Principium is the community magazine of the Initiative for Interstellar Studies and the Institute for Interstellar Studies (USA). It features educational articles, accessible technical articles and news from the interstellar community and the wider world of space exploration. It presents an inspiring vision of the future humankind - if we work hard to achieve it.
Principium is a quarterly free publication of the Initiative for Interstellar Studies. You can download copies of all issues below. Here's the latest! Members of i4is can access select articles from upcoming issues of Principium before they are made publicly available.
We hope you enjoy reading our magazine.
John I Davies & Patrick J Mahon, Editors, Principium
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Principium Issues
Issue 46 | August 2024
P46 is here!
https://i4is.org/wp-content/uploads/2024/08/Principium46-2408260749comp.pdf
LEAD FEATURE
An Improbable Pursuit: Introduction to the Current Thinking on Faster-Than-Light (FTL) Travel
FEATURES
Launching politics into outer space – A review of The Terrestrial Trap: International Relations beyond Earth
The Cosmic Challenge: Why Quantum Entanglement Won’t Deliver The Ansible
Long Life and the Longest Journey: Musings on life extension for world ship missions
NEWS FEATURES
International Astronautical Congress IAC24: The Interstellar Presentations
Project Lyra Update: Starships and Swarms
Breakthrough Discuss 2024: What was discussed and what was not
The Journals
REGULARS
Become an i4is member
Cover Images
Comments on i4is and all matters interstellar are always welcome. Write to us –
John I Davies, Editor, Principium
john.davies@i4is.org
Patrick J Mahon, Deputy Editor, Principium
patrick.mahon@i4is.org
Keep in touch!
Back issues of Principium, from number one, can be found
at www.i4is.org/Publications/Principium.
Issue 45 | May 2024
Principium 45
https://i4is.org/wp-content/uploads/2024/05/Principium45-2405171117-comp.pdf
Contents – click link to access each article individually-
LEAD FEATURE: book review, Les Johnson’s A Traveler’s Guide to the Stars.
Book Review: Contact with Extraterrestrial Intelligence and Human Law
NEWS FEATURES:
Glasgow 24 SF Worldcon An i4is update
https://i4is.org/wp-content/uploads/2024/05/Glasgow-24-SF-Worldcon-Principium45-2405171117-comp.pdf
Royal Institution April 2024 – Our fifth Skateboards to Starships workshop
Biological intelligence vs AI – and the Fermi Paradox
The Journals
https://i4is.org/wp-content/uploads/2024/05/The-Journals-Principium45-2405171117-comp.pdf
– and 12 pages of INTERSTELLAR NEWS
https://i4is.org/wp-content/uploads/2024/05/interstellar-news-Principium45-2405171117-comp.pdf
Next Issue
https://i4is.org/wp-content/uploads/2024/05/next-issue-Principium45-2405171117-comp.pdf
Members Page
https://i4is.org/wp-content/uploads/2024/05/the-i4is-members-page-Principium45-2405171117-comp.pdf
Become an i4is member
https://i4is.org/wp-content/uploads/2024/05/become-an-i4is-member-Principium45-2405171117-comp.pdf
Issue 44 | February 2024
LEAD FEATURE Hazards of Interstellar Propulsion
NEWS FEATURES The First European Interstellar Symposium, IRG 23: ‘Metropolis’ Revisited… and Coming, NASA NIAC funds swarming study, The 2024 World Science Fiction Convention – Glasgow, IRG23: The Ultimate Rocket the Ultimate Energy Source and their Use in the Ultimate Future, Define Artificial General Intelligence!, SETI Institute announces Breakthrough Listen funding, IAC 2023: The Interstellar Presentations. Part 2, The Journals
– and 5 pages of –
INTERSTELLAR NEWS Principium will have a News Editor, Sail Trajectories to Proxima b, We’re all doomed!, On the first probe between two interstellar civilisations, Photovoltaic Onboard Power for Interstellar, Selection of News from our Members’ Newsletter, Plenty of room at the bottom, Matter/Anti-Matter Propulsion
REGULARS: Become an i4is member, the i4is members’ page, Next Issue, Cover Images
Issue 43 | November 2023
The November 2023 issue of Principium is now available and has already gone out to subscribers.
