Skip to main content

About this book

The Earth has limited resources while the resources in space are virtually unlimited. Further development of humanity will require going beyond our planet and exploring of extraterrestrial bodies and their resources.

This book investigates Outer Solar Systems and their prospective energy and material resources. It presents past missions and future technologies and solutions to old problems that could become reality in our life time. The book therefore is a great resource of condensed information for specialists interested in current and impending Outer Solar Systems related activities and a good starting point for space researchers, inventors, technologists and potential investors.

Table of Contents


Properties of Planetary Regolith


Chapter 1. A Survey of Pluto’s Surface Composition

Pluto was discovered less than 100 years ago (in 1930) by Clyde Tombaugh at Lowell Observatory in Flagstaff, AZ. The founder of the observatory, Percival Lowell, had initiated a systematic search of the sky to find the putative Planet X in 1905 (Tombaugh 1960).
Catherine Olkin, Will Grundy

Chapter 2. Physical Properties of Icy Materials

There is evidence that water-ice exists on a number of bodies in the solar system. As ice deposits may contain biomarkers that indicate the presence of life, or can be used as a consumable resource for future missions, confirming these observations with in-situ measurements is of great interest. Missions aiming to do this must consider how the presence of water-ice in regolith affects both the regolith’s properties and the performance of the instruments that interact with it. The properties of icy lunar and Martian regolith simulants in preparation for currently planned missions are examined in this chapter. These results can be used in future instrumentation testing and missions designed to explore other icy bodies in the solar system. The testing of icy lunar regolith simulants is summarised, before focusing on experiments demonstrating the change in properties of frozen NU-LHT-2M, a simulant of the highlands regolith found at the lunar poles, as water is added. Further tests showed a critical point of 5 ± 1% water mass content where the penetration resistance significantly increases. The addition of water to Martian regolith simulants was also examined, with the presence of salts resulting in the formation of cemented crusts under simulated Martian conditions. Additional tests with the ExoMars PSDDS demonstrated how increased internal cohesion caused by the water resulted in the failure of the instrument.
Craig Pitcher, Yang Gao

Resource, Mining, and Subsurface Access


Chapter 3. Atmospheric Mining in the Outer Solar System: Resource Capturing, Storage, and Utilization

Atmospheric mining of the outer solar system is one of the options for creating nuclear fuels, such as helium 3 .
Bryan Palaszewski

Chapter 4. Project VALKYRIE: Laser-Powered Cryobots and Other Methods for Penetrating Deep Ice on Ocean Worlds

The existence of water beneath the ice of outer Solar System moons has opened up new targets for the search for extant life, making sub-ice oceans of these bodies among the most likely places to be successful in this search.
William Stone, Bart Hogan, Vickie Siegel, John Harman, Chris Flesher, Evan Clark, Omkar Pradhan, Albin Gasiewski, Steve Howe, Troy Howe

Chapter 5. Europa Drum Sampler (EDuS)

Here we present a concept for sample acquisition and delivery on a future Europa lander, called Europa Drum Sampler (EDuS). The sampler is designed for unknown surface topography which requires the sampling system to be adaptable to variable surface features. The Europa surface could be composed of cryogenic water ice of different densities (very dense to very porous), salt, or frozen sulfuric acid. As such, the sampling system needs to be able to work with any of these materials. The fact that Europa’s surface is also covered by salt limits the use of obvious sampling systems such as a melt probe. Since local gravity is 1.3 m/s2, the maximum force the lander could provide will be significantly limited. The sampling system is therefore based on a roadheader design, used in road construction and mining.
Kris Zacny

Chapter 6. Drilling Mechanisms Using Piezoelectric Actuators Developed at Jet Propulsion Laboratory

