Principium Preprints

Collections of articles due to be published in upcoming issues of our quarterly, Principium. The articles you find here are made available exclusively to our members before they are made freely available.

Early access to Principium articles is one of perks of being a member. To view these preprints, please sign up for i4is membership.

Title	Author	Added
The Journals	Davies, J	2024-04-22
Biological intelligence vs AI - and the Fermi Paradox	Davies, J	2024-04-22
Our fifth Skateboards to Starships workshop	Davies, J	2024-04-22
Glasgow 24 SF Worldcon - An i4is update	Davies, J	2024-04-22
Book Review: Contact with Extraterrestrial Intelligence and Human Law	Gamtkitsulashvili, K and Manukonda, B	2024-04-22
IRG23: Applications and Design Guidelines for High Power Lasers	Gahan, D	2023-11-07
IRG23: Infrastructure Development Leading to the First Long-Duration Interstellar Probe	Davies, J	2023-11-07
IRG23: Silence is Golden: SETI and the Fermi Paradox	Wardman, M	2023-11-07
i4is at the Royal Institution 2023 - our fourth year	Davies, J	2023-11-07
IRG 23: X-ray and γ-ray Beam Interstellar Communication and Implications for SETI	Milne, P	2023-11-07
IRG 23: The Linguistics of Arrival, Universal Grammar and Interstellar Communication	Cranston, A	2023-11-07
The i4is members' page	Singh, P	2023-04-30
Project Lyra: What SpaceX could do: The Way to Go and the Launcher to Get There	Hibberd, A	2023-04-30
Cost-Optimal System Performance Maps for Laser-Accelerated Sailcraft	Hibberd, A	2023-04-30
IRG23 Preview: 8th Interstellar Symposium, McGill University, Montreal, July 10 – 13, 2023	Davies, J	2023-04-30
Searching for Alien Messages to a Nearby Star	Swinney, R	2023-02-04
IAC22 The Interstellar Presentations - part 2	Davies, J	2023-02-04
Volunteering Poster	i4is	2023-02-04
Book Review: Life in the Cosmos	Hein, A	2022-08-07
Two Equations to the Stars - Part Two: The Photon Sail Equation	Davies, J	2022-07-22
IAC 2022: The Interstellar Papers	Davies, J	2022-07-11
P37: Interstellar News	Davies, J	2022-05-02
Two Equations to the Stars - Part One: The Rocket Equation	Davies, J	2022-05-02
Finding new ways to share resources in space	Daniels, M	2022-05-02
The Tsiolkovsky Rocket Equation: A Parallel Derivation	Hay, A	2022-05-02
A brief on IAC2021: Inspire, Innovate and Discover For the Benefit of Humankind	AbdelFattah, S	2022-01-25
The Icarus Firefly Downlink	Davies, J	2022-01-25
7th Interstellar Symposium - The Hallway is More Important than the Podium...	Meany, J; Leahy, B	2022-01-25
Design of Interplanetary Missions to Jupiter Using Optimum Interplanetary Trajectory Software	Hibberd, A	2022-01-25
Optimal Strategies for Exploring Near-by Stars	Lebert, J	2021-08-15
2014 UN₂₇₁ Spacecraft Missions	Hibberd, A	2021-08-03
72nd International Astronautical Congress 2021: The Interstellar Papers	Davies, J	2021-07-18
News Feature: Mission to 2014 UN271 using OITS	Davies, J	2021-07-08
Practicalities and Difficulties of a Mission to 'Oumuamua	Hibberd, A	2021-05-07
