F - Sources, Notes & Bibliography
General Sources
Astronomical quantities in the narrative are rounded for general readers and primarily draw on NASA and JPL reference material. The technical verification described in the associated research record used the authenticated JPL DE440 planetary ephemeris and official CSPICE for planetary crossing and phase checks. The nineteen-body historical asteroid screen used a 2010 CODES asteroid SPK associated with DE405-era orbit dynamics; the archived asteroid trajectories were evaluated with a DE440 planetary/Sun reference and must therefore be treated as a mixed-model diagnostic. Approximate small-body elements were additionally checked against JPL small-body reference material. Contemporary Horizons solutions for all nineteen bodies, and associated observational-uncertainty certification, have not been executed. The bounded results must not be described as contemporary asteroid validation.
The Solarian calendar structures, Repeat Factors, synchronized and independent regimes, whole-week quantisation, expansion-joint logic, Solarian Week Index, implementation profiles and month-gap heuristic are original elements of the Solarian architecture developed in this book. Their formal definitions and calculations are documented in Appendix A, the subsequent technical appendices and the separate Solarian Technical Record v1.0.
The standard Solarian civil day of 86,400 seconds uses the SI second as defined by the International System of Units.
Preface — Why an Operator Ended Up Designing a Solar System Calendar
The discussion of 4-4-5 and other whole-week business calendars reflects long-established accounting practice rather than a proposed Solarian innovation. United States tax rules, for example, explicitly recognise fiscal years constructed from 52 or 53 complete weeks.
The Marian Calendar and The Mars Codex are the author's earlier works and provide the personal and intellectual route into the present project. Solarian is technically independent of Marian.
Chapter 1 — When the Solar System Becomes Geography
The chapter is primarily a thought experiment about the institutional consequences of permanent multi-world settlement rather than a prediction of settlement dates. Descriptions of planets, moons and artificial habitats are developed in later chapters with their astronomical sources.
No claim is made that permanent settlement is inevitable or imminent. The premise of the book is conditional: if human civilisation becomes permanently distributed across multiple astronomical environments, new civil infrastructure questions follow.
Chapter 2 — One Planet Made It Look Easy
For general calendar history, astronomical cycles, the development of the Julian and Gregorian systems, the history of the week and the distinction between astronomical and conventional calendar units, see E. G. Richards, Mapping Time: The Calendar and Its History, and Nachum Dershowitz and Edward M. Reingold, Calendrical Calculations.
The discussion of 52–53-week fiscal years reflects established accounting practice; see United States Internal Revenue Service, Publication 538: Accounting Periods and Methods.
The estimate that more than seventy authors had published Martian timekeeping proposals over approximately 125 years comes from Thomas Gangale and Marilyn Dudley-Rowley's 2005 review, “Issues and Options for a Martian Calendar.”
Josef Šurán's complete-week Martian calendar is described in “A Calendar for Mars” (1997). Thomas Gangale's Darian architecture is described in “The Architecture of Time, Part 2: The Darian System for Mars” (2006). Robert Zubrin's twelve unequal-duration, equal-orbital-angle Martian months appear in The Case for Mars (1996). Dennis V. Silin's twelve-month Exodus Calendar was published in the Journal of the British Interplanetary Society in 2025.
Gangale and Dudley-Rowley's earlier “The Architecture of Time: Design Implications for Extended Space Missions” is useful broader context for treating extraterrestrial civil time as a design problem rather than merely an astronomical conversion exercise.
The discussion of emerging lunar time standards refers to the United States Office of Science and Technology Policy's 2024 policy on celestial time standardisation, which called for a distinct lunar reference time traceable to UTC and scalable to other celestial environments.
Chapter 3 — What Must Be Shared
The ten requirements in this chapter are the author's design brief for Solarian. They are not presented as an established scientific standard or as the only possible requirements for extraterrestrial civil time.
The distinction between measurable engineering criteria and cultural or human-factors choices is deliberate. Later chapters therefore test mathematical properties directly while treating adoption, naming and cultural preference as empirical or political questions rather than calculable results.
Chapter 5 — The Calendar for People
The minth, mear and the separation of portable human operating time from local astronomical time are Solarian constructs introduced by the author.