Drilling mechanisms are widely used in many diverse fields including domestic, medical, industrial, military, geology and extraterrestrial applications (Bar-Cohen and Zacny in Drilling in Extreme Environments—Penetration and Sampling on Earth and Other Planets, Wiley—VCH, Hoboken, NJ, ISBN-10: 3527408525, ISBN-13: 9783527408528, 827 p, 2009). Generally, scientists and engineers have developed many types of drills with the majority of designs based on mechanical motion (rotary and/or percussive) of a cutting tool. These drills have been the result of the effort to deal with the challenges presented by the large variety of materials that need to be penetrated. Mechanical drills use a bit having a tip that interacts with the drilled material and applies forces over a small area to cause large shear and/or impact stresses for cutting or breaking the material. There is a wide variety of bit types that have been developed commercially, which can be readily purchased at local hardware stores. Increasingly, developers of drills for in situ exploration missions are seeking capabilities that address the complex challenges involved with extreme environments found at the planetary bodies where subsurface penetration is needed. This chapter is focused on the drilling mechanisms that are driven by piezoelectric actuators, which were developed by the authors at the Jet Propulsion Lab (JPL), Pasadena, CA. 
Yoseph Bar-Cohen, Stewart Sherrit, Mircea Badescu, Hyeong Jae Lee, Xiaoqi Bao, Zensheu Chang

Chapter 7. Ultrasonically-Assisted Penetration of Granular and Cemented Materials

Granular material can often be penetrated by the application of high-frequency vibrations. This effect may be seen in loosely packed granular material, in permafrost where the discrete grains exist in an icy matrix, and even where those grains have been compacted and cemented to form a sedimentary rock . For space applications, the vibrations may be reasonably generated by a Langevin transducer and their energy delivered to the target material by a number of different mechanisms, depending on the nature of the target and the depth or bore diameter of the desired drill campaign. The application of such vibrations is generally associated with reductions in weight-on-bit and power requirements when compared to more traditional techniques.
David Firstbrook, Patrick Harkness, Xuan Li, Ryan Timoney, Kevin Worrall

Missions and Missison Concepts


Chapter 8. Flight in the Outer Solar System and Interstellar Travel

Interstellar travel is the term used for hypothetical piloted or unpiloted travel between stars. Interstellar travel will be much more difficult than interplanetary spaceflight; the distances between the planets in the Solar System are less than 30 astronomical units (AU), whereas the distances between stars are typically hundreds of thousands of AU.
Alexander Bolonkin

Chapter 9. Triton Hopper: Exploring Neptune’s Captured Kuiper Belt Object

Neptune’s moon Triton is a fascinating object, a dynamic moon with an atmosphere, and geysers. Given the availability of volatiles (primarily nitrogen ice) on the surface a concept study was performed to see how these ices could be used as propellant to hop across the surface and explore the many different terrains of the moon. Termed Triton Hopper, the Phase 1 mission concept study was funded by the NASA Innovative Advanced Concepts (NIAC) program in 2015.
Steven R. Oleson, Geoffrey Landis

Chapter 10. Sub-ice Autonomous Underwater Vehicle Architectures for Ocean World Exploration and Life Search

Ice-covered oceans are found across the Solar System. On Earth, such environments are known to harbor life. On some Ocean Worlds such as Europa, the unique combination of an actively recycled ice shell and rocky, possibly magmatic interior may give rise to a geochemical system suitable to life and not so terribly different from the terrestrial cryosphere, where the ice may act as a suitable interface along which melt and freeze provide chemical gradients of which life can take advantage. The entry into sub-ice oceans of Ocean Worlds calls for the development of autonomous underwater vehicle (AUV) rovers to explore these water bodies. The most fruitful places to search for life will be at energy sources provided by physical and chemical gradients, which may not necessarily occur at the break-through location of a cryobot. This implies exploration using a mobile platform, and this in turn–due to extremely limited bandwidth and hours-long round-trip transmission delay–must be an autonomous platform. This forms the final step of an Ocean Worlds life search program. An intelligent underwater robotic explorer which can travel in an icecovered ocean; identify signs of biological activity; home in on, acquire, and analyze samples; and return to a docking station (the cryobot “mothership”) to upload data and recharge is a powerful tool in the search for life off Earth.
William Stone, Kristof Richmond, Chris Flesher, Bart Hogan, Vickie Siegel

