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General Interstellar Issue Journal of the British Interplanetary Society VOLUME 72 NO.6 JUNE 2019 General interstellar issue THE MOTIVATION AND FREQUENCY OF INTERSTELLAR MIGRATIONS: A Possible Answer to Fermi’s Paradox Gregory L. Matloff TOWARDS A COMPREHENSIVE BIBLIOGRAPHY FOR SETI: Alan Reyes & Jason Wright ULTRAHIGH ACCELERATION NEUTRAL PARTICLE BEAM-DRIVEN SAILS James Benford & Alan Mole THE IMPLICATIONS OF NON-FASTER-THAN-LIGHT TYPE-3 KARDASHEV CIVILIZATIONS Agustín Besteiro HUMANITY’S FIRST EXPLICIT STEP IN REACHING ANOTHER STAR: The Interstellar Probe Mission Pontus Brandt et al. www.bis-space.com ISSN 0007-084X PUBLICATION DATE: 29 AUGUST 2019 Submitting papers International Advisory Board to JBIS JBIS welcomes the submission of technical Rachel Armstrong, Newcastle University, UK papers for publication dealing with technical Peter Bainum, Howard University, USA reviews, research, technology and engineering in astronautics and related fields. Stephen Baxter, Science & Science Fiction Writer, UK James Benford, Microwave Sciences, California, USA Text should be: James Biggs, The University of Strathclyde, UK ■ As concise as the content allows – typically 5,000 to 6,000 words. Shorter papers (Technical Notes) Anu Bowman, Foundation for Enterprise Development, California, USA will also be considered; longer papers will only Gerald Cleaver, Baylor University, USA be considered in exceptional circumstances – for Charles Cockell, University of Edinburgh, UK example, in the case of a major subject review. Ian A. Crawford, Birkbeck College London, UK ■ Source references should be inserted in the text in square brackets – [1] – and then listed at the Adam Crowl, Icarus Interstellar, Australia end of the paper. Eric W. Davis, Institute for Advanced Studies at Austin, USA ■ Illustration references should be cited in Kathryn Denning, York University, Toronto, Canada numerical order in the text; those not cited in the Martyn Fogg, Probability Research Group, UK text risk omission. Raghavan Gopalaswami, Aerospace Researcher, India ■ Captions must be labelled with their Fig. number and should be as short as possible. Lamartine Guimarães, Institute for Advanced Studies, Brazil Mark Hempsell, Hempsell Astronautics Ltd, UK Illustrations should be: Takuto Ishimatsu, Massachusetts Institute of Technology, USA ■ Colour or mono, but should be as close to print Les Johnson, Marshall Space Flight Center, USA resolution (300 dpi) as possible. Poor-quality illustrations may compromise the acceptance of Terry Kammash, University of Michigan, USA paper for publication. Images embedded in Word Kelvin F. Long, Initiative for Interstellar Studies documents may be acceptable, but JBIS reserves Inoue Makoto, Institute of Astronomy & Astrophysics Academia Sinica, Taiwan the right to request separate higher-resolution Gregory L. Matloff, City University New York, USA image files from the author prior to publication. Koichi Mori, Nagoya University, Japan ■ Responsibility for copyright clearance of images rests entirely with the author. Richard Obousy, Richard Obousy Consulting LLC, USA Robert Parkinson, BIS, Aylesbury, UK Submission of papers George Schmidt, NASA John H Glenn Research Center, Ohio, USA ■ Papers for consideration should be sent by Paul Schuch, The SETI League Inc, USA email to [email protected] as both a Word document and as a Word PDF file (in order to Tabitha Smith, Bifrost, USA check for font anomalies), together with any Andreas Tziolas, Variance Dynamical Corporation, USA separate image files. Chris Welch, The International Space University, Strasbourg, France ■ If a paper is accepted for publication, the Friedwardt Winterberg, University of Nevada, Reno, USA author will be asked to sign a License to Publish form. This can be downloaded at www.bis- space.com/wp-content/uploads/2012/08/ WebsiteLicense.pdf. ■ Authors will receive a complimentary copy of the issue in which their paper appears. Editor Roger Longstaff Deputy Editor Duncan Law-Green Associate Editors Stephen Ashworth, We respectfully ask authors to adhere to these Keith Cooper, Stephen Gamble, Paul Gilster, Rob Swinney, Production MP3 Media guidelines. Failure to do so will result in the Promotion Gill Norman JBIS Office British Interplanetary Society, Arthur C. Clarke House, delay of acceptable papers for publication. 