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Orrery i18n Style Guide

Translator brief — applies to every language. v0.1 · May 2026

Required reading before translating any locale. Authority for terminology decisions; updates here trigger re-translation of affected files (per ADR-033 §implementation-notes).


How to use this guide

You are translating Orrery into a new language. Before you start:

  1. Read §1 Universal symbols — these are never translated. Use the symbol literally in every language.
  2. Read §2 Proper nouns — transliterate per local convention only; do not translate.
  3. Use §3 + §4 as a binding glossary. The accepted-convention column for your language is the source of truth; pick from the column rather than translating the English literally.
  4. If your language column is empty (you're the first translator for it), populate it as you go and submit those decisions for review with the translation pass.
  5. Citation column points at the source authority for the term (ESA glossary, NASA Spanish-language style guide, JAXA glossary, etc.). Cite where possible; defer to authoritative sources over LLM judgement.

Files you will be touching:

  • messages/<code>.json — Paraglide UI strings (~276 keys; informal register where the en-US source uses a friendly tone).
  • static/data/i18n/<code>/missions/{mars,moon}/*.json — 36 mission overlay files. Translate name (display name), description, first (claim-to-fame), type (e.g. LANDER · FLOWN), events[].label, events[].note. Keep mission id and proper nouns intact.
  • static/data/i18n/<code>/{planets,rockets,sun,scenarios,earth-objects,moon-sites}/*.json — same overlay pattern, smaller files.

Per ADR-017's fallback chain, any key you omit will fall back to en-US — broken translation is bounded, not user-blocking.


§1 Universal symbols (NEVER translated)

These render as the symbol in every language. A native-language gloss is allowed on first use only if helpful for non-technical readers.

SymbolWhat it meansNotes
Δv (delta-v)Change in velocity, the standard mission-energy budgetUniversal across every space agency's literature
IspSpecific impulse (rocket engine efficiency)Universal abbreviation; spelled out as needed in editorial prose
C₃Characteristic energy (escape-trajectory energy)Universal symbol
AUAstronomical UnitEnglish / Japanese / Mandarin use AU; Spanish / French / Portuguese / Italian use UA; document per-language column below
gEarth surface gravity (9.81 m/s²)Universal

Numeric units (km, s, kg, N, K, etc.) are never translated — they are SI. Number formatting (1,000.5 vs 1.000,5) is handled by Intl.NumberFormat and is automatic per locale; translators never format numbers in strings.


§2 Proper nouns (TRANSLITERATE only — never translate)

Scientist surnames (transliterate per language convention)

EnglishNotes
Hohmann (transfer)Walter Hohmann
Tsiolkovsky (equation)Konstantin Tsiolkovsky
Lagrange (point, L1–L5)Joseph-Louis Lagrange
Lambert (problem, solver)Johann Heinrich Lambert
Kepler (laws, orbit)Johannes Kepler
Oberth (effect)Hermann Oberth
Newton (laws, units)Isaac Newton

Mission proper nouns (KEEP IN ORIGINAL — do not translate or transliterate)

Rationale: missions are real-world objects with single canonical names. A user searching for "Curiosity" in Spanish documentation should still find "Curiosity", not "Curiosidad".

MissionOriginal
All NASA Mars roversCuriosity, Perseverance, Sojourner, Spirit, Opportunity (English; keep)
Apollo programmeApollo 11, Apollo 17, Artemis II, Artemis III (keep numerals + name)
ISROChandrayaan-1, Chandrayaan-3, Mangalyaan / Mars Orbiter Mission (keep both names where dual-named)
CNSATianwen-1, Chang'e 4 / 5 / 6 (keep apostrophes + numerals)
JAXAHayabusa, SLIM (keep romanisation)
RoscosmosLuna 9 / 17 / 24, Mars 3 (keep)
ESAMars Express (keep)
MBRSC (UAE)Hope Probe (keep English; "مسبار الأمل" is acceptable in Arabic editorial prose only)
SpaceXStarship (keep)
Blue OriginBlue Moon MK1 (keep)
Tito conceptInspiration Mars (keep)

Agency proper nouns (KEEP IN ORIGINAL acronym)

NASA, ESA, JAXA, ISRO, CNSA, ROSCOSMOS, UAESA, AEB, KARI, CSA, UKSA, ASI, DLR, CNES, MBRSC. Do not expand or translate the acronyms.