Chapter 11. Titan Submarine

The conceptual design of a submarine for Saturn’s moon Titan was a funded NASA’s Innovative Advanced Concepts (NIAC) Phase 1 for 2014. The effort investigated what science a submarine for Titan’s liquid hydrocarbon ~93 K (–180 °C) seas might accomplish and what that submarine might look like. Focusing on a flagship class science system (~100 kg) it was found that a submersible platform can accomplish extensive and exciting science both above and below the surface of the Kraken Mare The submerged science includes mapping using side looking sonar, imaging and spectroscopy of the sea at all depths, as well as sampling of the sea’s bottom and shallow shoreline. While surfaced the submarine will not only sense weather conditions (including the interaction between the liquid and atmosphere) but also image the shoreline, as much as 2 km inland. This imaging requirement pushed the landing date to Titan’s next summer period (~2047) to allow for continuous lighted conditions, as well as direct-to-Earth (DTE) communication, avoiding the need for a separate relay orbiter spacecraft. Submerged and surfaced investigation are key to understanding both the hydrological cycle of Titan as well as gather hints to how life may have begun on Earth using liquid/sediment/chemical interactions. An estimated 25 Mb of data per day would be generated by the various science packages. Most of the science packages (electronics at least) can be safely kept inside the submarine pressure vessel and warmed by the isotope power system. This chapter discusses the results of Phase I as well as the plans for Phase II.
Steven R. Oleson, Jason Hartwig, Jeffrey Woytach, Michael Martini, Anthony Colozza, Robert Jones, Thomas Packard, Paul Schmitz, Amy Stalker, Ralph D. Lorenz, Michael V. Paul, Justin Walsh

Chapter 12. WindBots: A Concept for Persistent In Situ Science Explorers for Gas Giants

Visible to the naked eye, the gas giants Jupiter and Saturn have been known to astronomers since antiquity. In the modern times much was learned about them, and yet so much remains to be learned. They are made almost entirely of hydrogen and helium, they have no hard surface to land to; their low temperature atmospheres are characterized by strong winds, at least in the observed upper atmosphere. What we know about them comes from remote sensing—yet their clouds impede deeper observation through remote sensing. We also have, in a singular case, data transmitted by a robotic probe that descended through the Jovian atmosphere. We need more of these probes, to confirm the models we formed about these planets, and to discover new phenomena below their clouds. This chapter examines mission concept alternatives in which robotic craft operate in the atmospheres of gas giants, for long duration, and using energy derived from local sources. In a preferred scenario these Wind Robots (WBs), with high mobility and autonomy compared to passive balloons, would operate in the Jovian atmosphere above and below the region of clouds, between 0.3 and 10 bar, for a year-long duration mission, in strong (potentially turbulent) winds. In an example, notional mission, a WB would operate in the eyewall of the Great Red Spot, using the high wind and updrafts of the anticyclone, as well as horizontal gusts. Both naturally buoyant and winged solutions, as well as hybrids of the two, are determined possible. A Network of WBs could measure wind speeds, temperatures, and atmospheric composition simultaneously, at multiple locations.
Adrian Stoica, Virgil Adumitroaie, Marco Quadrelli, Georgios Matheou, Marcin Witek, Marco Cipolato, Marco Dolci, James Roggeveen, Kyle Petersen, Kristina Andreyeva, Hunter Hall, Benjamin Donitz, Leon Kim

Chapter 13. Enceladus Vent Explorer Concept

Enceladus Vent Explorer (EVE) is a robotic mission to enter Enceladus vents. It would send two types of modules: Surface Module (SM) and Descent Module (DM). SM is a lander that lands within a few hundred meters from the entrance of an erupting vent. After a successful landing, it deploys a single or multiple DMs. First, a DM moves to a vent and descends into it. It then performs in-situ science investigations in the vent using miniaturized instruments such as microscopic imager and a microfluidics chip. Finally, it collects samples in the vent and delivers to instruments on SM for detailed analysis. Out trade study concluded that the most robust configuration of the DM would be a limbed robot that climbs down the vent using ice screws. The ice screw is a hollow metal screw used by ice climbers for making a strong anchor on ice walls. DM would rely on a power and communication link provided by SM through a tether. Should EVE be realized, it could enable not only the direct confirmation of extraterrestrial life but also the characterization of it. Comparative study of lives on different worlds would provide clues to the secret of the genesis of life.
Masahiro Ono, Karl Mitchel, Aaron Parness, Kalind Carpenter, Saverio Iacoponi, Ellie Simonson, Aaron Curtis, Mitch Ingham, Charles Budney, Tara Estlin, Carolyn Parcheta, Renaud Detry, Jeremy Nash, Jean-Pierre de la Croix, Jessie Kawata, Kevin Hand