LEAD FEATURE
IRG23: The Summaries
FEATURE
Natural Geo-engineering of the early Earth
NEWS FEATURES – IRG 23
X-ray and γ-ray Beam Interstellar Communication and Implications for SETI, Applications and Design Guidelines for High Power Lasers in Space Exploration, Silence is Golden: SETI and the Fermi Paradox, Infrastructure Development Leading to the First Long-Duration Interstellar Probe, The Linguistics of Arrival: Universal Grammar and Interstellar Communication, The Promise of Beamed Energy for Spacecraft Propulsion, Constraints on Interstellar Sovereignty – a summary, Vanquishing Dark Skies The role of national space forces in security, safety, and prosperity through space exploration
OTHER NEWS FEATURES
i4is at the Royal Institution 2023 – our fourth year, IAC 2023: The Interstellar Presentations. Part 1, BIS Symposium brings Project Icarus to a close, Interstellar Studies – Inspiring the next generation, The Journals
- and 17 pages of INTERSTELLAR NEWS
Issue 42 | August 2023
LEAD FEATURES
Two IRG23 REPORTS – https://i4is.org/wp-content/uploads/2023/08/IRG23-reports-Principium42-2308271041opt.pdf
IRG23 – The First Two Days
On Lasers and Lagrange Points- 8th Interstellar Symposium
NEWS FEATURES
Interstellar flyby scientific data downlink design – https://i4is.org/wp-content/uploads/2023/08/Interstellar-flyby-scientific-data-downlink-design-Principium42-2308271041opt.pdf
Project Icarus revisited – 30 September – https://i4is.org/wp-content/uploads/2023/08/News-Feature-Project-Icarus-revisited-30-September-Principium42-2308271041opt.pdf
IAC 2023 – The Interstellar Presentations – https://i4is.org/wp-content/uploads/2023/08/IAC-2023-The-Interstellar-Presentations-Principium42-2308271041opt.pdf
The Journals – https://i4is.org/wp-content/uploads/2023/08/The-Journals-Principium42-2308271041opt.pdf
INTERSTELLAR NEWS – https://i4is.org/wp-content/uploads/2023/08/interstellar-news-Principium42-2308281223opt.pdf
REGULARS
Become an i4is member The i4is members’ page Membership poster-black Membership poster-white Next issue Cover images
Issue 41 | May 2023
FEATURES
BOOK REVIEW: Astrotopia: Dangerous Religion of the Corporate Space Race
Project Lyra: What SpaceX could do
NEWS FEATURES
IRG23 Preview
Rob Swinney at the Royal Aeronautical Society
i4is delivers Communications Study to Breakthrough Starshot
Cost-Optimal System Performance Maps for Laser-Accelerated Sailcraft
The Journals
12 pages of Interstellar News
REGULARS:
Become an i4is member
The i4is members’ page
Next issue
Issue 40 | February 2023
FEATURES
Searching for Alien Messages to a Nearby Star
The Mariner 2 Model
NEWS FEATURES
IAC 2022: The Interstellar Presentations. Part 2
i4is 10th Anniversary
The Journals
14 pages of Interstellar News
REGULARS:
Become an i4is member
The i4is members’ page
Next issue
Issue 39 | November 2022
Principium 39 – ISSN 2397-9127 –
FEATURES
BOOK REVIEW: FREEDOM IN OUTER SPACE
‘Oumuamua: A Second Chance? A Personal Memoir
I4IS Science Fiction Anthology
NEWS FEATURES
The Third i4is Summer School at the Royal Institution
i4is 10th anniversary
News Feature: IAC 2022: The Interstellar Presentations. Part 1
Impressions of IAC22
The Journals
16 pages of Interstellar News
REGULARS:
Volunteer Poster: Working towards the real Final Frontier
Become an i4is member
The i4is members’ page
Next issue
Issue 38 | August 2022
Principium 38- ISSN2397-9127
LEAD FEATURE Book Review: LIFE IN THE COSMOS, Andreas Hein
FEATURES: Two Equations to the Stars– Part Two: The Photon Sail Equation–John I Davies
NEWS FEATURES: IAC2022, The Journals
19 pages of INTERSTELLAR NEWS
REGULARS: Become an i4is member, The i4ismembers’ page, Membership and Volunteer posters, Next issue & Cover images
