Gamma (eclipse)

Gamma of a central total eclipse. This illustrates solar eclipse gamma: The red line shows the least distance from the center of the Earth, in this case approximately 75% of radius of the Earth. Because the umbra passes north of the Earth's center, gamma in this example is +0.75.

Gamma (denoted as γ) of an eclipse describes how centrally the shadow of the Moon or Earth strikes the other body. This distance, measured at the moment when the axis of the shadow cone passes closest to the center of the Earth or Moon, is stated as a fraction of the equatorial radius of the earth (6378.137 km).^[1]

^ "Key to catalog of solar eclipses". NASA Eclipse Website. NASA., "Key to catalog of lunar eclipses". NASA Eclipse Website. NASA.

[1] "Key to catalog of solar eclipses". NASA Eclipse Website. NASA., "Key to catalog of lunar eclipses". NASA Eclipse Website. NASA.

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