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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.

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At least 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Cold Gas Reaction Control System for the Near Earth Asteroid Scout CubeSat

This paper describes the Attitude Control System (ACS) for the Near Earth Asteroid (NEA) Scout cubesat with particular focus on the Reaction Control System (RCS). NEA Scout is a 6-Unit cubesat with an 86-square-meter solar sail. NEA Scout will launch on Space Launch System (SLS) Exploration Mission 1 (EM-1), currently scheduled to launch in 2019. The spacecraft will rendezvous with an asteroid after a two year journey, and will conduct science imagery. The ACS consists of three major actuating subsystems: a Reaction Wheel (RW) control system, a Reaction Control System (RCS), and an Active Mass Translator (AMT) system. The three subsystems allow for a wide range of spacecraft attitude control capabilities, needed for the different phases of the NEA-Scout mission. The RCS performs a number of critical functions during NEA Scout’s mission. These requirements are described and the performance for achieving these requirements is shown. Moreover, NEA Scout employs a solar sail for long-duration propulsion. Solar sails are large, flexible structures that typically have low bending-mode frequencies. This paper demonstrates a robust performance while avoiding excitation of the sail’s structural modes.

Stiltner, Brandon C.↗
NASA NTRS2017

Cold Gas Reaction Control System for the Near Earth Asteroid Scout CubeSat

This paper describes the Attitude Control System (ACS) for the Near Earth Asteroid (NEA) Scout cubesat with particular focus on the Reaction Control System (RCS). NEA Scout is a 6U cubesat with an 86 square-meter solar sail. NEA Scout will launch on Space Launch System (SLS) Exploration Mission 1 (EM-1), currently scheduled to launch in 2018. The spacecraft will rendezvous with an asteroid after a two year journey, and will conduct science imagery. The ACS consists of three major actuating subsystems: a Reaction Wheel (RW) control system, a Reaction Control System (RCS), and an Active Mass Translator (AMT) system. The three subsystems allow for a wide range of spacecraft attitude control capabilities, needed for the different phases of the NEA-Scout mission. The RCS performs a number of critical functions during NEA Scout's mission. These requirements are described and the performance for achieving these requirements is shown. Moreover, NEA Scout employs a solar sail for long-duration propulsion. Solar sails are large, flexible structures that typically have low bending-mode frequencies. This paper demonstrates a robust performance while avoiding excitation of the sail's structural modes.

Stiltner, Brandon C.↗
NASA NTRS2017

Lessons for Interstellar Travel from the Guidance and Control Design of the Near Earth Asteroid Scout Solar Sail Mission

NASA is developing the Near Earth Asteroid (NEA) Scout mission that will use a solar sail to travel to an asteroid where it will perform a slow flyby to acquire science imagery. A guidance and control system was developed to meet the science and trajectory requirements. The NEA Scout design process can be applied to an interstellar or precursor mission that uses a beam propelled sail. The scientific objectives are met by accurately targeting the destination trajectory position and velocity. The destination is targeted by understanding the force on the sail from the beam (or sunlight in the case of NEA Scout) over the duration of the thrust maneuver. The propulsive maneuver is maintained by accurate understanding of the torque on the sail, which is a function of sail shape, optical properties, and mass properties, all of which apply to NEA Scout and beam propelled sails. NEA Scout uses active control of the sail attitude while trimming the solar torque, which could be used on a beamed propulsion sail if necessary. The biggest difference is that NEA Scout can correct for uncertainties in sail thrust modeling, spacecraft orbit, and target orbit throughout the flight to the target, while beamed propulsion needs accurate operation for the short duration of the beamed propulsion maneuver, making accurate understanding of the sail thrust and orbits much more critical.

