Measurement

Eclipses and Sky Events

The GeoLira global eclipse calendar uses the NASA GSFC catalog and the work of Fred Espenak. It shows upcoming events, their type and the instant of greatest eclipse in TD. Local visibility is not guessed here: it requires a separate calculation for the observing location.

Foundation

The GeoLira global eclipse calendar uses the NASA GSFC catalog and the work of Fred Espenak. It shows upcoming events, their type and the instant of greatest eclipse in TD. Local visibility is not guessed here: it requires a separate calculation for the observing location.

An eclipse requires special geometry, not only new or full moon

The Moon's orbit is inclined by about 5 degrees to Earth's orbital plane, so most new and full moons pass above or below the exact alignment required for an eclipse. An eclipse occurs when the appropriate phase is also sufficiently close to an orbital node. The NASA catalog distinguishes partial, annular, total and hybrid solar eclipses, and penumbral, partial and total lunar eclipses.

Event visibility is local

The fact that an eclipse occurs astronomically does not mean it is visible from every location. For solar eclipses the paths of the penumbra, umbra and antumbra matter, while for lunar eclipses the Moon must also be above the local horizon. GeoLira separates the global instant of greatest eclipse from a local observing window and does not claim local visibility without a separate observer-location calculation.

Precise ephemeris does not imply biological effect

NASA publishes the instant of greatest eclipse in a dynamical time scale labeled TD in the eclipse catalogs. It is not local civil time. Precise ephemerides and predictable geometry are not evidence of a medical, psychological or personal effect. Astronomical data and symbolic interpretation remain separate product layers.