IRG 2021 Posters Here are abstracts of the posters that have been accepted for display at the 7th Interstellar Symposium. The MILO Space Science Institute: Demonstrating a New Paradigm for Deep Space Science Missions The MILO Space Science Institute: Demonstrating a New Paradigm for Deep Space Science Missions Author: Jim Bell Description: The MILO Space Science Institute is a non-profit deep space science mission collaboration formed in 2018 between Arizona State University and Lockheed Martin. The primary goals of MILO are: (1) Enable collaboration in deep space science missions by a consortium of domestic and international partners; (2) Provide affordable access to deep space science missions via a member-based cost-share model and leveraging lower cost mission concepts; and (3) Provide hands-on experience for members, helping to train the next generation of scientists and engineers by offering workforce development, technology demonstrations, and advancement of scientific discoveries. Methods: MILO is planning two SmallSat missions and one lunar surface mission as initial pathfinder and proof-of-concept demonstrations. The Smallsat missions, NEOShare and Apophis Pathfinder, are designed to provide new scientific and Planetary Defense knowledge about small Near-Earth Objects (NEOs). NEOShare would deploy six SmallSats to perform close flybys of up to eight NEOs as they pass close to the Earth, substantially expanding the diversity of NEOs that have been characterized by spacecraft. Apophis Pathfinder would consist of two SmallSats that perform a close flyby of Potentially Hazardous Object (99942) Apophis several years before its extremely close Earth encounter in 2029. This mission would provide initial reconnaissance data that could help to inform and optimize other missions being designed to encounter that asteroid before, during, and after its 2029 Earth flyby. Both NEO missions would be equipped with dedicated propulsion, communications, power, and other critical subsystems, and include scientific payloads consisting of cameras, spectrometers, or other high-heritage SmallSat instrumentation. The lunar surface mission would provide members with the ability to fly payloads on a Lockheed Commercial Lunar Payload Services lander, tapping into the lander’s power, data, and telecommunications systems to relay results back to Earth. Conclusions: There has been substantial international interest in MILO and a number of agreements for member involvement have been signed with universities, space agencies, and commercial space companies. Pertinent to this Symposium: While our focus has been on solar system exploration, the MILO concept could easily be extended to a consortium of members interested in conducting science-driven interstellar exploration as well. Update 2021-2100: An Interstellar University in the Ad Astra State Update 2021-2100: An Interstellar University in the Ad Astra State Author: Steve Durst Background: An Interstellar University (IU) in Kansas is now advancing as 21st Century aspiration, having been proposed at the 6th Interstellar Symposium 2019 November 10-14, Wichita, in the State with official motto “Ad Astra Per Aspera”– To the Stars Through Difficulties. IU progress made in 2020, pandemic difficulties notwithstanding, was mostly online, with 9 or 10 confirmations of interest from Symposium 6 distinguished associates for IU meetings at Galaxy Forum Kansas at the Cosmosphere in Hutchinson set for August 8, then postponed and held virtually October 24. Dr. Gerald Jackson and Steve Durst presented on Interstellar matters. The Interstellar Research Group in 2020-2021 is remarkable and dynamic with IRG transforming from TVIW and highly productive with Database Update, Proceedings from 6th IS, Annual Scholarships, and preparing, organizing for 7th Interstellar Symposium in Tucson AZ, September 25-27. Objective: In the 21st Century, the rise of an Interstellar University to advance astronautical, astrophysical, and interstellar research, knowledge, and development of unlimited dimensions is an enterprise that would benefit all Humanity, America, and of course Kansas – Mid-way USA, the breadbasket and heartland, and Ad Astra State. Methods– 2021 Preparations for IU realization include networking and organizing April 21-24 in Wichita, the Cosmosphere, and State Capitol Topeka on Ad Astra Kansas Day; Galaxy Forum Kansas 2021 in August with IU collaborative in-person and online meetings; continued outreach and interaction with Kansas universities such as Wichita State, Washburn, KU, KSU, Emporia State. Results: Growing interstellar awareness and activity, stimulated in part by appropriate Proclamation from the Kansas State Governor and other statewide public advocacy, should be demonstrable; IU academic class formation and instructor identification may proceed with reference to the almost 40 “Interstellar R&D” features on