Diedrich, Benjamin↗
NASA NTRS2018

Testing and Maturing a Mass Translating Mechanism for a Deep Space CubeSat

Near Earth Asteroid (NEA) Scout is a deep space satellite set to launch aboard NASA’s Exploration Mission 1. The spacecraft fits within a CubeSat standard 6U (about 300 x 200 x 100 mm) and is designed to travel 1 AU over a 2.5 year mission to observe NEA VG 1991. The spacecraft will use an 86 square meter solar sail to maneuver from lunar orbit to the NEA. One of the critical mechanisms aboard NEA Scout, the Active Mass Translator (AMT), has gone through rigorous design and test cycles since its conception in July of 2015. The AMT is a two-axis translation table required to balance the spacecraft’s center of mass (CM) and solar sail center of pressure (CP) while also trimming disturbance torque created by off-nominal sail conditions. The AMT has very limited mass and volume requirements, but is still required to deliver a large translation range—about 160 x 68 mm—at sub mm accuracy and precision. The system must accommodate and protect a shielded wire harness and coax cables during translation. Lastly, the system has been constrained to operate in complete exposure to space with limited power and data budgets for mechanical and thermal needs. The NEA Scout team has developed and carried out a rigorous test suite for the prototype and engineering development unit (EDU). These tests uncovered numerous design failures and led to many failure investigations and iteration cycles. This paper will site each discovery and discuss at length the most surprising and difficult failures to date as the NEA Scout AMT moved through functional, random vibration, thermal vacuum, harnessing, and design life verification testing. A paper was previously presented at the 43rd Aerospace Mechanisms Symposia entitled, “Development of a High Performance, Low Profile Translation Table with Wire Feedthrough for a Deep Space CubeSat”. This paper will make note of specific lessons learned from the test activities: testing ideologies for high-risk missions, thermal mitigation design for small mechanisms, non-flight qualified stepper motor accommodation, harnessing volume allocation/design, and ground testing of mechanisms developed for zero-g environments.

Few, Alex↗
NASA NTRS2014

Near-Earth Asteroids: Destinations for Human Exploration

The Near-Earth Object Human Space Flight Accessible Targets Study (NHATS) is a system that monitors the near-Earth asteroid (NEA) population to identify NEAs whose orbital characteristics may make them potential destinations for future round-trip human space flight missions. To accomplish this monitoring, Brent Barbee (GSFC) developed and automated a system that applies specialized trajectory processing to the orbits of newly discovered NEAs, and those for which we have updated orbit knowledge, obtained from the JPL Small Bodies Database (SBDB). This automated process executes daily and the results are distributed to the general public and the astronomy community. This aids in prioritizing telescope radar time allocations for obtaining crucial follow-up observations of highly accessible NEAs during the critical, because it is often fleeting, time period surrounding the time at which the NEAs are initially discovered.

NEO↗
NASA NTRSDate not supplied

Solar Sail Torque Model Characterization for the Near Earth Asteroid Scout Mission

Near Earth Asteroid Scout (NEA Scout) was a mission to test solar sail propulsion for orbital transfer from cislunar space to flyby and image an asteroid. Had it succeeded, one of the mission goals was to characterize the solar torque on the sail to ensure successful attitude control for the orbit transfer and imaging the asteroid. The simulation used to develop the flight attitude control software uses the generalized model for solar sails, a tensor equation of the forces and torques on sails of arbitrary shape. Rios-Reyes and Scheeres developed a general process to update the torque tensor coefficients using estimates of sail torque over a range of directions to the sun. Their process was adapted and implemented for the specific case of NEA Scout using spacecraft telemetry collected during sail characterization maneuvers in combination with simulation models and parameters. The NEA Scout maneuvers were limited to the operating range of the mission and constraints of the control hardware and allowed safe testing of each attitude before proceeding to the next. The NEA Scout reaction wheel speeds are used to measure accumulated momentum, while the Active Mass Translator (AMT) position is used to subtract out the torque from the center of mass crossed with the sail force and isolate the torque from only the sail shape. The process was tested by running attitude control simulations of the characterization maneuvers, generating simulated telemetry, estimating the solar torques, then using a least squares estimating the solar torque coefficients using least-squares and then performing a least-squares fit to the solar torque tensor coefficients. These estimated coefficients were tested by evaluating the solar torques under the same conditions as the simulated telemetry and comparing to the true simulated torques. Solar force model updates can be performed separately by observing the effect of the sail on the trajectory, and the torque model can be refined using those solar force updates. This process met the needs of the NEA Scout mission and can be adapted to characterize the solar torque for other missions with different sails.

solar sail↗
NASA NTRSDate not supplied

Solar Sail Torque Model Characterization for the Near Earth Asteroid Scout Mission