Worldship and self replicating systems	Lamontagne, M	2021-02-07
The Artemis Accords: what comes after the Moon?	Daniels, M	2021-02-07
AMiTe Treffpunkt — A proposal for communication between Kardashev Type IIb civilisations	Gahan, D F	2021-01-31
The Interstellar Objects and Sample Returns	Hibberd, A	2020-10-31
Book Review: Extraterrestrial Languages by Daniel Oberhaus	Davies, J	2020-10-31
The Interstellar Downlink: Principles and Current Work	Davies, J	2020-10-31
News Feature: The 2020 ISU Masters Elective Module: Part 2	Davies, J	2020-10-31
News Feature: Breakthrough Starshot Communications Workshop	Kennedy III, R G	2020-10-31
The Stars: Humanity’s Destination	Bennett, G L	2020-08-20
Interstellar News	—	2020-08-20
IAC 2020 — Timetable of Interstellar Papers	—	2020-08-20
News Feature: The 2020 ISU Masters Elective Module	Davies, J	2020-08-20
Implications for an Interstellar World-ship in findings from the BIS SPACE Project	Soilleux, R	2020-08-20
Cassidy Cobbs - Bioscientist	Kennedy, R. & Davies, J. I.	2020-05-20
The i4is Members Page	—	2020-05-08
Become an i4is member	Mahon, P	2020-05-08
Freeman Dyson (1923-2020)	Hein, A	2020-05-08
The Interstellar Ram Jet at 60	Jackson, A A	2020-05-07
Note on use of Wikipedia	Davies, J. I.	2020-05-06
News Feature: IAC: The Interstellar Papers – Part 1	Davies, J. I.	2020-05-06
Rings around earth-like exoplanets as possible artificial megastructures	Novoseltsev, D.	2020-05-06
BOOK REVIEW: The Contact Paradox: Challenging our Assumptions in the Search for Extraterrestrial Intelligence	Mahon, P	2020-02-26
News Feature: IAC: The Interstellar Papers – Part 2	Davies, J. I.	2020-02-26
What Do We Really Know About The Outer Solar System?	Sutton, P.	2020-01-12
The Equation used in the Benkoski Paper: A Derivation	Hibberd, A	2020-01-12
News Feature: TVIW's 6th Interstellar Symposium and Advanced Interstellar Propulsion Workshop	Meany, J.	2020-01-12
How low can you go? - The Benkowski equation	Hibberd, A. & Davies, J. I.	2019-11-17
News Feature: IAC: The Interstellar Papers – Part 1	Davies, J. I.	2019-11-17
On a possible future direction for optical SETI	Novoseltsev, D.	2019-11-17
Timetable of Interstellar Papers (IAC)	—	2019-08-01
Competition RESULT	—	2019-08-01
The State of the Art in Fusion Propulsion	Schillo, K.	2019-08-01
News Feature: The Membership Team	Davies, J. I.	2019-04-04
Fine Tuning our Lasers: Updates on Project Dragonfly and Glowworm	Fries, D.	2019-04-04
Précis of progress & activity by i4is-US	Kennedy III, R. G.	2019-04-04
News Feature: IAC 2018 Special Session - Swarm Systems	Davies, J. I.	2019-04-04
News Feature: All Comets Great and Small	Davies, J. I.	2019-04-04
Territory in Outer Space	Daniels, M.	2019-02-02
The TVIW Power of Synergy Symposium: Promoting a Grand Transformation	Rather, J. D G	2019-02-02
Amerigo: Brief Overview of a 1000 AU probe study	Bockett, J.	2019-02-02
Project Glowworm: Testing Laser Sail Propulsion in Low Earth Orbit	Burkhardt, Z.	2019-02-02