Observation, Communication, and Transportation published bi-annually since 2001 in Ad Astra Kansas News. Official launch of the Interstellar University on January 29, 2022, would be timely. Conclusions: The 2020s, with Ad Astra Kansas networking, IRG Interstellar Symposiums, JWST, international Mars activities and the cislunar superhighway, should witness initiating and sustained development of an Interstellar University in Kansas and likely other Interstellar / Interglobal education citadels. Kreutz Comets are Ultra-Fast Moving Objects – Can This Motion Be Exploited? Kreutz Comets are Ultra-Fast Moving Objects – Can This Motion Be Exploited? Author: William Gardiner Description: We require a well understood means to transport us to distant starts in less than a lifetime. Our objective is to determine whether the Kreutz group of sun-grazing comets represent a material transport process that can be emulated. The Kreutz comets typically move through the solar system at 0.2% of lightspeed, 480-600 km/sec (1.3 million mph). This allows a typical Kreutz comet to cross the distance between Mars and Earth in as little as a week. As there have been some 3000 such objects observed by the SOHO sun-observing probe between 1996 and 2010, there is an apparent regular, repeatable, discoverable process here that has escaped our investigation. Our method is to examine the electrochemical nature of these plasma engulfed objects to gain insight into the manner of their apparent movement using the spectrographic information archived for these objects, as well as from data collected at comet 67P with their onboard Langmuir probe and apply the model of chemist Dr. Franklin Anariba describing the electrochemical interaction between comets and their environment within the heliosphere. The expected results will provide a design principle for a spacecraft that literally “couples to space,” to use a phrase offered by Marc Millis during his time with the NASA Breakthrough Physics Propulsion Project. Our conclusion will be that space is not an empty plenum, and the material manifestation of Marc’s original concept will be to predict the voltage gradients of these fast moving objects, or perhaps they are plasmoids, that essentially emulate the behavior of a load on a well-designed LRC circuit, but which also participate in the orbital behavior of all celestial objects in the observable universe. If Loud Aliens Explain Human Earliness, Quiet Aliens Are Also Rare If Loud Aliens Explain Human Earliness, Quiet Aliens Are Also Rare Authors: Robin Hanson, Daniel Martin, Calvin McCarter, and Jonathan Paulson Background: The Drake equation has been used to estimate the density of hard-to-see “quiet” aliens. We instead estimate easy-to-see “loud” aliens. Objective: To estimate and find implications of a model of “grabby” civilizations (GC), who expand fast and long, and change their volumes’ appearances. To motivate this model by estimating human earliness. Methods: Using a model of star formation, habitability, and advanced life arrival via hard steps, we estimate that humans are very early, unless GCs set a deadline. We fit a three parameter model of GCs via: 1) arrival power of 3-9 from the number of hard steps in Earth history, 2) arrival constant from assuming inform distribution over the rank of today among GC origin dates, and 3) expansion speed > c/2 from our not seeing any GC volumes in our sky. We simulate this model to get distributions over outcomes, and how they vary with model parameters. Results: 40-50% of universe volume filled by GCs on average at GC origin dates.~200Myr – 2Gyr till we meet GC, if we become GC~10^5- 3*10^7 galaxies in each GC controlled volumeIf GCs arise from non-grabby civilizations (NGCs), a depressingly low transition chance (< ∼10^−4) seems required to expect even one other NGC ever active in our galaxy. Conclusions: Existing data are sufficient to motivate and estimate a model of loud aliens, saying where they are and when we will see or meet them. Life Beyond Earth: How will It First Be Detected? Life Beyond Earth: How will It First Be Detected? Author: Chris Impey Background: With the past decade of exoplanet discoveries, we now know there are tens of billions of habitable planets in our galaxy. The next stage in astrobiology research will be the first detection of life beyond Earth, a dramatic event in the history of science. Objective: By various approaches, the objective is unequivocal evidence of biology elsewhere. All indications are that the raw chemical materials for biology are widespread in the universe, and life needs only water, carbon-rich material, and a local energy source to begin and survive. Detection will require frontier observations, working at the limits of telescopes and remote sensing. Two extreme options are possible: that life is abundant and occurs anywhere with suitable conditions, or that there are one or more