing substantial thrust. This combination of high thrust and increased specific impulse (I_sp) provides high acceleration and extended thrusting periods, enabling greatly reduced trip-times on certain types of missions compared to various propulsive alternatives. For examples, compared to a baseline mission using chemical propulsion, NTP-powered missions to Jupiter or Uranus could deliver approximately 2.4-3.6 times more payload (in the case of Jupiter, the payload delivery is significantly larger than the Juno spacecraft). In this comparison, the higher end of the payload advantage is obtained when the trip time is held equal for the NTP-powered vehicle and a vehicle using a chemical propulsion departure stage. NTP systems are presently under development by multiple government agencies. NASA’s Space Nuclear Propulsion (SNP) project aims to demonstrate a hydrogen-fed NTP engine at 900 s specific impulse (I_sp) and approximately 10-15 klb_f of thrust. DARPA’s Demonstration Rocket for Agile Cislunar Operations (DRACO) program is targeting a demonstration of an NTP system in the cislunar space between the Earth and the Moon. An appropriately phased development plan that applies the development of the reactor technology for an NTP engine in this performance class and leverages mature, existing liquid rocket component hardware provides a path to a lower cost propulsion system that can be realized on a shorter development schedule. NEP, with high Isp in the 2,000-8,000 s range, can also provide advantages over chemical propulsion, including a much greater payload delivery mass and the flexibility for planners to trade between delivered mass and a wider window of mission trajectory options. Electric propulsion (EP) systems have demonstrated great utility, performing notably on the Dawn mission to enable rendezvous and orbital insertion at two separate bodies, Vesta and Ceres. An NEP-powered vehicle would have a similar capability to visit multiple bodies, loitering at each before moving to the next. A 10 kW_e NEP system provides a power- rich environment on the spacecraft that is simply not possible using present radioisotope power systems, giving mission planners more scientific instrument and communication hardware options. Several programs and projects are presently developing NEP systems and subsystems in the 10 kW_e power range, leveraging past reactor work and recent nuclear power generation risk-reduction demonstration activities such as the Demonstration Using Flattop Fission (DUFF) and the Kilopower Reactor Using Stirling TechnologY (KRUSTY). The goal of the Air Force Research Laboratory’s Joint Energy Technology Supplying On-Orbit Nuclear Power (JETSON) program is an in-space demonstration vehicle that has a 10 kW_e -class fission power source. These past and present efforts can be combined with the ongoing development of 10 kW_e -class electric propulsion systems (notably the NEXT-C ion thruster or the Hall-effect thrusters for Power and Propulsion Element of the Lunar Gateway) to provide a pathway to a low-cost, reliable NEP system for deep space science application.

Kurt A. Polzin↗