The 86,400-second standard civil day is constructed from SI seconds. Mars is treated separately because its natural mean solar day remains close to the terrestrial human day.
The A–L minth identifiers are structural machine/reference labels, not proposed mandatory cultural names.
Chapter 6 — The Calendar for Worlds
Planetary orbital periods and broad orbital properties follow NASA/JPL astronomical data.
The common twelve-position astronomical calendar and common heliocentric reference direction are Solarian design choices. They are low-resolution civil representations of continuous orbital motion and are not substitutes for ephemerides.
The rule that major moons normally inherit the heliocentric calendar of their parent planetary system is likewise a Solarian civil-design rule, not an astronomical claim that local moon cycles are unimportant.
Chapter 7 — You Only Need One Number
The Repeat Factor, R, is original to Solarian.
The identity
R = minths per orbital month = mears per orbital year
follows from the deliberately matched twelve-position structures of the human and astronomical calendars. The mathematical coverage and boundary properties of the Repeat Factor are developed formally in the technical appendices and Solarian Technical Record v1.0.
Chapter 8 — The Week Does Not Break
Whole-week quantisation, the expansion-joint architecture, the Solarian Common/Leap parity convention and the Monday Rule are Solarian design choices.
Existing use of complete-week fiscal years provides terrestrial precedent for treating a week as a useful indivisible operating block, but Solarian's specific intercalation architecture is original to this work.
Chapter 9 — One Week for the Solar System
The Solarian Week Index (SWI) is original to Solarian. It is a civil interoperability coordinate rather than a scientific timescale.
Its epoch — SWI 1 beginning Monday, 10 April 1961 — is commemorative. That week contains 12 April 1961, the date of Yuri Gagarin's first human spaceflight. The epoch does not alter or reset the underlying weekday sequence.
Mars does not share the physical duration of a standard SWI week because its week contains seven Martian sols. Its local week therefore maps to the common chronology rather than being physically identical to a seven-standard-day SWI interval.
Chapter 10 — The Red Planet Is Almost Too Easy
Mars's sol length, orbital period and seasonal coordinate conventions are consistent with the Mars timing work of Michael Allison and Megan McEwen and NASA/JPL planetary data.
Allison and McEwen derive a mean Martian solar day of approximately 1.02749125 terrestrial days and provide a widely used treatment of areocentric solar longitude, Ls.
The R2 implementation, its 95/96-week civil years and the associated expansion-joint treatment are Solarian calculations rather than features of an existing Martian calendar.
Chapter 11 — One Calendar, Many Moons
Jupiter's orbital period, rotation and broad physical properties follow NASA reference data. Descriptions and local orbital periods of Io, Europa, Ganymede and Callisto follow NASA/JPL material on the Galilean satellites.
The decision to treat the major Jovian moons and habitats as one heliocentric civil-calendar system is a Solarian architectural choice. Local satellite orbital cycles remain physically meaningful and are not replaced by the Jovian year.
The R13 calendar and its intercalation are Solarian calculations.
Chapter 12 — Almost Perfectly In Sync
Saturnian planetary data and the broad physical descriptions of Titan, Enceladus and the other major moons follow NASA reference material.
The observation that Saturn's physical year lies unusually close to thirty-two nominal 48-week mears is an arithmetic consequence of those astronomical data. The R32 structure and its 1,536/1,537-week implementation are Solarian constructions.
Chapter 13 — The Generational Year
Uranus's orbital period, axial tilt and system characteristics follow NASA/JPL planetary data.
The R91 implementation and the resulting 365/366-week orbital-month coincidence are Solarian calculations. The numerical resemblance to terrestrial 365/366-day years is incidental and has no physical relationship to the Gregorian calendar.
Chapter 14 — Beyond a Human Lifetime
Neptune's orbital period, axial tilt and principal system properties follow NASA/JPL data. Descriptive material concerning Triton follows NASA planetary-science references.
The R179 structure, 8,598/8,599-week civil years and 716/717-week orbital months are Solarian calculations.
Chapter 15 — A Population, Not a World
Orbital elements for the Main-Belt population examined in this chapter derive principally from JPL's Small-Body Database and associated orbital-element data. Values in the narrative are deliberately rounded.
The grouping of the sample into R4, R5, R6 and R7 families is a Solarian classification generated by applying the Repeat Factor architecture to those orbital periods.
