Lunar Eclipse Geometry
This interactive simulator explores Lunar Eclipse Geometry in Astronomy & The Sky. Sun–Earth–Moon: Earth’s shadow on the Moon; total, partial, and penumbral (schematic colors). Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.
Who it's for: Best once you already know the basic definitions and want to build intuition. Typical context: Astronomy & The Sky.
Key terms
- lunar
- eclipse
- geometry
- lunar eclipse geometry
- astronomy
How it works
A lunar eclipse happens at full Moon when the Moon enters Earth’s shadow. The umbra is where the Sun is completely hidden by Earth; the penumbra receives only part of the sunlight. The Moon’s orbit is tilted, so not every full Moon is eclipsed.
Key equations
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Axial Precession
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Ecliptic & Zodiac Band
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Hertzsprung–Russell Diagram
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