Near Earth Asteroid Scout (NEA Scout) was a mission to test solar sail propulsion for orbital transfer from cislunar space to flyby and image an asteroid. One of the goals of the mission was to characterize the solar torque on the sail to ensure successful attitude control for the orbit transfer and imaging the asteroid. The simulation used to develop the flight attitude control software uses the generalized model for solar sails, a tensor equation of the forces and torques on sails of arbitrary shape. Rios-Reyes and Scheeres developed a general process to update the torque tensor coefficients using estimates of sail torque over a range of directions to the sun. Their process was adapted and implemented for the specific case of NEA Scout using spacecraft telemetry collected during sail characterization maneuvers in combination with simulation models and parameters. The NEA Scout maneuvers were limited to the operating range of the mission and constraints of the control hardware and allowed safe testing of each attitude before proceeding to the next. The NEA Scout reaction wheel speeds are used to measure accumulated momentum, while the Active Mass Translator (AMT) position is used to subtract out the torque from the center of mass crossed with the sail force and isolate the torque from only the sail shape. The process was tested by running attitude control simulations of the characterization maneuvers, generating simulated telemetry, estimating the solar torques, then using a least squares estimating the solar torque coefficients using least-squares and then performing a least-squares fit to the solar torque tensor coefficients. These estimated coefficients were tested by evaluating the solar torques under the same conditions as the simulated telemetry and comparing to the true simulated torques. Solar force model updates can be performed separately by observing the effect of the sail on the trajectory, and the torque model can be refined using those solar force updates. This process met the needs of the NEA Scout mission and can be adapted to characterize the solar torque for other missions with different sails.

solar sail↗
DOE OSTI2020

Ion Gating in Nanopore Electrode Arrays with Hierarchically Organized pH-Responsive Block Copolymer Membranes

Inspired by biological ion channels, artificial nanopore-based architectures have been developed for smart ion/molecular transport control with potential applications to iontronics and energy conversion. Advances in nanofabrication technology enable simple, versatile construction methods, and post-fabrication functionalization delivers nanochannels with unique ion transport-control attributes. Here, we characterize a pH-responsive, charge-selective dual-gating block copolymer (BCP) membrane composed of polystyrene-b-poly(4-vinylpyridine) (PS 48400 -b-P4VP 21300 ), capable of self-organizing into highly ordered nanocylindrical domains. Because the PS-b-P4VP membrane exhibits pH-dependent structural transitions, it is suitable for designing intelligent pH-gated biomimetic channels, for example, exhibiting on–off transport switching at pH values near the pK a of P4VP with excellent anion permselectivity at pH < pK a . Introducing the BCP membrane onto nanopore electrode arrays (BCP@NEAs) allows the BCP to serve as a pH-responsive gate controlling ion transfer into the NEA nanopores. Such selectively transported and confined ions are detected by using a 100 nm gap dual-ring nanoelectrode structure capable of enhancing current output by efficient redox cycling with an amplification factor >10 2 . In addition, BCP@NEAs exhibit extraordinary pH-gated ion selectivity, resulting in a 3380-fold current difference between anion and cation probes at pH 3.0. Furthermore, this hierarchically organized BCP-gated NEA system can serve as a template for the development of other stimulus-responsive ion gates, for example, those based on temperature and ligand gating, thus exploiting the intrinsic advantages of NEAs, such as enhanced sensitivity based on redox cycling, which may lead to technological applications such as engineered biosensors and iontronic devices.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Multifunctional nanopore electrode array method for characterizing and manipulating single entities in attoliter-volume enclosures

Structurally regular nanopore arrays fabricated to contain independently controllable annular electrodes represent a new kind of architecture capable of electrochemically addressing small collections of matter—down to the single entity (molecule, particle, and biological cell) level. Furthermore, these nanopore electrode arrays (NEAs) can also be interrogated optically to achieve single entity spectroelectrochemistry. Larger entities such as nanoparticles and single bacterial cells are investigated by dark-field scattering and potential-controlled single-cell luminescence experiments, respectively, while NEA-confined molecules are probed by single molecule luminescence. By carrying out these experiments in arrays of identically constructed nanopores, massively parallel collections of single entities can be investigated simultaneously. The multilayer metal–insulator design of the NEAs enables highly efficient redox cycling experiments with large increases in analytical sensitivity for chemical sensing applications. NEAs may also be augmented with an additional orthogonally designed nanopore layer, such as a structured block copolymer, to achieve hierarchically organized multilayer structures with multiple stimulus-responsive transport control mechanisms. Finally, NEAs constructed with a transparent bottom layer permit optical access to the interior of the nanopore, which can result in the cutoff of far-field mode propagation, effectively trapping radiation in an ultrasmall volume inside the nanopore. Furthermore, the bottom metal layer may be used as both a working electrode and an optical cladding layer, thus, producing bifunctional electrochemical zero-mode waveguide architectures capable of carrying out spectroelectrochemical investigations down to the single molecule level.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Yarkovsky Drift Detections for 247 Near-Earth Asteroids

