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Lunar and Meteorite Sample Education Disk Program - Space Rocks for Classrooms, Museums, Science Centers, and Libraries

NASA is eager for students and the public to experience lunar Apollo samples and meteorites first hand. Lunar rocks and soil, embedded in Lucite disks, are available for educators to use in their classrooms, museums, science centers, and public libraries for education activities and display. The sample education disks are valuable tools for engaging students in the exploration of the Solar System. Scientific research conducted on the Apollo rocks reveals the early history of our Earth-Moon system and meteorites reveal much of the history of the early solar system. The rocks help educators make the connections to this ancient history of our planet and solar system and the basic processes accretion, differentiation, impact and volcanism. With these samples, educators in museums, science centers, libraries, and classrooms can help students and the public understand the key questions pursued by many NASA planetary missions. The Office of the Curator at Johnson Space Center is in the process of reorganizing and renewing the Lunar and Meteorite Sample Education Disk Program to increase reach, security and accountability. The new program expands the reach of these exciting extraterrestrial rocks through increased access to training and educator borrowing. One of the expanded opportunities is that trained certified educators from science centers, museums, and libraries may now borrow the extraterrestrial rock samples. Previously the loan program was only open to classroom educators so the expansion will increase the public access to the samples and allow educators to make the critical connections to the exciting exploration missions taking place in our solar system. Each Lunar Disk contains three lunar rocks and three regolith soils embedded in Lucite. The anorthosite sample is a part of the magma ocean formed on the surface of Moon in the early melting period, the basalt is part of the extensive lunar mare lava flows, and the breccias sample is an important example of the violent impact history of the Moon. The disks also include two regolith soils and orange glass from a pyroclastic deposit. Each Meteorite Disk contains two ordinary chondrites, one carbonaceous chondrite, one iron, one stony iron, and one achondrite. These samples will help educators share the early history of the solar system with students and the public. Educators may borrow either lunar or meteorite disks and the accompanying education materials through the Johnson Space Center Curatorial Office. In trainings provided by the NASA Aerospace Education Services Program specialists, educators certified to borrow the disk learn about education resources, the proper use of the samples, and the special security for care and shipping of the disks. The Lunar and Meteorite Sample Education Disk Program will take NASA exploration to more people. Getting Space Rocks out to the public and inspiring the public about new space exploration is the focus of the NASA disk loan program.

Allen, Jaclyn↗

Exploration planning in the context of human exploration and development of the Moon

It is widely believed that the next step beyond low Earth orbit in attaining the United States' stated goal of 'Expanding human presence beyond the Earth' should be to reestablish a lunar capability, building on the Apollo program, and preparing the way for eventual human missions to Mars. The Moon offers important questions in planetary and Earth science, can provide a unique platform for making astronomical observations of high resolution and sensitivity, and can be in the development path for unlocking resources of the inner solar system to support space activities and return benefits to Earth. NASA's Office of Exploration has undertaken the planning of future lunar exploration missions with the assistance of the Solar System Exploration Division in matters dealing with the quality of scientific data and the manner in which it will be made available to the scientific community. The initial elements of the proposed program include the Lunar Scout missions, which consist of two small identical spacecraft in polar orbit around the Moon, which can accomplish most of the objectives associated with previous proposals for Lunar Polar Orbiters. These missions would be followed by 'Artemis' landers, capable of emplacing up to 200 kg payloads anywhere on the Moon. In addition, the exploration program must incorporate data obtained from other missions, including the Galileo lunar flybys, the Clementine high orbital observations, and Japanese penetrator missions. In the past year, a rather detailed plan for a 'First Lunar Outpost (FLO)' which would place 4 astronauts on the lunar surface for 45 days has been developed as a possible initial step of a renewed human exploration program. In the coming year, the FLO concept will be reviewed and evolved to become more highly integrated with planning for the initial human exploration of Mars, which could come perhaps 5 years after the reestablishment of lunar capability. Both programs could benefit from the common development of systems and subsystems, where that is sensible from a performance perspective.