difficult or unlikely steps in evolving to a cell so life on Earth is unique or a fluke. Methods: The first detection of life beyond Earth could come from three distinct research paths. One is the exploration of habitable locations in the Solar System, particularly the surface (fossilized life) or sub-surface (extant life) of Mars, but also Europa, Enceladus and Titan. Life-detecting missions to these destinations are a decade or more away. The second is a search for biosignatures, spectroscopic indicators of the alteration of atmospheres of Earth-like exoplanets due to a microbial metabolism. Such observations will be enabled by upcoming huge ground-based telescopes like GMT and TMT, and by upcoming space telescopes like JWST. The third is a search for technosignatures, evidence of technological civilizations far from Earth. SETI is the traditional means for this search, looking for narrow-bandwidth radio signals or pulsed optical signals. Other strategies involve looking for alien artifacts or sentinels in the Solar System or detecting advanced life forms by their energy footprint or waste energy emission. Results: The feasibility and timeline of each of these approaches will be discussed, along with novel methods for life detection. Conclusions: The discovery lies in the future. The conclusion will be an educated guess to the date and means of detecting Life 2.0. The Interstellar Ramjet: Engineering Nightmare The Interstellar Ramjet: Engineering Nightmare Authors: Albert Jackson and Peter Schattschneider Ph. D Description: Long ago it was noted that the mass ratio problem is for an interstellar spacecraft was an enormous problem. One solution was to acquire propellant along the route, such a propulsion system to get around the mass ratio problem was formulated by Robert Bussard in 1960. His solution, the interstellar ramjet, which would gather interstellar hydrogen and through hydrogen fusion provide thrust. Bussard and later Dan Whitmire noted the extreme reactor conditions needed for the proton-proton reaction. Whitmire showed for the p-p process that the reactor length would have to be about 1000 km long! Bussard noted that to scoop hydrogen for a 1g ship one need an inlet area of the collector to be of the order of 1000 km in radius. Bussard also proposed that a magnetic field might be used as the collection agent. Recently we have shown that there are sever constraints on a magnetic ram scoop. Namely that the characteristic size and mass of the source of the magnetic field can be of the order of hundreds of kilometers and a thousand kilotons respectively. This is an extreme constraint on the engineering physics of an interstellar ramjet. Fishback’s limit on final mission speed is a much smaller value now. All this before one considers system efficiencies, radiation losses, drag and radiation damage. Further the scoop constraints limit the viability of the augmented and laser powered ramjets. Design of an Gravitational Lens Point Probe Utilizing Self-Guided Beamed Propulsion Design of an Gravitational Lens Point Probe Utilizing Self-Guided Beamed Propulsion Authors: Rohan Jillapalli, MEng, Trent Collins, BS, Chris Limbach, PhD, and Hayden Morgan, MS Background: A new beam propulsion concept utilizing overlapped laser and particle beams has been proposed with potential for long-range self-guiding and high momentum transfer efficiency. However, compatibility with the propulsion architecture requires a spacecraft that can survive the bombardment of neutral atoms and a high intensity laser. It is, therefore, necessary to develop methods for shielding the spacecraft while efficiently harnessing the momentum transfer. The work presented here describes the design of a spacecraft tailored for a solar gravitational lens mission which is propelled by the self-guided beam concept. Objective: The objective of this work is to evaluate a spacecraft design for a solar gravity lens mission in which the spacecraft is propelled by the concept beam propulsion method. Methods: A magnetic shielding approach is proposed whereby neutral particles are ionized through a two-step photo-ionization process consisting of excitation by an on-board laser and subsequent ionization by the overlapped self-guiding laser. The ionization of the particles produces a plasma beam which is shielded in similar fashion to the mini-magnetosphere concept. A superconducting coil configuration was designed to generate magnetic field strength sufficient to avoid direct impingement of the plasma beam on surfaces. To protect the craft from the co-propagating laser, high reflectivity mirrors and thermal management systems were designed. Results: For this mission, design tools were used to determine a science spacecraft mass budget of 100 kg and an on-board power budget of 250 W. The acceleration and final velocity of the craft are 21.4 m/s^2 and 200 km/s, respectively. Using calculated