Chapter 14. Prospect of Exploration and Exploitation of Kuiper Belt Object Resources in the Future

The Kuiper Belt is a distant region of our solar system beginning at a solar distance of about 30 AU. By now, the discovery of several small worlds, like the dwarf planets Pluto, Makemake or Haumea, has shown that the trans-Neptunian region of the solar system is indeed more crowded than first meets the eye.
Volker Maiwald

Chapter 15. Outer Solar System—Sample Return Mission by an Unmanned Interplanetary Spaceship UNIS

The Outer Solar System (OSS) with its vast dimensions contains a large number of different objects, e.g. gas giant planets like Jupiter and Saturn, dwarf planets like Pluto, and countless comets and asteroids. If we want to utilize the natural resources of the OSS, we should bring back soil and rock samples of celestial bodies in the OSS for chemical analysis to estimate the resources of metals, water, and other useful materials in this remoted region. We have designed a preliminary concept for a sample return mission to two minor bodies in the OSS, the Jupiter Trojan asteroid (624) Hektor and the Centaur group asteroid (2060) Chiron. The spacecraft UNIS (Unmanned Interplanetary Spaceship) for this long duration mission (probably lasting some decades) would be assembled in Low Earth Orbit. To reach the targets it would need to perform several gravity assist maneuvers via planetary encounters in the Inner Solar System. After arriving at the targets a robotic lander (SPIDER) would be activated to descend to and sample the surface.
Werner Grandl, Ákos Bazsó, Andreas F. Felsenstein

Enabling Technologies


Chapter 16. Spacecraft Power System Considerations for the Far Reaches of the Solar System

Reliable and ready power is vital to any spacecraft.  Currently, two practical options exist for providing that power, harvesting energy from the Sun or heat generated from a nuclear source.  Solar photovoltaics is an excellent way to convert the Sun’s energy to electricity within the inner solar system, Mars and perhaps Jupiter if the mission is designed accordingly.  However, long term science investigations to the outer planets, which pose a harsh, dark and cold environment, are well served by nuclear based technology such as a radioisotope power system that would provide not only constant Sun-independent power, but also as important, heat generated by the long-term natural radioactive decay process of plutonium-238.  This technology can truly enable missions to the outer solar system and beyond otherwise not achievable.
Robert Cataldo

Chapter 17. Hybrid Nuclear Spacecraft for the Outer Planets

Chemical rockets are never going to allow us to exploit outer solar system resources. That is going to require massive spacecraft capable of transporting heavy loads of cargo.  It is also going to require reducing trip durations to economically viable times, and this must be done at a cost sufficiently low that resources from beyond the asteroid belt can compete with those obtainable within it.  Chemical fuels simply cannot produce the power density and specific impulse needed to meet these requirements.  Nuclear fuels can provide orders of magnitude greater power density, but conventional nuclear thermal propulsion still limits specific impulse to insufficient values.  However, a hybrid nuclear reactor can employ a fusion reaction at less than 5% of breakeven in a gas dynamic mirror thruster to generate a flux of neutrons that can drive a subcritical fission reaction in a fissile fuel, or via the thorium cycle, in which fissile U233 is bred.  The combined fusion and fission reactions can, in theory, generate specific impulse as high as several hundred thousand seconds, with continuous power levels in excess of 100 terawatts.  If achievable in practice, this would enable a ship with economically viable cargo capacity to travel under continuous acceleration to all outer solar system bodies, including distant Eris, in economically acceptable times – days or weeks – without requiring prohibitively high amounts of propellant.  But the bulk of the power would come from the fission reaction, and converting all or most of the potential fission energy to thrust presents a daunting challenge that present and foreseeable future technology may not be fully able to meet.  Nevertheless a more modest capability appears possible and could still enable high-capacity cargo ships to reach Jupiter and possibly Saturn in commercially viable times. Outer solar system resources could be tapped to meet terrestrial needs, or for use by facilities or colonies in orbit or on the Moon or Mars. But this requires that they be either uniquely obtainable from locations beyond the asteroid belt or cost competitive with terrestrial and inner solar system resources. While it may very well be that the outer solar system contains needed resources unobtainable closer to home, the more conservative assumption is that they will have to compete on cost. Distance alone does not preclude that, as current global trade in resources demonstrates.
Mark A. Stull, Ricky Tang