= Awaiting publication
= Published

The articles available here may differ from the final published articles.

A Precursor Mission to Proxima Centauri

31 October 2024

A Mission to Five Near Earth Objects in 2030 Adam Hibberd We at i4is, together with our collaborators on the Phase I NIAC (NASA Innovative Advanced Concepts) at Space Initiatives Inc., have been contemplating precursors to the ultimate mission of sending laser sails to swarm our nearest neighbouring star, Proxima Centauri. A summary of the […]

Deflecting Apophis

26 October 2024

Adam Hibberd There have been some developments. I have been addressing the problem of how to deflect Apophis from its path if it were indeed on a collision course with Earth. My Apocalypse Plot gives the magnitude of ΔV at different points in Apophis’s orbit to send it on a course to JUST strike the […]

Apophis: More Monolythical Mathematical Musings.

29 September 2024

Adam Hibberd Apophis gets awfully close on Friday April 13th 2029 (within GEO altitude). Its orbit is altered by the encounter with Earth and the obvious question is will there be any further possible encounters? Some of you may remember I have worked on the practicalities of sending laser-accelerated sails to intercept Apophis as it […]

Errors in Velocity Due to an Interstellar Probe’s Fast Encounter with a Star

23 July 2024

Adam Hibberd A spacecraft is travelling on a very hyperbolic orbit w.r.t. an object X (possibly a star) which has gravitational mass, μ, meaning the spacecraft is only slightly deflected from its direction of motion. Our task is to quantify the errors in velocity, both longitudinal and transverse, associated with this encounter compared to simply […]

‘Oumuamua: Lasers in Space

16 May 2024

Adam Hibberd In my latest research, I have been considering the case of using laser structures in space to accelerate space laser sails to sufficient speed so that they will ultimately reach the first discovered interstellar object, 1I/’Oumuamua, within a matter of years from launch, or even as soon as a year. This is clearly […]

Measurement of Mass by Space Sails

16 February 2024

Adam Hibberd I’ve been doing a little algebra. Let me state the problem. Let us say we have a swarm of space sails flying edge on to the interstellar medium (ISM). This swarm lies in a plane at right angles to its velocity relative to this ISM. Now lets bring in an element of the […]

Project Lyra Mission Guide

26 January 2024

Adam Hibberd I provide for you a chart of some missions to 1I/’Oumuamua investigated by Project Lyra. The green rows use chemical propulsion, the blue use nuclear thermal propulsion (NTP) and the pink exploit laser sails. This table will be updated when new research becomes available. For more detail, zoom in with your mouse (Ctrl+scroll […]

Project Lyra: A Solar Oberth at 10 Solar Radii

5 January 2024

Adam Hibberd I have recently returned my attention to the Solar Oberth mission to ‘Oumuamua. For readers not familiar with this celestial body, 1I/’Oumuamua was the first interstellar object to be discovered passing through our Solar System, is now out of range of our most powerful telescopes and has left scientists with many questions in […]

Swarming Proxima

20 November 2023

Adam Hibberd Breakthrough Starshot is the Initative to send a probe at 20% light speed (0.2c) to the nearest neighbouring star Proxima Centauri. But how do we achieve such a high speed? It turns out that if we have an extremely powerful laser (and exponential advances in tech over the next decades will mean that […]

Laser and Sail in Earth Orbit with Evolutionary Neurocontrol

24 October 2023

Adam Hibberd In my last post I explained how my software development, Optimum Interplanetary Trajectory Software (OITS), seems to achieve miracles of intelligent design in a fashion analogous to evolution, though in fact with both cases evidently no intelligence is involved – instead simple mechanisms combined with iteration are at work. This concept stimulated me […]

OITS Takes on Evolution

10 September 2023

Adam Hibberd The more I think about evolution through natural selection the more I see analogues to my software development Optimum Interplanetary Trajectory Software. (I should make it clear at this early stage in my post that OITS does NOT employ a genetic/evolutionary algorithm approach, I shall elucidate below.) You see there is NO intent […]

How Close did ‘Oumuamua Approach Each of the Inner Planets?

2 September 2023

Adam Hibberd A view of the distance of ‘Oumuamua from each of the Inner Planets as it rounded the sun, reached perihelion and then sped away again. Mars was just about as far away as it could possibly have been from ‘Oumuamua. ‘Oumuamua came very close to Earth (around 0.16 au). It came no closer […]

Was Loeb’s Bolide Interstellar?

1 September 2023

Adam Hibberd Loeb’s interstellar spherules have caused controversy and indignation amongst experts in the science community. For those of you not-in-the-know, Loeb travelled to the site of a proposed interstellar meteor (his designation: IM1) which he had identified in a catalogue of bolides held by NASA and then discovered in the ocean tiny metallic blobs he […]

‘Oumuamua – a Sci-Fi Story or Reality?