The Yarkovsky effect is a thermal process acting upon the orbits of small celestial bodies, which can cause these orbits to slowly expand or contract with time. The effect is subtle (〈da/dt〉∼10{sup −4} au My{sup −1} for a 1 km diameter object) and is thus generally difficult to measure. We analyzed both optical and radar astrometry for 600 Near-Earth Asteroids (NEAs) for the purpose of detecting and quantifying the Yarkovsky effect. We present 247 NEAs with measured drift rates, which is the largest published set of Yarkovsky detections. This large sample size provides an opportunity to examine the Yarkovsky effect in a statistical manner. In particular, we describe two independent population-based tests that verify the measurement of Yarkovsky orbital drift. First, we provide observational confirmation for the Yarkovsky effect’s theoretical size dependence of 1/D, where D is diameter. Second, we find that the observed ratio of negative to positive drift rates in our sample is 2.34, which, accounting for bias and sampling uncertainty, implies an actual ratio of 2.7{sub −0.7}{sup +0.3}. This ratio has a vanishingly small probability of occurring due to chance or statistical noise. The observed ratio of retrograde to prograde rotators is two times lower than the ratio expected from numerical predictions from NEA population studies and traditional assumptions about the sense of rotation of NEAs originating from various main belt escape routes. We also examine the efficiency with which solar energy is converted into orbital energy and find a median efficiency in our sample of 12%. We interpret this efficiency in terms of NEA spin and thermal properties.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS1996

Comparison of Separation Shock for Explosive and Nonexplosive Release Actuators on a Small Spacecraft Panel

Functional shock, safety, overall system costs, and emergence of new technologies, have raised concerns regarding continued use of pyrotechnics on spacecraft. NASA Headquarters-Office of Chief Engineer requested Langley Research Center (LaRC) study pyrotechnic alternatives using non-explosive actuators (NEA's), and LARC participated with Lockheed Martin Missile and Space Co. (LMMSC)-Sunnyvale, CA in objectively evaluating applicability of some NEA mechanisms to reduce small spacecraft and booster separation event shock. Comparative tests were conducted on a structural simulator using five different separation nut mechanisms, consisting of three pyrotechnics from OEA-Aerospace and Hi-Shear Technology and two NEA's from G&H Technology and Lockheed Martin Astronautics (LMA)-Denver, CO. Multiple actuations were performed with preloads up to 7000 pounds, 7000 being the comparison standard. All devices except LMA's NEA rotary flywheel-nut concept were available units with no added provisions to attenuate shock. Accelerometer measurements were recorded, reviewed, processed into Shock Response Spectra (SRS), and comparisons performed. For the standard preload, pyrotechnics produced the most severe and the G&H NEA the least severe functional shock levels. Comparing all results, the LMA concept produced the lowest levels, with preload limited to approximately 4200 pounds. Testing this concept over a range of 3000 to 4200 pounds indicated no effect of preload on shock response levels. This report presents data from these tests and the comparative results.