input values for incident mass and heat fluxes, thermal analysis revealed the spacecraft chassis temperature remained below 395 K. Utilizing the proposed ionization scheme along with the allocated power budget, the ionization model yielded over 90% ionization of the neutral beam. Conclusion: The proposed spacecraft design, which utilizes the self-guided particle and laser beam propulsion method, shows promise for withstanding the atomic beam and laser power influx during the acceleration phase of the mission. The lessons learned during the design process also provides value in informing future interstellar missions with a focus on critical areas for mass reduction which include the magnetic shielding and heat rejection subsystems. Flyby, deceleration, or orbit insertion? Critical mission design parameter Flyby, deceleration, or orbit insertion? Critical mission design parameter Author: Pauli Laine Description: It is a daunting engineering task to develop propulsion system for a meaningful interstellar mission. Interstellar vehicle must be accelerated to velocity that is significant part of the speed of light in order to reach light-year distances within foreseeable future. Other (and relatively rarely processed) daunting engineering task is how to slow vehicle down when target stellar system is reached, or how to carry out meaningful measurements and other mission objectives during the very short flyby time. However, choosing between deceleration, orbit insertion, and flyby is the key parameter for any interstellar mission. If slowdown requires propellant it will increase the initial mass of the vehicle, and will affect the overall design of the mission. On the other hand, could reasonable slowdown be done without propellant, e.g. with solar sail against stellar wind? Some proposed deceleration and flyby designs are presented here. Arts and Recreation on Mars: Contributing to Quality of Life in the Leominster Community Arts and Recreation on Mars: Contributing to Quality of Life in the Leominster Community Author: Bart Leahy Description: How can the arts and recreation contribute to quality of life in off-world civilization? It is the author’s belief that arts and recreation can become a regular, organized part of life off Earth once people reach the point of building large cities with the resources to support them. Given the importance of the arts and recreation throughout human history, we should also expect them to become an essential part of life as we migrate beyond Earth. Because the Moon is so close to Earth, I will focus on people migrating to Mars. The paper is written as a report to future city planners for Leominster, a fictional 1,000-person city being built on Mars. The report will explain the need to incorporate arts and recreational spaces into their community consciously and deliberately; how arts and recreation can be incorporated into the design of Leominster; and how they can serve as a draw for future residents. Additional world-building assumptions for Leominster will include its architecture, technological capabilities, and industries; the city’s history, economy, and designed living conditions; and the characteristics of the people choosing to live there. The inhabitants will have to cope with the extreme environment (frigid temperatures, thin/unbreathable atmosphere, high radiation, months- or years-long dust storms, etc.) as well as life within a built community (no access to fresh air, “outside” mediated by spacesuits or vehicles, confinement, life support emergencies, and physical and communication distance from Earth). Because of these challenges, the report will cite analogous peoples who experienced similar pressures, including migrant and displaced populations; confined and imprisoned people; nuclear submarine crews; early explorers and space analogue participants; and previous space crews. The report will identify how art and recreation helped these isolated people survive; recommend specific types of art and recreation for Leominster; and clarify how they will contribute to life in the new city. I intend to show how arts and recreation can contribute to life in a single Mars city but also how they can advance the course of human civilization beyond Earth. Quantitative Characterization of Photonic Sail Candidates using Nanocantilever Displacement Quantitative Characterization of Photonic Sail Candidates using Nanocantilever Displacement Author: Joseph E. Meany, Ph.D. Background: Demonstrations of photonically-propelled materials for solar and laser sailing have relied on indirect techniques for determining the propulsion efficiency. These methods, utilizing drop towers or cameras to determine differential displacement, are necessarily low-throughput and cannot be easily compared directly. Furthermore, the methods require sample sizes that are prohibitive to the fabrication of low TRL photonic materials (e.g. thin-film metasurfaces) that discourages rapid iterative testing. Herein, a nanocantilever-based test bed is proposed to simplify and standardize the determination of the characteristic acceleration for a given sail swatch. The proposed system is designed to allow for flexible, automated spectral analysis, requiring sample sizes ~10 µm2. This system is scalable to the micro- and macroscale as material technologies mature and advance toward deployment scale. Objective: Outline the physical principles underlying a nanocantilever detection system to support small-area swatches of candidate photonic sail materials. Methods: Classical physics modelling to support the basic feasibility of the approach. Current Ground Experiments for Self-Guided Laser and Atomic Beam Space Propulsion Current Ground Experiments for Self-Guided Laser and Atomic Beam Space Propulsion Author: Hayden Morgan Background: Beamed energy space propulsion concepts must contend with beam divergence during propagation through space, resulting in reduced thrust during the later period of acceleration. A combination of a spatially overlapped laser beam and atomic beam shows capability for self-guiding and significantly reduces the detrimental impact of divergence. The laser light is guided through the higher refractive index in the atomic beam. In a corresponding way, the atoms are guided via an optical dipole trap that draws particles toward the regions of high laser intensity. Objective: The research objective is to demonstrate and quantify a mutual self-guiding effect through the development of ground experiments that provide a reasonable space analogue environment. Methods: To characterize the propagation of the atomic beam, multiple laser diagnostic stations are installed along the propagation axis to extract the density and temperature cross-sections. Overlapped laser characterization is completed using a novel beam decoupler system that allows a camera to image the final state of the laser beam profile with and without the influence of the atomic beam. Results: Data from the recent overlapped experiment is still being processed, however, from cursory evaluations it appears that a low intensity laser beam tuned closer atomic resonance exhibited some fluctuations in a spatial intensity profile that could indicate a light guiding behavior of the atomic beam. Additionally, by tuning the spatially overlapped laser across the atomic resonance, an axial velocity distribution of the atoms can be obtained. This absorption behavior of the atomic jet was seen in the experiment as laser intensity at the end of propagation changed with the laser tuning across the atomic resonance. Further analysis will identify if the atomic density distribution changed with the laser tuning parameters, or if the dipole force was too weak and further cooling of the atoms is necessary. Conclusion: Demonstration of the self-guiding behavior and quantification of how it manifests for both constituents will provide key datasets for validation of computational models. These simulations can then be used to predict capabilities of proposed full-scale in-space infrastructure. This work will also identify areas for improvements with the design of the atomic beam, atomic cooling methods, and diagnostic capabilities. Wormholes, Warp Drives, and Other Possible Means of Interstellar Migration Wormholes, Warp Drives, and Other Possible Means of Interstellar Migration Author: Gonzalo Munévar Background: Interstellar migration may allow humanity, as well as a good number of other terrestrial lifeforms, to survive for billions of years after the Sun’s increasing energy output destroys all life on Earth. Interstellar distances, however, make trips to other star systems tens of thousands of years long, given our present technology for space travel. It is not surprising, then, that the topic of faster-than-light travel, or at least the achieving of high relativistic speeds, should acquire great importance. Objective: A full survey of the alternative proposals is beyond the scope of this talk, but I will briefly discuss Wheeler wormholes and Alcubierre’s Warp Drive, before making a case for why a Gerard O’Neill type of Space Colony propelled at high relativistic speeds would be the most promising means to carry out successful interstellar migration. Methods: Analysis of the scant evidence for Wheeler’s spacetime foam or wormholes. The appeal to the Casimir Effect is based on a misunderstanding. The time-travel paradoxes are a final blow. Alcubierre’s Warp Drive is consistent with General Relativity, but its engine needs exotic matter. Analysis of Space Colony propelled by a Whitmire ramjet to high relativistic speeds: A Space Colony would be home to at least tens of thousands of scientific experts who can use the resources of another star system to transform it. The ramjet finds its fuel in the hydrogen from space. The