Issue 37 | May 2022
LEAD FEATURE Book Review: The Alien Communication Handbook, Patrick Mahon
FEATURES: Two Equations to the Stars – Part One – John I Davies, Finding new ways to share resources in space – Max Daniels
NEWS FEATURES: The Second Interstellar Studies Summer Course, IAC 2022, Special on space debris at IAC21 – Samar AbdelFattah, The Journals
INTERSTELLAR NEWS: IAC 2022, Inflatable infrared telescope to detect water, Engineering the Oberth Manoeuvre, A Starshade to help earth-based telescopes find exoplanets, i4is in US National Academies Decadal Survey, Don’t Forget To Look Up, Philosophy and Science of Space Exploration, Avoiding the Great Filter, Researching ‘Oumuamua as an Alien Craft, More from Centauri Dreams on Laser Sails and Ramping Up the Technosignature Search, Riding a laser to Mars in 45 days, The case for space environmentalism, Studying an ISO using the Webb telescope, SETI in 2021, Non-terrestrial artefacts in the Solar System, Probability of communicating ETIs
REGULARS: Membership Poster (white), Become an i4is member, Volunteer Poster: Working towards the real Final Frontier, The i4is members’ page, Next issue & Cover images
Issue 36 | February 2022
LEAD FEATURE The Icarus Firefly Downlink
FEATURES: Project Lyra: A Mission to 1I/’Oumuamua without Solar Oberth Manoeuvre, Design of Interplanetary Missions to Jupiter Using Optimum Interplanetary Trajectory Software
NEWS FEATURES: JBIS Index 2021, 72nd International Astronautical Congress 2021: The Interstellar Papers, A brief on IAC2021: Inspire, Innovate and Discover For the Benefit of Humankind, 7th Interstellar Symposium – The Hallway is More Important than the Podium…, The Journals
INTERSTELLAR NEWS: A real, albeit humble, warp bubble (continued)? ; Announcement from IRG, – See what we heard at Tucson; Free-floating planets in the Upper Scorpius, Capture of interstellar objects; Solid core thermal antimatter propulsion;, Feasibility of space solar power, Hyper-Fast Positive Energy Warp Drives; IEEE reports – A Pinch of Fusion, 100 GW beamer by coherent combination of 100 M lasers, JWST – so far so good; Interstellar communication from hypothetical alien, probes, UCSB on Economics of Interstellar Flight; Beyond Solar System – beware, Dark Matter, Trappist 1 – Gravitational Lens in 8 Years, Tailpiece: Wacky Scientists hire, wacky vicars – or not?
REGULARS: Keep An Eye On Our Facebook Page, Membership Poster (white), Become an i4is member, Volunteer Poster: Working towards the real Final Frontier, The i4is members’ page, Membership Poster (black), Next issue, Cover images.
Issue 35 | November 2021
- Interstellar Research Group Symposium 2021
- International Astronautical Congress 2021: The Interstellar Papers
- The downlink from swarming micro-probes
- News Features
- Nine pages of Interstellar News
- i4is Members’ Page
- Losing Access to Space – Are we building a fence around our planet? – A personal view
Issue 34 | August 2021
Issue 33 | May 2021
This issue features –
- LEAD FEATURE: Practicalities and Difficulties of a Mission to ‘Oumuamua
- The Self Replicating Factory: a work in progress
- The i4is Members Page
- Project Pinpoint: Pushing the Limits of Miniaturization
- Become an i4is member
- News Features:
- Interstellar News
- Book Review: Simone Caroti – The Generation Starship In Science Fiction
- Book Review: Avi Loeb – Extraterrestrial: The First Sign of Intelligent Life Beyond Earth
Issue 32 | February 2021
This issue features –
- AMiTe Treffpunkt — A proposal for communication between Kardashev Type IIb civilisations
- The Artemis Accords: what comes after the Moon?