Duke, Michael B.↗

Potential Applications for Radioisotope Power Systems in Support of Human Exploration Missions

Radioisotope power systems (RPS) for space applications have powered over 27 U.S. space systems, starting with Transit 4A and 4B in 1961, and more recently with the successful landing of the Mars Science Laboratory rover Curiosity in August 2012. RPS enable missions with destinations far from the Sun with faint solar flux, on planetary surfaces with dense or dusty atmospheres, and at places with long eclipse periods where solar array sizes and energy storage mass become impractical. RPS could also provide an enabling capability in support of human exploration activities. It is envisioned that with the higher power needs of most human mission concepts, a high efficiency thermal-to-electric technology would be required such as the Advanced Stirling Radioisotope generator (ASRG). The ASRG should be capable of a four-fold improvement in efficiency over traditional thermoelectric RPS. While it may be impractical to use RPS as a main power source, many other applications could be considered, such as crewed pressurized rovers, in-situ resource production of propellants, back-up habitat power, drilling, any mobile or remote activity from the main base habitat, etc. This paper will identify potential applications and provide concepts that could be a practical extension of the current ASRG design in providing for robust and flexible use of RPS on human exploration missions.

Cataldo, Robert L.↗

Horizons and Opportunities in Lunar Sample Science

The Moon is the cornerstone of planetary science. Lunar sample studies were fundamental in developing an understanding of the early evolution and continued development of planetary bodies, and have led to major revisions in understanding of processes for the accumulation of planetesimals and the formation of planets. Studies of lunar samples have increased an understanding of impact cratering, meteoroid and micrometeoroid fluxes, the interaction of planetary surfaces with radiations and particles, and even the history of the Sun. The lunar sample research program was especially productive, but by no means have all the important answers been determined; continued study of lunar samples will further illuminate the shadows of our knowledge about the solar system. Further, the treasures returned through the Apollo program provide information that is required for a return to the Moon, beginning with new exploration (Lunar Geoscience Observer (LGO)), followed by intensive study (new sample return missions), and eventually culminating in a lunar base and lunar resource utilization. The few years during and following Apollo were a hectic time for lunar science. Since then, considerable maturation of the science and distinct changes in the mode of operation have developed. Funding (and hence the number of investigators) has naturally declined. Studies have become far more problem-oriented than descriptive. Many sample investigators have shifted their sights away from planetary evolution, for which the Moon holds considerable information, toward processes and materials in the pre-planetary solar nebula, for which the Moon has no direct evidence. Nonetheless, unique scientific opportunities are still supplied by the samples returned from the Apollo and Luna missions and by lunar meteorites. These 382 kg of samples constitute a priceless resource that still has enormous scientific potential. Continued interaction between NASA and the scientific community, especially through the advice of groups such as the Lunar and Planetary Sample Team (LAPST), is essential in maintaining the current level of excellence of the program. LAPST has reviewed its role, the role of the sample research community, and the perceived role of future researchers over the next decade in ensuring the effective use of lunar sample studies in space exploration and exploitation. The review encompasses: (I) lunar sample science; (2) lunar materials applications; (3) lunar sample studies and their relation to future space missions; and (4) lunar sample curation. Plans in all four areas are summarized in this document.

Source record↗

Mars Observer Mission Operations

Mars Observer, planned for launch in September 1992, will be the first deep space planetary mission to fully utilize a distributed operations concept for science instrument control. In addition, several of the other concepts proposed by the Mission Operations and Information Systems Subcommittee of the Solar System Exploration Committee have been adopted for the purpose of improving the efficiency and reducing the costs of Deep Space Mission Operations.

Mckinley, Edward L.↗

Direct UV/Optical Imaging of Stellar Surfaces: The Stellar Imager (SI) Vision Mission

The Stellar Imager (SI) is a UV/optical, space-based interferometer designed to enable 0.1 milli-arcsecond (mas) spectral imaging of stellar surfaces and, via asteroseismology, stellar interiors and of the Universe in general. SI's science focuses on the role of magnetism in the Universe, particularly on magnetic activity on the surfaces of stars like the Sun. SI's prime goal is to enable long-term forecasting of solar activity and the space weather that it drives, in support of the Living with a Star program in the Exploration Era. SI will also revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magneto-hydrodynamically controlled processes in thc Universe. SI is a "Flagship and Landmark Discovery Mission" in the 2005 Sun Solar System Connection (SSSC) Roadmap and a candidate for a "Pathways to Life Observatory" in the Exploration of the Universe Division (EUD) Roadmap. We discuss herein the science goals of the SI Mission, a mission architecture that could meet those goals, and the technologies needed to enable this mission. Additional information on SI can be found at: http://hires.gsfc.nasa.gov/si/.