§3 Translatable astronomy + orbital-mechanics terms

The English column is the source. The accepted-convention column for your target language is the binding translation. Cite source where given.

Englishes (Spanish)frdept-BRitsr-Latnsr-CyrlSource
aphelionafelioRAE
perihelionperihelioRAE
apogeeapogeoRAE
perigeeperigeoRAE
eccentricityexcentricidadRAE
true anomalyanomalía verdaderaESA Spanish glossary
line of apsideslínea de los ápsidesESA Spanish glossary
free-return (trajectory)trayectoria de retorno libreNASA-MSFC Spanish
sphere of influence (SOI)esfera de influenciaESA Spanish glossary
porkchop plotdiagrama porkchop (no Spanish equivalent in wide use)ESA Spanish glossary uses English
Astronomical Unit (AU / UA)UA (unidad astronómica)UAAE (Astronomische Einheit)UAUAIAU

Empty cells are populated by the translator for that language ticket.


§4 Translatable mission-domain terms

Englishesfrdept-BRitSource
launch windowventana de lanzamientoNASA-JPL Spanish
transit (cruise phase)tránsitoESA Spanish
flybysobrevueloESA Spanish
orbit insertioninserción orbitalESA Spanish
LOI (lunar orbit insertion)inserción en órbita lunar (IOL)NASA-MSFC Spanish
MOI (Mars orbit insertion)inserción en órbita marciana (IOM)ESA Spanish
EDL (entry, descent, landing)EDA (entrada, descenso, aterrizaje)NASA-JPL Spanish
TLI (trans-lunar injection)inyección translunar (ITL)NASA-MSFC Spanish
TMI (trans-Mars injection)inyección transmarciana (ITM)ESA Spanish
TCM (trajectory correction manoeuvre)maniobra de corrección de trayectoria (MCT)NASA-JPL Spanish
splashdownamerizajeRAE
rendezvousacoplamiento (when docking) / encuentro (when proximity)ESA Spanish
heliocentricheliocéntricoRAE
cislunarcislunarNASA-MSFC Spanish

§5 Tone + register guidance

  • Educational, friendly, precise. Orrery is for the curious learner first; physics accuracy second. Translations should match that register.
  • Informal "you" where the language distinguishes (Spanish , French tu, German du). The English source uses friendly direct address.
  • Active voice preferred over passive where the language allows naturally.
  • Concise — Spanish runs ~30% longer than English; tighten where possible to avoid layout overflow at 375px.
  • Date formatting is handled by Intl.DateTimeFormat (locale-aware). Do not translate dates in strings.
  • Number formatting handled by Intl.NumberFormat. Do not translate numbers in strings.

§6 Source authorities

When a term is contested, defer in this order:

  1. The space agency's own glossary in the target language (ESA Spanish, NASA-JPL Spanish, JAXA Japanese, CNSA Mandarin, etc.).
  2. The country's national language academy for general scientific vocabulary (RAE for Spanish, Académie française for French, Duden for German, Crusca for Italian, Academia Brasileira de Letras for pt-BR).
  3. Wikipedia in the target language as a tertiary tie-breaker — useful for confirming widespread usage but not authoritative.
  4. LLM judgement as final fallback when no authority exists. Document the choice in a comment and surface for review.

Cited source links (populate per language as glossaries are consulted):

  • ESA Spanish glossary: https://www.esa.int/Space_in_Member_States/Spain (general portal; search for "glosario")
  • NASA-MSFC Spanish technical reports: NTRS search by language:Spanish
  • NASA-JPL Spanish-language editorial guidelines: internal; cite via the specific PDF when quoted
  • IAU resolutions on astronomical unit: https://www.iau.org/static/resolutions/IAU2012_English.pdf
  • RAE diccionario: https://dle.rae.es/

§7 What to do when stuck

  • Term not in this glossary. Translate per language convention; add a row to §3 or §4 with the chosen term and a citation.
  • Conflicting conventions across sources. Pick the agency glossary over the language academy; document the conflict in a one-line note.
  • English term has no equivalent. Keep the English term and add an inline gloss on first use (e.g. porkchop plot in Spanish editorial prose).
  • Mission name conflict (e.g. agency uses one romanisation, Wikipedia uses another). Defer to the agency's official romanisation.

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