- Worldship and self replicating systems
- An Interstellar Visitor: sorting the fact from the speculation
- 71st International Astronautical Congress 2020: The Interstellar Report — Part 2 of 2
- News Feature: Starshot Downlink Webinar
- The i4is Members Page & Become an i4is member
- Interstellar News
Issue 31 | November 2020
This issue features –
- Interstellar Objects & Sample Returns
- International Astronautical Congress 2020
- The Interstellar Downlink
- Book Review: Extraterrestrial Languages — Daniel Oberhaus
- News Features:
- Interstellar News
- i4is Members Page
Issue 30 | August 2020
This issue features –
- Worldship Implications of the BIS SPACE Project
- 2020 ISU MSS Elective Module
- i4is-supported ISU MSS Projects – Bussard Ramjet & Deceleration of Interstellar Probes
- 71st IAC 2020 Timetable of Interstellar Papers
- Cassidy Cobbs – Bioscientist – Part 2
- Interstellar News
- The Cathedral and the Starship
- FISW2 videos and presentations
- Educating i4is: the i4is Education Team
- Alfred M Worden – A personal reflection
Issue 29 | May 2020
This issue features –
- Cassidy Cobbs – Bioscientist
- Interstellar News
- The Interstellar Ram Jet at 60
- IAC2019 the Interstellar Papers #3
- FAST radio telescope & Breakthrough Listen
- Rings round exoplanets – possible megastructures
- Mariner model part 2: The initial construction phase
- i4is Members Page
- Freeman Dyson (1923-2020)
- Feasibility of self-replicating probes for interstellar exploration
- Book Review: Religions and Extraterrestrial Life
Issue 28 | February 2020
This issue features –
- IAC 2019 – Second Report
- Book Review: The Contact Paradox
- TVIW’s 6th Interstellar Symposium
- What do we really know about the Outer Solar System?
- The Equation used in the Benkoski Paper – A Derivation
- Interstellar Objects – Oumuamua, Borisov & objects in between
- i4is Members Page & Become an i4is member
- Interstellar News
Issue 27 | November 2019
This issue features –
- On a possible future direction for optical SETI
- IAC Oct 2019 — First Report
- How to reach Interstellar Visitors — Optimum Interplanetary Trajectory Software
- How low can you go? — The Benkowski equation
- i4is Members Page & Become an i4is member
- Interstellar News
Issue 26 | August 2019
This issue features –
- Foundations of Interstellar Studies Workshop 2019
- The State of the Art in Fusion Propulsion – part 2
- A Mariner 2 model
- Interstellar News
- News Features:
- The Principium Team
- Starship Congress 2019
- ESA Interstellar Workshop
- Apollo Poetry Competition result
- IAC Oct 2019 – i4is team and interstellar timetable
- ISU ChipSat Spacecraft and Mission Design elective
- i4is Members Page & Become an i4is member
Issue 25 | May 2019
This issue, Our third MEMBERSHIP Edition, features –
- The State of the Art in Fusion Propulsion
- Overview: TVIW 2018 Symposium
- Second Foundations of Interstellar Studies workshop
- Extreme Deep Space Exploration
- Competition: From Apollo to the stars!
- Progress & activity by i4is-US 2017-2019
- Fine Tuning Lasers: Project Dragonfly and Glowworm
- i4is Members Page and Become an i4is member
- Interstellar News
- News Features:
- Oumuamua, Project Lyra and ISOs
- Indian Anti-Satellite test
- All Comets Great and Small
- IAC 2018 – Swarm Systems
- i4is-US at annual MIT Beyond the Cradle event
- The Membership Team
Issue 24 | February 2019
This issue, Our second MEMBERSHIP Edition, features –
- Project Glowworm: Testing Laser Sail Propulsion in Low Earth Orbit
- Amerigo: Brief Overview of a 1000 AU probe study
- TVIW Power of Synergy Symposium
- Project Daedalus – A Beginners’ Guide
- Interstellar News
- News Features –
- Oumuamua, Project Lyra and Interstellar Objects
- 69th International Astronautical Congress 2018
- TVIW 2018
Issue 23 | November 2018
This issue, The MEMBERSHIP Edition, features –
- Implications of the Gaia Mission for Future Interstellar Travel
- News Feature – What is Oumuamua?