Carpenter, Kenneth G.↗

Small Stirling Technology Exploration Power for Future Space Science Missions

High efficiency dynamic Radioisotope Power Systems (RPS) could be mission enabling for low power space applications such as small probes, landers rovers, and communication repeaters. These applications would contain science instruments and be distributed across planetary surfaces or near objects of interest where solar flux is insufficient for using solar cells. Small RPS could be used to provide power for sensing radiation, temperature, pressure, seismic activity, and other measurements of interest to planetary scientists. Small RPS would use fractional versions of the General Purpose Heat Source (GPHS) or Light Weight Radioisotope Heater Units (LWRHU), to heat power conversion technologies. Dynamic power systems are capable of three to four times higher conversion efficiency compared to static power conversion technologies, and would provide an equal amount of power using less fuel or more power using an equal amount of fuel. Providing spacecraft with more power could decrease duty cycling of basic functions and, therefore, increase the quality and abundance of science data. NASA GRC is developing a low power dynamic RPS that would convert heat from multiple LWRHU to one watt of usable direct current electric power for spacecraft instrumentation and communication. The power system could be used to charge batteries or capacitors for higher power burst usage. The initial design, called Small Stirling Technology Exploration Power (smallSTEP), is around 3 kg, 11 cm diameter X 32 cm long, and converts 8 watts of heat to one watt of electricity using a Stirling convertor. This low power conversion system represents a new class of RPS with power levels two orders of magnitude lower than prototypes currently being developed for space applications under NASA contracts. Development of the 1-watt RPS includes maturation of convertor and controller designs, performance evaluation of an evacuated metal foil insulation, and development of system interfaces. Initial demonstration of the subsystems has been completed in a laboratory environment and a higher fidelity system is being pursued for demonstration in relevant environments for use on small spacecraft needed to carry out future space science missions.

Wilson, Scott D.↗

Small Spacecraft for Planetary Atmospheric, Surface, and Interior Structure Using Radio Links

Scientific studies using spacecraft radio links have been conducted on almost every Solar System exploration mission in the past five decades and have led to numerous discoveries. Radio Science experiments have elucidated the thermal history of the Moon from high resolution gravitational field measurements, unveiled the interiors of Titan, Enceladus, Mercury, Phobos, Vesta and Ceres providing key evidence for identifying subsurface oceans on icy moons; sounded Titan, Saturn, and Pluto’s atmospheres, and refined models for the atmospheres, surfaces, and interior structure of Mars and Venus. A Juno experiment is in progress measuring the gravitational field of Jupiter to reveal its interior structures, as did a similar recent Cassini experiment with Saturn. Experiments at Mercury, the Jovian system, and other targets, are in development or planning phases. Over the next 30 years, significant advances in radio and laser link-science technologies, including nearly one order of magnitude improvement achievable in range-rate and range accuracy, could enable many new scientific breakthroughs. Future exploration concepts in many cases focus on applications of small spacecraft and can include spacecraft constellations for studies of atmospheric dynamics, interior structures, and surface properties. A set of science-enabling radio link technologies specific to small spacecraft instrumentation on future solar system missions are under study and development. Examples include field tests of radio scattering to determine soil properties, smallsat constellations for dense geographic and temporal atmospheric probing, small science-quality software-defined transponders, miniature ultra-stable oscillators, and advanced radio-metric calibrations at the Deep Space Network. This paper describes many of these technologies and their scientific applications.

Elliott, Harvey↗

A bibliography of planetary geology principal investigators and their associates, 1982 - 1983

This bibliography cites recent publications by principal investigators and their associates, supported through NASA's Office of Space Science and Applications, Earth and Planetary Exploration Division, Planetary Geology Program. It serves as a companion piece to NASA TM-85127, ""Reports of Planetary Programs, 1982". Entries are listed under the following subject areas: solar system, comets, asteroids, meteorites and small bodies; geologic mapping, geomorphology, and stratigraphy; structure, tectonics, and planetary and satellite evolutions; impact craters; volcanism; fluvial, mass wasting, glacial and preglacial studies; Eolian and Arid climate studies; regolith, volatiles, atmosphere, and climate, radar; remote sensing and photometric studies; and cartography, photogrammetry, geodesy, and altimetry. An author index is provided.