Lucy, M. H.↗
NASA NTRS2003

Impacts and evolution: future prospects

The discipline of astrobiology includes the dynamics of biological evolution. One of the major ways that the cosmos influences life is through the catastrophic environmental disruptions caused when comets and asteroids collide with a planet. We now recognize that such impacts have caused mass extinctions and played a major role in determining the evolution of life on Earth. The time-averaged impact flux as a function of projectile energy can be derived from lunar cratering statistics as well as the current population of near Earth asteroids (NEAs). Effects of impacts of various energies can be modeled, using data from historic impacts [such as the Cretaceous-Tertiary (KT) impactor 65 million years ago] and the observed 1994 bombardment of Jupiter by fragments of Comet Shoemaker-Levy 9. It is of particular interest to find from such models that the terrestrial environment is highly vulnerable to perturbation from impacts, so that even such a small event as the KT impact (by a projectile 10-15 km in diameter) can lead to a mass extinction. Similar considerations allow us to model the effects of still smaller (and much more likely) impacts, down to the size of the asteroid that exploded over Tunguska in 1908 (energy approximately 10 megatons). Combining the impact flux with estimates of environmental and ecological effects reveals that the greatest contemporary hazard is associated with impactors near 1 million megatons in energy (approximately 2 km in diameter for an asteroid). The current impact hazard is significant relative to other natural hazards, and arguments can be developed to illuminate a variety of public policy issues. The first priority in any plan for defense against impactors is to survey the population of Earth-crossing NEAs and project their orbits forward in time. This is the purpose of the Spaceguard Survey, which has already found more than half of the NEAs >1 km in diameter. If there is an NEA on a collision course with Earth, it can be discovered and the impact predicted with decades or more of warning. It is then possible to consider how to deflect or disrupt the NEA. Unlike other natural hazards, the impact risk can be largely eliminated, given sufficient advanced knowledge to take action against the threatening projectile.

Directed Molecular Evolution↗
NASA NTRS2004

Miniaturized multiplex label-free electronic chip for rapid nucleic acid analysis based on carbon nanotube nanoelectrode arrays

BACKGROUND: Reducing cost and time is the major concern in clinical diagnostics, particularly in molecular diagnostics. Miniaturization technologies have been recognized as promising solutions to provide low-cost microchips for diagnostics. With the recent advancement in nanotechnologies, it is possible to further improve detection sensitivity and simplify sample preparation by incorporating nanoscale elements in diagnostics devices. A fusion of micro- and nanotechnologies with biology has great potential for the development of low-cost disposable chips for rapid molecular analysis that can be carried out with simple handheld devices. APPROACH: Vertically aligned multiwalled carbon nanotubes (MWNTs) are fabricated on predeposited microelectrode pads and encapsulated in SiO2 dielectrics with only the very end exposed at the surface to form an inlaid nanoelectrode array (NEA). The NEA is used to collect the electrochemical signal associated with the target molecules binding to the probe molecules, which are covalently attached to the end of the MWNTs. CONTENT: A 3 x 3 microelectrode array is presented to demonstrate the miniaturization and multiplexing capability. A randomly distributed MWNT NEA is fabricated on each microelectrode pad. Selective functionalization of the MWNT end with a specific oligonucleotide probe and passivation of the SiO2 surface with ethylene glycol moieties are discussed. Ru(bpy)2+ -mediator-amplified guanine oxidation is used to directly measure the electrochemical signal associated with target molecules. SUMMARY: The discussed MWNT NEAs have ultrahigh sensitivity in direct electrochemical detection of guanine bases in the nucleic acid target. Fewer than approximately 1000 target nucleic acid molecules can be measured with a single microelectrode pad of approximately 20 x 20 microm2, which approaches the detection limit of laser scanners in fluorescence-based DNA microarray techniques. MWNT NEAs can be easily integrated with microelectronic circuitry and microfluidics for development of a fully automated system for rapid molecular analysis with minimum cost.

Carbon↗
NASA NTRS2010

Human Health and Performance Considerations for Exploration of Near-Earth Asteroids

This presentation will describe the human health and performance issues that are anticipated for the human exploration of near-Earth asteroids (NEA). Humans are considered a system in the design of any such deep-space exploration mission, and exploration of NEA presents unique challenges for the human system. Key factors that define the mission are those that are strongly affected by distance and duration. The most critical of these is deep-space radiation exposure without even the temporary shielding of a nearby large planetary body. The current space radiation permissible exposure limits (PEL) restrict mission duration to 3-10 months depending on age and gender of crewmembers and stage of the solar cycle. Factors that affect mission architecture include medical capability; countermeasures for bone, muscle, and cardiovascular atrophy during continuous weightlessness; restricted food supplies; and limited habitable volume. The design of a habitat that can maintain the physical and psychological health of the crew and support mission operations with limited intervention from Earth will require an integrated research and development effort by NASA s Human Research Program, engineering, and human factors groups. Limited abort and return options for an NEA mission are anticipated to have important effects on crew psychology as well as influence medical supplies and training requirements of the crew. Other important factors are those related to isolation, confinement, communication delays, autonomous operations, task design, small crew size, and even the unchanging view outside the windows for most of the mission. Geological properties of the NEA will influence design of sample handling and containment, and extravehicular activity capabilities including suit ports and tools. A robotic precursor mission that collects basic information on NEA surface properties would reduce uncertainty about these aspects of the mission as well as aid in design of mission architecture and exploration tasks.