Chapter 18. Exploration of the Outer Solar System: Missions and Their Power Systems Exploration Missions

The outer solar system, and in particular the giant planets and their large moons, have been visited by a number of exploration missions since the early 1970s. It may not be a surprise that the number of missions targeting the different outer planets is inversely proportional to the distance to the Earth. Jupiter, the innermost of the outer plants, has been investigated by a number of flyby missions, orbiters, and even an atmospheric probe. Uranus and Neptune, the two outermost planets, have only been investigated by a single flyby mission up to date. The intention of this chapter is to provide a brief overview of the exploration missions launched to the outer solar system up to date. In this, a special emphasis is put on discussing the power systems applied with the different missions and spacecraft. Environmental conditions and mission plans do not allow the variety of power system options and designs we have seen with Lunar and Martian exploration. It is nevertheless interesting to have a look at the different power systems, and to see their evolution over time.
Simon D. Fraser

Chapter 19. Multi-rendezvous Solar Electric Propulsion Mission Opportunities to Jupiter Trojans

Jupiter Trojans are a group of small bodies (sized rarely up to some hundred kilometers), which gather at the L4 and L5 Libration Points of the Jupiter–Sun system. Max Wolfe discovered the first Trojan asteroid in 1906 and named it Archilles and by that coined the term of Jupiter Trojans, as figures from the Trojan epos became namesakes for subsequent discoveries in that region of the solar system (Jewitt et al. in Jupiter’s outer satellites and Trojans, Jupiter—the planet, satellites and mangetosphere. Cambridge Planetary Science. Cambridge University Press, Cambridge, 2004).
Volker Maiwald

Business Cases for Resource Utilisation


Chapter 20. Implausible, Yet Intriguing: Business in the Outer Solar System

The possibilities of future business opportunities that might exist within the outer solar system are explored. Fictional accounts of development within space are used to provide context between imagined paths of exploration and what is more likely within the foreseeable future. Additional observations as to the nature and extent of how business might develop are discussed. Although business creation within the realm of the outer solar system is likely to remain a distant possibility, it is not without terrestrial precedents. It is also probable that business opportunities would occur at a pace faster than expected if either the resources discovered among the planets and moons proved to be of greater value than anticipated or if technology made exploitation less difficult and more cost effective. It is not if but when and how the resources of the outer solar system will be utilized in the future. In the near-term, business among the outer solar system will continue to be implausible until both opportunity and technology change significantly and catch up with the intriguing vision set forth by science fiction and business visionaries.
Mike H. Ryan, Ida Kutschera

Chapter 21. Sources of Energy in the Outer Solar System

Fusion power is useful energy generated by nuclear fusion reactions. In this kind of reaction, two light atomic nuclei fuse together to form a heavier nucleus and release energy. The largest current nuclear fusion experiment, JET, has resulted in fusion power production somewhat larger than the power put into the plasma, maintained for a few seconds. In June 2005, the construction of the experimental reactor ITER, designed to produce several times more fusion power than the power into it generating the plasma over many minutes, was announced. The unrealized production of net electrical power from fusion machines is planned for the next generation experiment after ITER.
Alexander Bolonkin


Additional information