Plescia, J. B.↗

Small Stirling Technology Exploration Power for Future Space Science Missions

High efficiency dynamic Radioisotope Power Systems (RPS) could be mission enabling for low power space applications such as small probes, landers rovers, and communication repeaters. These applications would contain science instruments and be distributed across planetary surfaces or near objects of interest where solar flux is insufficient for using solar cells. Small RPS could be used to provide power for sensing radiation, temperature, pressure, seismic activity, and other measurements of interest to planetary scientists. Small RPS would use fractional versions of the General Purpose Heat Source (GPHS) or Light Weight Radioisotope Heater Units (LWRHU), to heat power conversion technologies. Dynamic power systems are capable of three to four times higher conversion efficiency compared to static power conversion technologies, and would provide an equal amount of power using less fuel or more power using an equal amount of fuel. Providing spacecraft with more power could decrease duty cycling of basic functions and, therefore, increase the quality and abundance of science data. NASA Glenn Research Center (GRC) is developing a low power dynamic RPS that would convert heat from multiple LWRHU to one watt of usable direct current electric power for spacecraft instrumentation and communication. The power system could be used to charge batteries or capacitors for higher power burst usage. The initial design, called Small Stirling Technology Exploration Power (smallSTEP), is around 3 kg, 11 cm diameter X 32 cm long, and converts 8 watts of heat to one watt of electricity using a Stirling convertor. This low power conversion system represents a new class of RPS with power levels two orders of magnitude lower than prototypes currently being developed for space applications under NASA contracts. Development of the 1-watt RPS includes maturation of convertor and controller designs, performance evaluation of an evacuated metal foil insulation, and development of system interfaces. Initial demonstration of the subsystems has been completed in a laboratory environment and a higher fidelity system is being pursued for demonstration in relevant environments for use on small spacecraft needed to carry out future space science missions.

Wilson, Scott↗

Advanced planetary studies

Results of planetary advanced studies and planning support provided by Science Applications, Inc. staff members to Earth and Planetary Exploration Division, OSSA/NASA, for the period 1 February 1981 to 30 April 1982 are summarized. The scope of analyses includes cost estimation, planetary missions performance, solar system exploration committee support, Mars program planning, Galilean satellite mission concepts, and advanced propulsion data base. The work covers 80 man-months of research. Study reports and related publications are included in a bibliography section.

Source record↗

Pluto Express - Out of the Darkness

Pluto, discovered in 1930, is the largest of a class of primordial bodies at the edge of our solar system that have comet-like properties and remain relatively unmodified by warming from the sun. It is the only planet in the solar system not explored via robotic spacecraft. This lecture discusses the status of the Pluto Express preproject (science objectives, etc.), and its telecommunication subsystem.

Pluto Pluto Express Planetary Exploration Spacecra↗

Astro-biological Exploration of Ocean Worlds, Enabled by an RPS Inside a Pressure Vessel

Exploring Ocean and Ice Worlds could help us to understand the origin and evolution of life in the universe. In our solar system we have identified six Ocean and Ice Worlds, namely Earth, Europa, Ganymede, Callisto, Enceladus, and Titan. Other potential targets include Dione, Triton, and Pluto. As documented in the Planetary Decadal Survey [1] and the NASA Roadmap to Ocean Worlds [2], these worlds are compelling science destinations, with oceans situated below their tens of kilometers thick ice shells. To reach them we need a new exploration paradigm with novel technological solutions. Key technological challenges revolve around the power for the probe and for melting, as well as protecting the payload against the extreme environments, including high pressure, low temperature, corrosion, and radiation. Far away from the Sun, and melted into the ice, we may only rely on long-lived internal power generation. Radioisotope Power Systems (RPS) with either static or dynamic conversion, utilizing the heat of decaying Plutonium-238, could be good candidates. We need suitable payloads that are protected and could survive the extreme environments, as well as enabling power and thermal systems for melting through the ice shield and to swim in the ocean below the ice. RPS could support the probe’s instruments and sub-systems, as well as provide a heat source for melting the ice while keeping the components at operating temperatures. Mitigating the external pressure while immersing inside the ice shell, and in the ocean, would require a new RPS design that operates inside a Pressure Vessel. In our paper, we will discuss general mission architecture trades and the sizing of a next generation RPS housed in a pressure vessel, broadly applicable to any of the Ocean Worlds satellites of interest. Through a technology focused approach, we address interconnected design and mission architecture aspects, including considerations for: the RPS and the Pressure Vessel; extreme environmental constraints; g-load tolerance; power and thermal systems sizing for science measurements; spacecraft operations through all mission phases; subsurface mobility; and planetary protection. The findings will inform the science community on instrument accommodation possibilities; the mission planning community on possible mission concepts; and the RPS development community on the science driven technology considerations.

