Starchart is a sourced creative visualization, not a navigation instrument.
Original Starchart code is MIT licensed. Read the MIT licence.
The self-hosted Oxanium interface font is copyright the Oxanium Project Authors and distributed under the SIL Open Font License 1.1. No font CDN is contacted.
The default freezes the integer counts decoded from the fourteen historical binary inscriptions separately from modern catalogue periods. One is drawn perpendicular to the ray; zero is a separated dash parallel to it; fixed bit spacing makes inscription length follow bit count. Archive mode preserves historical false precision and uses map-derived signed angles and planar radial ratios instead of modern PSRCAT distance geometry. Johnston warns that these directions and distances were measured from a poor-quality diagram, so Starchart treats them as approximate reconstruction inputs rather than engraving-level precision.
The 1972 paper defines ray length as planar polar r and measures z inward from the ray’s far endpoint. Archive z combines map-derived r with stable Galactic latitude. The Galactic-center line establishes angular zero and planar distance scale: Archive uses the 8,500 pc reconstruction implied by Johnston’s normalized map measurements, while Computed uses the GRAVITY Collaboration’s 8,178 pc measurement. For Sol, its endpoint tick demonstrates z=0; an off-plane custom origin instead uses an inset origin-relative z tick, and hidden-z mode suppresses it. The mark is not binary. Linear scale preserves r/z ratios; square-root scale is a compressed, non-historical visualization. The intended asymmetric z tick encoded sign, but engraving execution breached that convention.
Visible tick lengths, map size and preview camera are presentation controls. At 100%, the proportional binary scale uses plaque-like spacing and crossbars roughly one third of the previous oversized rendering; it changes the complete inscription together without altering ray geometry. Labels and period visibility likewise never change ray geometry. The hydrogen transition constant remains in metadata and accessible descriptions, but the atom-state diagram is omitted because Starchart renders the map rather than the complete plaque.
Data are derived from ATNF PSRCAT v2.8.1, R. N. Manchester et al., AJ 129, 1993–2006 (2005), using CSIRO DAP collection v17, DOI 10.25919/mjwb-7w32, exact file ID 100508507, retrieved 2026-08-17.
Pulsar directions are generally measured precisely, but distances remain uncertain and model-dependent. Computed mode recalculates planar ray lengths using each record’s preferred available modern distance estimate; Archive preserves approximate early-1970s geometry reconstructed from the original inscription. Large differences between their ray lengths are expected and do not indicate a rendering error.
Source SHA-256: 29e423e5878d8b97e397425b6a1fe1529396a7b25909e3c1d56924641db6c63b. The exact data endpoint applies BSD 3-Clause licence ID 1241. Read the PSRCAT/CSIRO licence and disclaimer.
The small frozen origin registry is reconciled through A. Golovin et al., Fifth Catalogue of Nearby Stars (CNS5), and its GAVO service. CNS5 draws on Gaia EDR3 and the Hipparcos new reduction. Gaia/Hipparcos data carry ESA attribution and noncommercial terms. Values retain their source epoch; Starchart does not propagate epochs in v1.
