Interactive 3D
Biology
Educational portal for Science, Biology, Chemistry and Physics.
Astronomy
Eclipse Simulator
See in real time how solar and lunar eclipses happen — with an interactive animation of the shadows, umbra and penumbra.
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Total Solar Eclipse
The Moon completely covers the solar disk. Visible only within the path of totality on the Earth’s surface.
Annular Solar Eclipse
Happens when the Moon is farther away and looks smaller than the Sun, forming a ring of fire around it.
Umbra and Penumbra
The umbra is the Moon’s full shadow — anyone inside it sees a total eclipse. The penumbra is the partial shadow, where the eclipse is partial.
Why isn’t there one every month?
The Moon’s orbit is tilted about 5° relative to the ecliptic. A perfect alignment only happens when the Moon crosses the plane of the Earth’s orbit.
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