Imagery. NASA Blue Marble: Next Generation, December 2004. The source file, URL, SHA-256 checksum, crop bounds, plotted coordinates, output checksum, and transformations are retained in the publishing manifest.
Interpretation. Modern imagery supplies terrain orientation only; it does not prove historical routes or boundaries. Straight-line distances are orientation measures; historical travel depended on road, terrain, water, weather, season, baggage, security, political permission, and waiting.
Use. NASA is credited as the imagery source and does not endorse this edition. Historical routes, labels, keys, travel notes, and uncertainty language are separate Zyel editorial overlays.
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