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Glossary

With Local Prediction of the Lunar Eclipse, you can find local predictions of the phenomena.

Lunar Eclipse

Mechanism

The Moon reflects the light of the Sun and shines. Lunar Eclipse occurs when the Moon passes through the shadow of the Earth so that the light cannot reach the Moon (Figure). Lunar Eclipse can be Penumbral when the Moon is in penumbra, Partial or Umbral when the Moon is in umbra, and Total when the whole Moon is in umbra. Lunar eclipse is visible where the Moon is visible.

With Local Prediction of the Lunar Eclipse, you can find predictions of eclipses.

Types

Penumbral	Partial (Umbral)	Total

Eclipse Maps

Lunar eclipse progresses in the same way wherever the Moon is visible. So you can judge the visibility with moonrise and moonset times. Eclipse Map shows the area using moonrise and moonset lines.

"Visible" shows the area where whole eclipse is visible. Every time you cross the line, the Moon is under the horizon at time of certain phenomena and not visible.

Glossary

• Position Angles (P.A.)
  • p : Direction of the center of Umbra with respect to the center of Moon, measured counterclockwise from celestial north
  • q : Direction of zenith with respect to the center of Moon, measured counterclockwise from celestial north
  • V : Direction of the center of Umbra with respect to the center of Moon, measured counterclockwise from zenith, i.e. V = p - q.
• Other terms
  • S.D. : Semi Diameter
  • Dist. (d) : Angular distance between the centers of Umbra and Moon
  • Mag. (D) : Percentage of diameter of Moon covered by Umbra. D = (Semi Diameter of Umbra + Semi Diameter of Moon - d)/(2 * Semi Diameter of Moon)