- Book Review: The Planet Factory – Elizabeth Tasker
- Engineering New Worlds: Goals, Motives and Results
- Interstellar News
- News Features:
- 69th International Astronautical Congress 2018 – The Interstellar Papers
- Starship Engineering – First Five Day i4is Summer School
- Holographic Photon Sails – A Merger of Science and Art
- The Andromeda Probe Model
- TVIW 2018
Issue 22 | August 2018
This issue features –
- To the Stars in a Century: Z-Pinch fusion & Firefly Icarus
- IAC 2018 Bremen – interstellar & i4is
- Breakthrough Propulsion Physics
- Book Review: Exoplanètes
- Interstellar News
- News Features
- Moon, Mars & beyond – an RI debate
- Catching A Little Bit of Heaven
- i4is HQ Symposium & Lecture
- Wormholes & Time Machines
- How far have we come?
Issue 21 | May 2018
This issue features –
- “Slow down!”: How to park an interstellar rocket
- The Orbits of Seveneves (2) – the orbits explained
- Imagining Interstellar – Art by Efflam Mercier
- 69th International Astronautical Congress 2018 – Papers by the i4is Team
- BOOK REVIEWS:
- Going Interstellar – Build Starships Now!
- Rendezvous with Rama, a retrospective
- NEWS FEATURES –
- Breakthrough Discuss 2018: i4is debate novel propulsion technologies
- PROCSIMA – Diffractionless Beamed Propulsion for Breakthrough Interstellar Missions
- BIS report on nanosats from the UK
- Interstellar News & Project Lyra Update
Issue 20 | February 2018
This issue features –
- Project Lyra : mission to ʻOumuamua
- Preparing for the next Interstellar Object
- Interstellar News
- The Orbits of Seveneves
- Tsiolkovsky – Interstellar Pioneer
- NEWS FEATURES
- Work on the interstellar asteroid and i4is Project Lyra
- Pete Worden, Breakthrough Initiatives, at i4is HQ
- Sir Arthur C Clarke Centenary
- Models and art at the Mill
Issue 19 | November 2017
This issue features –
- ‘The Interstellar Space’ Opening of i4is HQ, 8 October 2017
- News Feature – Glowworm Update
- TV Programme Review – The Search for a New Earth – With Professor Stephen Hawking, BBC2, first screened 11 Sep 2017, UK
- Interstellar Inspiration for School Students: The i4is Interstellar Challenge. How To to get started on your own Interstellar Challenge.
- Transplutonium is not “Planet X” : Reminiscing and reality-based ruminations on the high cost of nucleosynthesis of propellants for interstellar travel.
- Engineering New Worlds: Creating the Future – Parts 4 and 5
- Art for Interstellar : Bringing art, technology and science together in New York
Issue 18 | August 2017
This issue features –
- Aridopolis : A Sustainable Earth / Mars Desert Settlement
- Interstellar News
- Engineering New Worlds: Creating the Future – Part 3
- Foundations of Interstellar Studies Workshop
- Statement of Solidarity for The Interstellar Vision
- Opening of the i4is HQ
Issue 17 | May 2017
This issue features –
- Advanced Ion Propulsion Systems for Interstellar Precursor Probes
- Interstellar News
- News Feature: TRAPPIST-1
- Is the Alcubierre Drive the answer to Interstellar Travel?
- Album Review: Infinity of Space
- Book Review: Starlight, Starbright: Are Stars Conscious?