Donitz, Benjamin P.↗

Two-Dimensional Transport Studies for the Composition and Structure of the Io Plasma Torus

The overall objective of this project is to investigate the roles of local and spatially extended plasma sources created by Io, plasma torus chemistry, and plasma convective and diffusive transport in producing the long-lived S(+), S(++) and O(+) radial ribbon structures of the plasma torus, their System III longitude and local-time asymmetries, their energy sources and their possible time variability. To accomplish this objective, two-dimensional [radial (L) and System III longitude] plasma transport equations for the flux-tube plasma content and energy content will be solved that include the convective motions for both the east-west electric field and co-rotational velocity-lag profile near Io s orbit, radial diffusion, and the spacetime dependent flux-tube production and loss created by both neutral-plasma and plasma-ion reaction chemistry in the plasma torus. For neutral-plasma chemistry, the project will for the first time undertake the calculation of realistic three-dimensional, spatially-extended, and time-varying contributions to the flux-tube ion-production and loss that are produced by Io's corona and extended neutral clouds. The unknown two-dimensional spatial nature of diffusion in the plasma transport will be isolated and better defined in the investigation by the collective consideration of the foregoing different physical processes. For energy transport, the energy flow from hot pickup ions (and a new electron source) to thermal ions and electrons will be included in investigating the System III longitude and local-time temperature asymmetries in the plasma torus. The research is central to the scope of the NASA Sun-Earth Connection Roadmap in Quest II Campaign 4 "Comparative Planetary Space Environments" by addressing key questions for understanding the magnetosphere of planets with high rotation rates and large internal plasma sources and, in addition, is of considerable importance to the NASA Solar System Exploration Science Theme. In this regard, Jupiter is the most extreme example with its rapid rotation and with its inner Galilean satellite Io providing the dominant plasma source for the magnetosphere.

Smyth, William H.↗

The MASSE Project: Applications of Biotechnology for Planetary Exploration

Automated life-detection experiments for solar system exploration have been previously. proposed and used onboard the. Viking, Mars lander,s, although. with ambiguous results. The recent advances in biotechnology such as biosensors, protein microarrays, and microfluidics alongside increased. knowledge in biomarker science have led to vastly improved sophistication and sensitivity for a new approach in life detection. The MASSE project has taken the challenge of integrating all of this knowledge into a new generation of interplanetary flight instrumentation for the main purpose.ot combining several mutually. confirming tests for life, organic/microbial contamination, prebiotic and abiotic chemicals into a small low powered instrument. Although the primary goal is interplanetary exploration, several terrestrial applications have become apparent specifically in point-of-care medical technology, bio-warfare, environmental sensing and microbial monitoring of manned space-flight vehicles.

Lynch, Kennda↗

Space Launch System Payload Stage Capability for Ultra-High Characteristic Energy Missions

The Space Launch System (SLS) vehicle is NASA’s cornerstone capability for a new era of human and robotic exploration of deep space. The unrivalled performance of SLS provides the capability to launch the first woman and next man to walk on the lunar surface and to support development of a sustained human presence in cislunar space, and ultimately human missions to Mars. As an evolvable capability with unique launch performance, the opportunities enabled by SLS also include game-changing benefits for science missions, including probes to the outer solar system and beyond. For the last two years, the SLS Program has worked with the Interstellar Probe team at the Johns Hopkins University Applied Physics Laboratory(APL) to provide data that describe how SLS could support a mission that would break through the boundary of the heliosphere and into pristine interstellar space only a decade after launch, enabling earlier science return and greatly increasing spacecraft life in the interstellar medium. In record-breaking time, the ISP as launched on SLS may answer questions raised by the extended mission of NASA’s Voyager spacecraft. While SLS and its efficient Exploration Upper Stage (EUS) offer benefits for exploration of the outer planets, adding one or more additional stages to this architecture makes it even more capable for missions beyond our solar system, offering more realistically appealing flight times that would allow the mission scientists to reap the rewards of exploration. During the time the SLS Program has been working with the Interstellar Probe team, it has identified an expedited path to the Block 2 capability planned for the Interstellar Probe mission, and further matured performance numbers for diverse multi-stage configurations using a combination of commercially available liquid hydrogen (LH2)/liquid oxygen (LOX) upper stages and solid motor kick stages. That work has demonstrated the SLS payload stage capability provides significant benefits and opens trade space for multiple missions in consideration during planning for the next Planetary Science and Astrobiology Decadal Survey. This presentation details the significant benefits SLS can provides for very high characteristic (C3) energy missions by coupling the capabilities of SLS to current commercial rocket propulsion stage systems. These capabilities are explored specifically in the context of an Interstellar Probe architecture in which a small, capable science probe, coupled with carefully tailored mission design trajectories, could be used to explore the outer solar system and the interstellar medium. The presentation will also address the operational logistics of integrating such a mission, explaining the options available for “non-standard” SLS payloads, including processing those with radioisotope power generators or additional propulsion stages. An SLS system overview and capabilities will be presented, along with vehicle configuration and orbit performance capability studies, explaining how SLS is enabling for a variety of high-energy science mission profiles, including launching an exploratory probe bound for interstellar space only a decade after launch.