An author-ratified phase-fidelity criterion and a deterministic expansion-joint generator were used for a bounded archival test of nineteen main-belt bodies. The result is a historical screening, not a certified present-day Horizons orbit comparison or a ratification of all supplemental calendar forms. The complete ledger, exact source versions, 30°/45° policy and remaining scientific gates belong in the accompanying versioned technical record. The population is a test of architectural coverage, not a forecast of settlement destinations.
Chapter 16 — When We Get to Choose the Orbit
For the historical engineering context of large rotating artificial habitats, see Gerard K. O'Neill, “The Colonization of Space” (1974), and Richard D. Johnson and Charles Holbrow, eds., Space Settlements: A Design Study (NASA SP-413, 1977).
The specific R3 habitat used in this chapter is an illustrative Solarian design case. Its chosen heliocentric orbit and calendar relationship are not presented as O'Neill's or NASA's proposed calendar or as a prediction of an actual future settlement.
Chapter 17 — Where the Protocol Says No
Pluto's physical and orbital data derive from NASA/JPL sources. Its highly eccentric orbit ranges from roughly 30 to 49 AU from the Sun.
The candidate R270 arithmetic and the equal-time versus orbital-angle comparison are illustrative Solarian calculations. They motivate treating Pluto’s conventional twelve-month angular-phase proxy as a specialised case; no canonical Plutonian intercalation profile or complete contemporary uncertainty certification is implied.
Chapter 18 — The Calendar We Already Invented
Earth's orbital period is taken from standard astronomical references.
The R1 Earth calendar is explicitly a Solarian thought experiment, not a claim about the historical development of Gregorian or modern commercial calendars.
For the real-world use of 52–53-week fiscal years, see United States Internal Revenue Service, Publication 538: Accounting Periods and Methods. The familiar 4-4-5 family of operating calendars provides convergent terrestrial evidence for the practical usefulness of week-based periods and thirteen-week quarters; it is not claimed as a historical precursor from which Solarian was derived.
Chapter 19 — When the Two Calendars Separate
Venusian orbital period, rotation, solar-day duration, surface conditions and orbital eccentricity follow NASA planetary data.
The Independent regime is a Solarian design category. The 32/33-week astronomical year and the approximate 9:1 distribution of those year forms follow from whole-week representation of Venus's physical orbit.
The 48-week human mear remains independent by design.
Chapter 20 — The Fastest Year
Mercury's 87.97-day orbital year, approximately 176-day solar day and orbital eccentricity follow NASA planetary data.
The 12/13-week Mercurian astronomical chronology is a Solarian construction. The tested DE440 phase analysis found a maximum civil-month-start angular deviation of approximately 59°, beyond the 45° specialised-treatment threshold. The independently running human calendar and chronological orbital-year count remain valid in that tested model; the twelve-position phase display does not meet the standard phase metric.
Chapter 21 — What Changes When You Move?
The traveller in this chapter is illustrative. The examples combine implementation structures established in the preceding chapters to test cognitive portability.
“Portability comes from shared structure, not shared duration” is a Solarian design proposition rather than an empirical claim about future settlers. Human-factors testing would be required to determine how successfully actual users transfer between the proposed calendars.
Chapter 22 — Several Calendars, One History
The three-coordinate model — local civil date, common chronology and Solarian Week Index — is a Solarian interoperability proposal.
References to Gregorian date and UTC are examples of a plausible continuing common chronology, not a requirement that future civilisation retain the Gregorian era indefinitely.
The canonical machine-record architecture belongs to the Solarian specification and Technical Record.
Chapter 23 — Dates Become Geography
The circular month-gap heuristic and the phase-aware communications analysis are original Solarian results.
The underlying orbital states and light-time validation use JPL ephemeris data. Detailed methods, sample definitions, residuals and validation tables are contained in Appendix D and the Solarian Technical Record v1.0.
The heuristic is deliberately low resolution. It is not proposed for navigation, trajectory design or precision communications scheduling.
Chapter 24 — Knowing Where to Stop
This chapter distinguishes calculated properties of the architecture from questions requiring human-factors testing, governance or future institutional choice.
The proposed applicability boundaries, conformance requirements and versioning principles are developed more formally in the Solarian Protocol and Technical Record.
