Eclipse Wayfinder data sources
The site combines NASA eclipse references, an open astronomical calculation engine, NASA POWER historical climate data and curated geographic/planning data. Each source has a defined job and stated limitations.
NASA GSFC eclipse data
NASA GSFC eclipse references provide event-level geometry and Besselian elements for both 2027 solar eclipses, plus the detailed August 2 path table used by the totality tools. Eclipse Wayfinder uses these references for validation and route targeting rather than scraping timings from another consumer website.
NASA February 6 annular-eclipse data · NASA August 2 path table
Astronomy Engine
Astronomy Engine is the MIT-licensed library used for local solar eclipse circumstances. It calculates the event for the observer coordinate and provides the foundation for Eclipse Finder, Totality Finder and Totality Gain.
NASA POWER historical climate
The climate pipeline requests a fixed August 2001–2025 climatology at every reference coordinate. It uses all-sky and clear-sky surface shortwave irradiance, 2 m air temperature and 2 m relative humidity. NASA POWER currently serves the solar fields at roughly 1° × 1° resolution and meteorological fields at roughly 0.5° × 0.625°. Those grids are much coarser than a city coordinate, so the values describe regional historical conditions rather than a particular hotel, beach or field.
Eclipse Wayfinder refreshes these records from NASA POWER and validates them before they are used in the climate layer. If a record cannot be retrieved or validated, the climate portion of the viewing score stays unavailable instead of receiving a substitute value.
NASA POWER climatology API documentation · NASA POWER API tutorial
Geographic place data
Published city guides currently use curated reference coordinates. GeoNames is the geographic source selected for broader place-name and coordinate discovery as that search layer expands. A place can be searchable in the calculator without needing a dedicated city guide.
Solar viewing safety
The American Astronomical Society and NASA provide the primary practical safety references. Eclipse Wayfinder links to those sources rather than certifying solar viewers itself.
AAS eye safety · NASA eclipse safety
Curated practical profiles
Accessibility, accommodation depth, relocation flexibility and viewing environment are curated structural baselines for published locations. They are not live travel advice. They do not represent current traffic, hotel prices, border policy, security conditions or future availability.
Source hierarchy and conflicts
A source is chosen for the job it is suited to do. Astronomy Engine produces coordinate-level circumstances. NASA eclipse material provides event and path references. NASA POWER provides regional historical climate. A travel claim needs a current official travel source rather than an astronomy dataset. When two values disagree, Eclipse Wayfinder first checks the coordinate, time standard, model assumptions and source date instead of averaging incompatible numbers.
Corrections and source updates
Broken links, changed source documentation or reproducible data differences can be reported to contact@eclipsewayfinder.com. Include the page URL and the source you believe should be checked.
How sources flow into tools
Read the methodology for the calculation pipeline and score weights, open the February annular guide, or use the August totality path page for the source data in context.
See the disclaimer for the limits of historical climate, travel information and calculated path boundaries.