Rob Stough↗

Definition phase of Grand Tour missions/radio science investigations study for outer planets missions

Scientific instrumentation for satellite communication and radio tracking systems in the outer planet exploration mission is discussed. Mission planning considers observations of planetary and satellite-masses, -atmospheres, -magnetic fields, -surfaces, -gravitational fields, solar wind composition, planetary radio emissions, and tests of general relativity in time delay and ray bending experiments.

Tyler, G. L.↗

Solar and Drag Sail Propulsion: From Theory to Mission Implementation

Solar and drag sail technology is entering the mainstream for space propulsion applications within NASA and around the world. Solar sails derive propulsion by reflecting sunlight from a large, mirror- like sail made of a lightweight, reflective material. The continuous sunlight pressure provides efficient primary propulsion, without the expenditure of propellant or any other consumable, allowing for very high V maneuvers and long-duration deep space exploration. Drag sails increase the aerodynamic drag on Low Earth Orbit (LEO) spacecraft, providing a lightweight and relatively inexpensive approach for end-of-life deorbit and reentry. Since NASA began investing in the technology in the late 1990's, significant progress has been made toward their demonstration and implementation in space. NASA's Marshall Space Flight Center (MSFC) managed the development and testing of two different 20-m solar sail systems and rigorously tested them under simulated space conditions in the Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. One of these systems, developed by L'Garde, Inc., is planned for flight in 2015. Called Sunjammer, the 38m sailcraft will unfurl in deep space and demonstrate solar sail propulsion and navigation as it flies to Earth-Sun L1. In the Flight Center (MSFC) managed the development and testing of two different 20-m solar sail systems and rigorously tested them under simulated space conditions in the Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. One of these systems, developed by L'Garde, Inc., is planned for flight in 2015. Called Sunjammer, the 38m sailcraft will unfurl in deep space and demonstrate solar sail propulsion and navigation as it flies to Earth-Sun L1. In the interim, NASA MSFC funded the NanoSail-D, a subscale drag sail system designed for small spacecraft applications. The NanoSail-D flew aboard the Fast Affordable Science and Technology SATellite (FASTSAT) in 2010, also developed by MSFC, and began its mission after it was ejected from the FASTSAT into Earth orbit, where it remained for several weeks before deorbiting as planned. NASA recently selected two small satellite missions for study as part of the Advanced Exploration Systems (AES) Program, both of which will use solar sails to enable their scientific objectives. Lunar Flashlight, managed by JPL, will search for and map volatiles in permanently shadowed Lunar craters using a solar sail as a gigantic mirror to steer sunlight into the shaded craters. The Near Earth Asteroid (NEA) Scout mission will use the sail as primary propulsion allowing it to survey and image one or more NEA's of interests for possible future human exploration. Both are being studied for possible launch in 2017. The Planetary Society's privately funded LightSail-A and -B cubesat-class spacecraft are nearly complete and scheduled for launch in 2015 and 2016, respectively. MMA Design launched their DragNet deorbit system in November 2013, which will deploy from the STPSat-3 spacecraft as an end of life deorbit system. The University of Surrey is building a suite of cubesat class drag and solar sail systems that will be launched beginning in 2015. As the technology matures, solar sails will increasingly be used to enable science and exploration missions that are currently impossible or prohibitively expensive using traditional chemical and electric rockets. For example, the NASA Heliophysics Decadal Survey identifies no less than three such missions for possible flight before the mid-2020's. Solar and drag sail propulsion technology is no longer merely an interesting theoretical possibility; it has been demonstrated in space and is now a critical technology for science and solar system exploration.

Johnson, Les↗