heat from its reactor is a solvable problem. The ramjet is also preferable to laser propulsion and its small payloads. Results: Successful migration requires a large human contingent to prepare the new star system, particularly terraforming one or more planets, which may take decades if not centuries. Placing a large space colony offers the best chances of success. After settling those planets, it can move to another star, or a new traveling colony can be built for that purpose. Conclusions: A Whitmire-ramjet-propelled Space Colony offers the most plausible means to initiate interstellar migration within two centuries or so. Quantum Gravity as a Quantum Warp Field Quantum Gravity as a Quantum Warp Field Author: Glen A. Robertson, BS in Mathematics, BS is Physics, MS in Operation Research Background: The combined quantum mechanical and energy fluctuations in objects and the quantum energy fluctuations in the external quantum energy field surrounding objects are two separate quantum energy fields separated by a thin energy shell of quantum fluctuations (ESQFs), emanating from the surface of objects. The ESQFs about objects is entangled to the internal and external quantum energy fields to mediate differences that occur between the two quantum energy fields. Whereby, when a small object approaches a larger object, the external quantum energy field of the large object creates an asymmetric change in the external quantum energy field about the smaller object; resulting in an asymmetric change in the ESQFs mediation about the smaller object. This asymmetric change in the ESQFs mediation results in gravitational acceleration on the small object, to produce a quantum gravity model that looks like a warp field. Further, this asymmetric ESQFs mediation can be extended to all other forms of acceleration to include warp drive models. This comes about by analyzing the quantum energy fluctuations about objects as a Casimir cavity, and connecting it to the thin-shell mechanism in Chameleon Cosmology (CC), which suggest that the thin-shell in CC is an ESQFs. Whereby, the formulation of the thin-shell thickness in CC is the wavelength of the quantum energy fluctuations in the ESQFs about objects. It is then shown that the entangled coupling across an object asymmetrically changes as objects approach one another to asymmetrically change the ESQFs thickness about the objects. With the change less noticeable on the largest object (gravitational mass). Whereby this asymmetric change in the ESQFs thickness is shown to resemble a warp field. Further, it is proposed that this asymmetric change in the ESQFs thickness occurs during the acceleration of objects at any speed – to include warp speed. Objective: To show that there is a quantum gravity analogy to acceleration to allow future development of space propulsion methods without mass ejection. Method: The Quantum Gravity as a Warp Field model leads to the concept of asymmetric changes in the ESQFs about accelerated objects. Results: The asymmetric changes in the ESQFs about accelerated objects are like warp bubbles, producing acceleration similar to warp bubbles theory. Conclusions: The Quantum Gravity as a Warp Field model shows that new space propulsion methods without mass ejection – to any speed – are possible through engineering methods that can produce asymmetric changes in the ESQFs about spacecrafts. SIMOC: An agent-based model of hybrid physico-chemical and bioregenerative life support and food production for long-duration missions and other-world habitation. SIMOC: An agent-based model of hybrid physico-chemical and bioregenerative life support and food production for long-duration missions and other-world habitation. Authors: Kai Staats and Ezio Melotti A Scalable, Interactive Model of an Off-World Community (SIMOC) is an agent-based model and web interface to a human habitat simulator built on NASA human factors and plant physiology data. Funded by Arizona State University, University of Arizona, and National Geographic, a SIMOC users design a habitat by selecting various combinations of mechanical (physico-chemical) and plant (bioregenerative) systems, greenhouse and food cultivars, energy generation and storage; astronauts, rations, and mission duration. The dashboard provides numerical and graphical display of various atmosphere components, water, and power levels; food cultivar growth, harvest, and consumption; and the overall health of the human inhabitants. All data can be downloaded and analyzed, and simulations stored and shared by other users. In its current offering, SIMOC simulates hour-by-hour, up to two years of a closed ecosystem. At the core of this Python engine is an agent-based model whose functions are not bound to any planetary location or time frame. With relatively minor adjustments to the agent definitions file, SIMOC could be made to simulate much longer duration