Kundrot, Craig↗
NASA NTRS2011

Methodology and Results of the Near-Earth Object (NEO) Human Space Flight (HSF) Accessible Targets Study (NHATS)

Near-Earth Asteroids (NEAs) have been identified by the Administration as potential destinations for human explorers during the mid-2020s. Planning such ambitious missions requires selecting potentially accessible targets from the growing known population of 8,008 NEAs. NASA is therefore conducting the Near-Earth Object (NEO) Human Space Flight (HSF) Accessible Targets Study (NHATS), in which the trajectory opportunities to all known NEAs are being systematically evaluated with respect to a set of defined constraints. While the NHATS algorithms have identified hundreds of NEAs which satisfy purposely inclusive trajectory constraints, only a handful of them offer truly attractive mission opportunities in the time frame of greatest interest. In this paper we will describe the structure of the NHATS algorithms and the constraints utilized in the study, present current study results, and discuss various mission design considerations for future human space flight missions to NEAs.

Barbee, Brent W.↗
NASA NTRS2012

Human Missions to Near-Earth Asteroids: An Update on NASA's Current Status and Proposed Activities for Small Body Exploration

Over the past several years, much attention has been focused on the human exploration of near-Earth asteroids (NEAs). Two independent NASA studies examined the feasibility of sending piloted missions to NEAs, and in 2009, the Augustine Commission identified NEAs as high profile destinations for human exploration missions beyond the Earth-Moon system as part of the Flexible Path. More recently the current U.S. presidential administration directed NASA to include NEAs as destinations for future human exploration with the goal of sending astronauts to a NEA in the mid to late 2020s. This directive became part of the official National Space Policy of the United States of America as of June 28, 2010.

Abell, P. A.↗
NASA NTRS2013

Near-Earth Object Exploration and Marco Polo-R

A major goal for NASA's human spaceflight program is to send astronauts to near-Earth asteroids (NEAs) in the coming decades. Missions to NEAs would undoubtedly provide a great deal of technical and engineering data on spacecraft operations for future human space exploration while conducting in-depth scientific examinations of these primitive objects. However, prior to sending human explorers to NEAs, robotic investigations of these bodies would be required in order to maximize operational efficiency and reduce mission risk. These precursor missions to NEAs would fill crucial strategic knowledge gaps concerning their physical characteristics that are relevant for human exploration of these relatively unknown destinations. Therefore robotic investigations of NEAs, such as ESA's Marco Polo-R sample return mission to 2008 EV5, would allow NASA and its international partners to gain critical operational experience in performing complex tasks (e.g., close proximity operations, surface sample collection, etc.) under microgravity conditions at or near the surface of a potential human destination. This would provide an important synergy between the worldwide Science and Exploration communities, which will be crucial for development of future international deep space exploration architectures and has potential benefits for future exploration of other destinations beyond low-Earth orbit.

Abell, Paul↗
NASA NTRS2014

Near-Earth Asteroid Scout

Near-Earth Asteroids (NEAs) are an easily accessible object in Earth's vicinity. Detections of NEAs are expected to grow in the near future, offering increasing target opportunities. As NASA continues to refine its plans to possibly explore these small worlds with human explorers, initial reconnaissance with comparatively inexpensive robotic precursors is necessary. Obtaining and analyzing relevant data about these bodies via robotic precursors before committing a crew to visit a NEA will significantly minimize crew and mission risk, as well as maximize exploration return potential. The Marshall Space Flight Center (MSFC) and Jet Propulsion Laboratory (JPL) are jointly examining a mission concept, tentatively called 'NEA Scout,' utilizing a low-cost CubeSats platform in response to the current needs for affordable missions with exploration science value. The NEA Scout mission concept would be a secondary payload on the Space Launch System (SLS) Exploration Mission 1 (EM-1), the first planned flight of the SLS and the second un-crewed test flight of the Orion Multi-Purpose Crew Vehicle (MPCV).

McNutt, Leslie↗