23 August 2023

Adam Hibberd Let me tell you all a story. It is the story of life and its purpose. I ask you to bear with me here as Project Lyra and ‘Oumuamua will make an appearance eventually – I promise. Many of you will be familiar with the idea that the universe might be some kind […]

‘Oumuamua: The Mystery Unfolds

20 August 2023

Adam Hibberd Those of you who have been following my Project Lyra blogs know that I have over the past year or so done some extensive analysis of ‘Oumuamua’s trajectory. You may refer to previous posts on the i4is website to get an understanding of exactly what I have been up to, or alternatively continue […]

Psyche: OITS has Something to Say

18 August 2023

Adam Hibberd Here’s a mission to asteroid Psyche for you. Initial theories favoured Psyche as a core of a failed protoplanet, containing vast reserves of metals. More recent research, however favour alternative origin theories. Whatever is the case, we are about to discover its true nature and this would be a huge step forwards for […]

Project Lyra: Ignore the outlier and miss an opportunity

31 July 2023

Adam Hibberd Wouldn’t you like an answer to the question: What is ‘Oumuamua? There have been many theories, but there is no real consensus. The only way to answer this would be to send a spacecraft to observe ‘Oumuamua in situ but the total lack of will-power to get this question answered, in my view, […]

The Case of Fireball CNEOS 2017-10-09

28 July 2023

Adam Hibberd Around the middle of last year I read an article by Siraj and Loeb in which they analysed closely a database of bolides (which are meteor fireballs) maintained by NASA-JPL CNEOS (Center for Near Earth Object Studies). In so doing they identified at least one bolide as having an interstellar origin (designated CNEOS […]

Project Lyra: The Mission to Resolve a Mystery

4 July 2023

Adam Hibberd Project Lyra is the study of the feasibility of a spacecraft mission to the first interstellar object to be discovered passing through our Solar System, designated 1I/’Oumuamua. I have now authored and co-authored a total of nine Project Lyra papers. The considerable number of science papers (many now peer-reviewed, several still to be […]

Optimum Interplanetary Trajectory Software: The Secrets Revealed

25 June 2023

Adam Hibberd In the UK Spring of 2017, I derived the theory for solving interplanetary trajectories, which enabled me to develop a powerful software tool for optimising hight thrust spacecraft missions, a tool which I called Optimum Interplanetary Trajectory Software (OITS). For those of you fascinated by mathematics, in particular mathematical formulae, the two equations […]

Laser Sails: Trajectories Using Optimum Interplanetary Trajectory Software

16 June 2023

It struck me a while ago that I have developed this extremely effective tool for solving interplanetary trajectories (OITS), so how would I be able to exploit it for alternative applications – applications which would be beyond its originally intended purpose, that of designing trajectories for chemically propelled spacecraft (and in the process assuming impulsive […]

Mars Ride-Share: an Opportunity Not to be Missed

14 June 2023

Adam Hibberd I was recently discussing with my colleagues across the pond, the potential for mounting a cheap mission to some alternative, yet interesting destination in the inner Solar System, by exploiting a ‘ride-share’ with a more important mission, possibly one organised by NASA or ESA. It struck me that since there have been, and […]

C/2014 UN₂₇₁ the comet which will NOT collide with the Earth

4 April 2023

Adam Hibberd An Oort cloud comet is composed primarily of dust and ice and has spent most of its life in the far-flung distant reaches of our Solar System (2,000 au to 200,000 au from our Sun). It is eventually nudged inward towards our Sun by gravitational influences such as galactic tides or some passing […]

Project Lyra: Falcon Heavy Expendable

27 March 2023

Adam Hibberd Following on from my previous blog where I studied the capability of the up-coming Ariane 6 4 launcher in terms of delivering a spacecraft on a course to intercept the first interstellar object to be discovered, ‘Oumuamua, I continue this logical progression with analysis of a more powerful launcher, the Falcon Heavy. The […]