No claim is made that mathematical coherence demonstrates eventual adoption.
Chapter 25 — One Grammar, Many Calendars
This chapter is a synthesis of the architecture developed and tested in the preceding chapters.
“Common grammar; local culture” summarises the protocol's deliberate division between shared structural identities and locally determined language, holidays, traditions and civil meaning.
The cultural examples are illustrative rather than predictions.
BIBLIOGRAPHY
Allison, Michael, and Megan McEwen. “A Post-Pathfinder Evaluation of Areocentric Solar Coordinates with Improved Timing Recipes for Mars Seasonal/Diurnal Climate Studies.” Planetary and Space Science 48, nos. 2–3 (2000): 215–235. DOI: 10.1016/S0032-0633(99)00092-6.
Bureau International des Poids et Mesures. The International System of Units (SI). 9th ed., updated 2026. Sèvres: BIPM. DOI: 10.59161/AUEZ1291.
Bullock, Jonathan. Solarian Protocol v1.0: Normative Core Specification. 2026.
Bullock, Jonathan. Solarian Technical Record v1.0. 2026.
Dershowitz, Nachum, and Edward M. Reingold. Calendrical Calculations: The Ultimate Edition. 4th ed. Cambridge: Cambridge University Press, 2018. DOI: 10.1017/9781107415058.
Gangale, Thomas. “The Architecture of Time, Part 2: The Darian System for Mars.” SAE Technical Paper 2006-01-2249. SAE International, 2006. DOI: 10.4271/2006-01-2249.
Gangale, Thomas. The Darian Calendar for Titan. OPS-Alaska. Accessed 4 October 2026.
Gangale, Thomas, and Marilyn Dudley-Rowley. “The Architecture of Time: Design Implications for Extended Space Missions.” SAE Technical Paper 2004-01-2533. SAE International, 2004. DOI: 10.4271/2004-01-2533.
Gangale, Thomas, and Marilyn Dudley-Rowley. “Issues and Options for a Martian Calendar.” Planetary and Space Science 53, nos. 14–15 (2005): 1483–1495. DOI: 10.1016/j.pss.2005.07.012.
Jet Propulsion Laboratory. Horizons System. Solar System Dynamics, California Institute of Technology. Accessed 4 October 2026.
Jet Propulsion Laboratory. Small-Body Database and Small-Body Element Tables. Solar System Dynamics, California Institute of Technology. Accessed 4 October 2026.
Johnson, Richard D., and Charles Holbrow, eds. Space Settlements: A Design Study. NASA SP-413. Washington, DC: National Aeronautics and Space Administration, 1977.
National Aeronautics and Space Administration. Planetary Fact Sheet. NASA Space Science Data Coordinated Archive. Accessed 4 October 2026.
National Aeronautics and Space Administration. Solar System Exploration: Planet, Dwarf-Planet and Moon Fact Pages. NASA Science. Material consulted for Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto and principal moons discussed in the text. Accessed 4 October 2026.
O'Neill, Gerard K. “The Colonization of Space.” Physics Today 27, no. 9 (1974): 32–40. DOI: 10.1063/1.3128863.
Office of Science and Technology Policy. Policy on Celestial Time Standardization in Support of the National Cislunar Science and Technology Strategy. Executive Office of the President of the United States, 2 April 2024.
Richards, E. G. Mapping Time: The Calendar and Its History. Oxford: Oxford University Press, 1998. DOI: 10.1093/oso/9780198504139.001.0001.
Silin, Dennis V. “The Exodus Calendar: A Simple Timekeeping System for Martian Colonists.” Journal of the British Interplanetary Society 78, no. 9 (2025): 305–307. DOI: 10.59332/jbis-078-09-0305.
Šurán, Josef. “A Calendar for Mars.” Planetary and Space Science 45, no. 6 (1997): 705–708. DOI: 10.1016/S0032-0633(97)00033-0.
United States Internal Revenue Service. Publication 538: Accounting Periods and Methods. Washington, DC: Internal Revenue Service. Section on 52–53-week tax years.
Zubrin, Robert, with Richard Wagner. The Case for Mars: The Plan to Settle the Red Planet and Why We Must. New York: Free Press, 1996.