Data

Every moment Solmanac computes, 5,226 of them from 1900 to 2100, in one file. The same numbers the site shows, to the second.

CSVJSON

Columns

year, id, name

The year and the moment, e.g. great-earlysun, Great Earlysun.

instant_utc

ISO 8601 instant in UTC, to the second (UT1 before 1972). The site rounds these to the minute.

precision

sharp, apsis, flat or twin: how much the exact time means. See the methodology.

declination_deg

The Sun’s declination, for equinoxes, solstices and Echosuns.

distance_km

Earth to Sun, center to center, for perihelion and aphelion.

eot_s

Equation of time in seconds, positive when the sundial is ahead of the clock.

day_excess_s

Length of the solar day beyond 24 hours, noon to noon, for Longsol and Shortsol.

Using it

The data is free to use under CC BY 4.0: share it and build on it, commercially too, with credit to Solmanac. A credit can be as short as this:

Solmanac (2026). Earth and Sun moments, 1900 to 2100, computed from NASA JPL DE440. https://solmanac.app/data

The names Earlysun, Latesun, Evensun, Longsol, Shortsol, Echosun and Midreach are free for anyone to use. The underlying ephemeris, NASA JPL’s DE440, is free to use as well.