Project Lyra: Using an Ariane 6

16 March 2023

Adam Hibberd Ariane 6 is the up-and-coming successor to the old Arianespace workhorse, Ariane 5, and may secure its maiden flight later this year. There will ultimately be two strap-on booster configurations from which to choose, one with two boosters, and the more powerful version with four. I thought it might be worthwhile assessing the […]

Optimum Interplanetary Trajectory Software (OITS)

15 February 2023

Adam Hibberd I started development of this software, OITS, in April 2017 on a holiday near the little town of Cheadle, in the county of Staffordshire, UK. I started from the very basics, deriving the theory during the holiday and continuing shortly thereafter, and then immersed myself in the implementation of the equations I had […]

Music of ‘Oumuamua

30 January 2023

Adam Hibberd If you have a fascination for the mysterious interstellar object ‘Oumuamua and are musically inclined, please check out these two pieces by my musician friend Robin Jax based on recordings of me playing two piano compositions of mine. Whether it be Robin’s neurodivergence, or my own schizophrenia, we have both overcome our respective […]

Things to Come

22 January 2023

Adam Hibberd I sometimes wonder at the short-sightedness of people. The sort of people who scoff and scorn at the far-sighted work which most of my work colleagues and I have dedicated a good deal of our lives to pursue, largely voluntarily. They may argue: We have such and such a problem NOW, how are […]

Project Lyra: Using Jupiter Alone to get to ‘Oumuamua

9 January 2023

Adam Hibberd Here is a ‘pork chop plot’ of missions to ‘Oumuamua using a Jupiter powered gravitational assist (or a Jupiter Oberth Manoeuvre, JOM). Refer to the Figure (1). Essentially, what we have are three coordinates where firstly the horizontal axis shows the launch date, the vertical axis shows the flight duration, and for every […]

‘Oumuamua: The State of Play

30 December 2022

Adam Hibberd In 2017, an interstellar object was discovered, the first ever to be detected. It was observed by the Hawaiian observatory Pan-STARRS, subsequently studied by many telescopes before disappearing into the distance in January 2018. An estimate on the number density, N (how many per unit volume), in interstellar space was determined based on […]

Why the Stars?

24 November 2022

Adam Hibberd November 2022 People may ask the question why we should venture beyond our solar system to explore the stars? Why should we commit precious resources to such an endeavour? I have an answer to this which may to some degree be a personal one. The question boils down to why are we curious? […]

Exploring ‘Oumuamua’s Trajectory – Further Notes

9 November 2022

Adam Hibberd November 2022 In my last blog I reported the progress of my work regarding the intriguing little conundrum of the first interstellar object (ISO) to be discovered, designated ‘Oumuamua, in particular my research into its orbit. In fact ‘Oumuamua is puzzling on many counts and I have also in a previous blog elaborated […]

Exploring ‘Oumuamua’s Perihelion Date

31 October 2022

Adam Hibberd October 2022 This blog may be a bit cheeky but do take heed of the last line before jumping to any conclusions! I’ve been mucking around with ‘Oumuamua’s orbit on my computer lately. Mucking around in the sense of playing with its orbital parameters and seeing what crops up. Those of you who […]

Presentation for the British Interplanetary Society on Missions to 2024 YR4

8 April 2025

Adam Hibberd An asteroid was discovered in December 2024 which for a while had the world on tenter hooks. Its predicted path brought it in close proximity to the Earth in December 2032, with a chance of collision which steadily rose to around 3% over the course of several weeks. Now all the pressure valves […]

The Importance of Exploration

2 April 2025

Adam Hibberd I have recently read a review of a book titled “Astrotopia: the Dangerous Religion of the Corporate Space Race” written by a professor Mary-Jane Rubenstein and it is reviewed by Patrick Mahon, who is on the Board of Directors for i4is. The review can be found here. You might be interested in that […]