- Engineering New Worlds: Creating the Future
- Poster Feature: Space Resource Law
Issue 16 | February 2017
This issue features –
- Project Starshot
- Interstellar News
- Letter to the Editor : Stephen Ashworth
- ISU Masters Degree Projects – the i4is contribution
- Film Reviews: Arrival and Passengers
- Book Review: Star Ark : A Living Self-sustaining Spaceship
- Interstellar Challenge for London Schools 2016
- Image Feature: Artificial Intelligence Probes for Interstellar Exploration and Colonization
Issue 15 | November 2016
This issue features –
- Guest introduction by Nick Kanas, The Psychology and Sociology of Interstellar Travel
- News from the Initiative
- i4is/ISU 2016: Space Environment & Spacecraft Systems Engineering
- Daedalus: Model and Art
- The Andromeda Study
- Book Review: Gypsy: Carter Scholz
- The art and imagination of David A Hardy
Issue 14 | August 2016
This issue features –
- Guest introduction by Paul Gilster
- News from the initiative
- Cosmos: A Personal Voyage
- The BIS Daedalus Model – the last lap
- The Starship Engineer Course 2015
- Interstellar Studies at the ISU 2016
Issue 13 | May 2016
This issue features –
- Guest introduction by Kieran Twaites
- News from the initiative
- The 1,000 Year Starship
- Sending Ourselves to the stars? – 2
- Photo Feature: BIS Daedalus Starship Model
- Project Icarus: Introduction
Issue 12 | February 2016
This issue features –
- Guest Introduction
- News from the initiative
- Sending Ourselves to the Stars
- Starship Engineer
- Prototyping Starships
- Dragonfly: The Way Forward
- Film Review: Star Wars – The Force Awakens
Issue 11 | November 2015
This issue features –
- Stop Press: Starship Engineer Course
- Guest Introduction: Photometric SETI
- News: Project Dragonfly, i4is at SDSO, Axiom, Starship Congress
- Project Dragonfly Competition
- Interstellar Implications of the New Horizons Probe
- Starship Congress 2015
- TWIW 2014: i4is SF design Workshop
- TWIW 2014: Field Report
- What we did at Eastercon
- Film Review: The Martian
Issue 10 | August 2015
This issue features –
- News, Dragonfly, Pluto and Dysprosium
- Wormholes Come to London (2)
- Wormholes – Stargates to the Cosmic Neighbourhood
- i4is Goes Stratospheric
- Icarus Interstellar: Project Voyager
- What we did at the WorldCon (2)
- How do we Survive on a Distant World?
- What’s in Principium 11
Issue 9 | May 2015
This issue features –
- Project Dragonfly
- Kickstarter
- Introduction
- Beyond the Boundary – An i4is Book
- Educational Academy
- Technical Research Committee
- i4is and ISU
- Wormholes Come to London
- Film & Book Review “Interstellar”
- Merchandise
- News from the i4is
- What we did at the WorldCon
- What’s in Principium 10
Issue 8 | July 2014
This issue features –
- Introduction by Kelvin F. Long
- News from the Initiative
- Advances
- Community News
- Son of Daedalus
- Building Daedalus
- Book Review
Issue 7 | December 2013
This issue features –
- Introduction by Sarah Margree
- News from the initiative
- Voyager 1 Leaves the Heliosphere
- The New Horizons Message Initiative
- Project Icarus Workshop
- The Alpha Centauri Prize
- Starship Cities
- Enzmann Starships
Issue 6 | August 2013
This issue features –
- Introduction by Keith Cooper
- A Year I the Life of i4is
- Why an initiative now?
- The i4is Academy
- Gravity and the Apple
- The Origins of Future Worlds
- The Philosophy of the Starship
- Project Dragonfly
Issue 5 | July 2013
This issue features –
- Introduction by Keith Cooper
- News from the initiative
- Community
- Advances
- The Art of Music
- Jon Lomberg’s Starship Adventures
- Retrospective: SETI
Issue 4 | April 2013
This issue features –
- Introduction by Adrian Mann
- News from the initiative
- Tennessee Valley Interstellar Workshop
- Advances – DE-STAR
- The Starship Art of Jon Lomberg
- Book Review
Issue 3 | February 2013
This issue features –
- Introduction by Gregory Matloff
- Advances – Asteroid Propecting
- Advances – Skylon
- ‘Listening Post’
- A Learning Experience
- Retrospective: Bussard Ramjet
- Reviews
Issue 2 | January 2013
This issue features –
- Letter from Rob Swinney
- News from the initiative
- ‘Advances’
- Meet the Neighbours
- Retrospective: Voyager
- Reviews
Issue 1 | December 2012
This issue features –
- Letter from the Director
- News from the initiative
- ‘Advances’
- CubeSats
- Retrospective: Daedalus
- Book Reviews