27-29 South Lambeth Road, London, SW8 1SZ, United Kingdom tel +44 (0)20 7735 3160 email [email protected] www.bis-space.com Our full Guidelines for Authors can be downloaded DISTRIBUTION from www.bis-space.com JBIS is distributed worldwide by mail and may be received by annual subscription or purchase of single copies. It is available through membership of the British Interplanetary Society at much reduced rates. Subscription details for members, non-members and libraries are available from the above address. JBIS is a publication that promotes the mission of the British Interplanetary Society. Opinions expressed in signed articles are those of the contributors and do not necessarily reflect the views of the Editor or the Council of the British Interplanetary Society. Security clearance, where necessary, is the responsibility of the author. Published by the British Interplanetary Society. Registered Company No: 402498. Registered Charity No: 250556. Printed by Latimer Trend & Company Ltd, Estover Road, Plymouth, PL6 7PY, England. © 2019 British Interplanetary Society. No part of this magazine may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying or recording by any information storage or retrieval system without prior permission from the Publishers. CONTENTS VOLUME 72 NO.6 JUNE 2019 182 THE MOTIVATION AND FREQUENCY OF INTERSTELLAR MIGRATIONS: A Possible Answer to Fermi’s Paradox Gregory L. Matloff 186 TOWARDS A COMPREHENSIVE BIBLIOGRAPHY FOR SETI Alan Reyes & Jason Wright 190 ULTRAHIGH ACCELERATION NEUTRAL PARTICLE BEAM-DRIVEN SAILS James Benford & Alan Mole 198 THE IMPLICATIONS OF NON-FASTER-THAN-LIGHT TYPE-3 KARDASHEV CIVILIZATIONS Agustín Besteiro 202 HUMANITY’S FIRST EXPLICIT STEP IN REACHING ANOTHER STAR: The Interstellar Probe Mission Pontus Brandt et al. OUR MISSION STATEMENT The British Interplanetary Society promotes the exploration and use of space for the benefit of humanity, connecting people to create, educate and inspire, and advance knowledge in all aspects of astronautics. JBIS Vol 72 No.6 June 2019 181 JBIS VOLUME 72 2019 PAGES 181–185 THE MOTIVATION AND FREQUENCY OF INTERSTELLAR MIGRATIONS: a Possible Answer to Fermi’s Paradox GREGORY L. MATLOFF Physics Dept., New York City College of Technology, CUNY, 300 Jay St., Brooklyn, NY 11211, USA Email [email protected] Human space exploration and exoplanet discoveries raise Fermi’s Paradox (“Where is Everybody?”) to new heights. The author suggests that technologically advanced interstellar civilizations might defer interstellar migration until their host stars enter the post-main-sequence ~108-year subgiant phase. Increased stellar luminosity will then enhance the performance of solar-photon-sail spacecraft. A scenario is presented for a 109-kg generation ship propelled by a graphene sail. The best destination for such a migration is a widely separated giant-dwarf binary. The giant would be used for deceleration; the vicinity of the dwarf would be colonized. At least one such system would likely closely approach the host star during its subgiant phase. Keywords: Fermi’s Paradox, Solar Sails, Stellar Evolution, Binary Stars, Interstellar Migrations 1 INTRODUCTION: WHERE IS EVERYBODY? [6]. Current radio-astronomy searches have been funded in an effort to resolve this paradox [7]. The Space Age is only seven decades old. In this short time, humans have lived in space for over one year, visited our Moon, Starting in the 1990’s, advanced observational techniques dispatched robotic probes to all major planets in our solar sys- have demonstrated the existence of thousands of planets with- tem and many smaller celestial objects and launched gravi- in the Milky Way Galaxy. Very recently, it has been shown that ty-assisted probes on slow voyages into our galaxy. Although Proxima Centauri, the nearest star to our Sun, is likely attended chemical rockets have propelled most of these ventures, some by a small planet orbiting in this red dwarf’s habitable zone [8]. craft have been propelled by solar-electric propulsion. Three Potentially habitable planets seem common in our galaxy. spacecraft to date have successfully tested the principle of pure photon propulsion by unfurling solar-photon sails. If current scientific speculation regarding the origin of life approximates reality, many of these planets support or have Experiments with beamed propulsion have been performed supported active biospheres. Intelligence may have evolved on and the construction and launch of wafer-thin interstellar some of these distant worlds. Some extraterrestrial societies probes propelled by the pressure of photons in microwave or may be technological. laser beams does not seem to be an unreasonable goal for the not-too distant future [1]. Yes, based upon humanity’s own sorry history, many devel- oping extraterrestrial civilizations might self-destruct through Self-sufficient space habitats constructed using lunar or as- nuclear war, pandemics, climate change, over-population, po- teroid material have been studied in depth [2,3]. It seems that litical turmoil, etc. But certainly, some among the millions or deep-space craft supporting hundreds or thousands of humans billions of habitable
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