missions, extending to multi-generational interstellar voyages. Objective – To discover the minimum complexity required by a hybrid physico-chemical/bioregenerative life support system for long-duration missions and other-world habitation. Methods – Development of a research-grade, agent-based model built upon four decades human factors and plant physiology data at NASA, Universities, and Paragon SDC. Results – The results depend on the input parameters of the given habitat design and subsequent simulation. Conclusions – Users learn the challenge in finding a balance between rations and harvested food, mechanical and bioregenerative air recycling, power generation, storage, and consumption. Relatively simple, linear functions form non-linear interactions that over time make long-duration mission design quite challenging. Detectability of Artificial Lights from Proxima b Detectability of Artificial Lights from Proxima b Screenshot Author: Elisa Tabor Description: We investigate the possibility of detecting artificial lights from Proxima b’s dark side by computing light curves from the planet and its host star. The two different scenarios we consider are artificial illumination with the same spectrum as commonly used LEDs on Earth, and a narrower laser spectrum which leads to the same proportion of light as the total artificial illumination on Earth. We find that the James Webb Space Telescope (JWST) will be able to detect LED type artificial lights making up 5% of stellar power with 85% confidence, assuming photon-limited precision. In order for JWST to detect the current level of artificial illumination on Earth, the spectral band must be 10^3 times narrower. Our predictions require optimal performance from the NIRSpec instrument, and even if not possible with JWST, future observatories like LUVOIR might be able to detect this artificial illumination. Relativistic Braking and Power Generation through Stellar Magnetic Fields via Eddy Current Forces Relativistic Braking and Power Generation through Stellar Magnetic Fields via Eddy Current Forces Author: Colin Warn Description: A method of braking a spacecraft moving at relativistic speeds by means of circulating Eddy Current forces in a metal is proposed. An example calculation using a sail made from the wonder-material graphene, it is hypothesized that an approximately 500 m2, 1g sail can be decelerated completely from 8% the speed of light in 127 seconds through a magnetic field that is roughly as long as the diameter of a star, while generating around 26 W of power. This method, if experimentally shown to be feasible, can be improved by increasing the melting point of the spacecraft materials, as well as the maximum deceleration rating of spacecraft electronics and payloads. Power from Below the Ice: Geothermal Energy Generation on Icy Moons Power from Below the Ice: Geothermal Energy Generation on Icy Moons Author: Ken Wisian Description: As humanity explores and expands into the outer solar system, practical sources of power will be needed for permanent instillations and colonies. For robotic exploration to date this has meant solar panels or radioactive fission sources. Each of these power sources have significant drawbacks; solar is subject to the inverse square law of decreasing solar irradiance, while fission sources emit radiation that must be protected against with shielding mass and distance. One possibility that has potential for powering instillations on many outer solar system bodies is geothermal generation. This technology has been producing electricity on Earth for more than 100 years and direct use heat for thousands of years. Conventional geothermal systems are a mature technology and one of the cleanest energy sources today. A new paradigm of zero emission, deep closed-loop geothermal systems is in early trails now. Which type of geothermal power system is best applied will depend on the specific geologic setting, economic, environmental and other policy considerations. Fundamentally all that is needed to produce energy in a geothermal sense is an exploitable temperature differential. On many icy bodies this differential would come from the difference between the surface temperature and a subsurface liquid body. Most commercial geothermal power plants work of the difference between ambient surface air temperature (~25°C) and a subsurface fluid temperature of 200 ± 50°C. This examination mostly focuses on the potential of shallow sub-ice oceans that are approximately 175-200°C warmer than the surface of the body at approximately -200°C. For this setting, what is needed is a -200°C shift in the entire temperature cycle of Earth-bound geothermal systems. While there are significant engineering issues to be solved in producing this energy, the potential, particularly on icy bodies is on the order of Megawatts of power generation per well with no imported fuels (radioisotopes) needed.