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Glossary

With Local Prediction of Transit of Planet, you can find local predictions of the phenomena.

Transit of Mercury, Venus

Mechanism

Since Mercury and Venus are inside the orbit of the Earth, the line Sun - Mercury or Venus - Earth can become straight. This is called Transit of Mercury or Venus and the planet, looks like tiny black point, passes in front of the disk of the Sun. If the disk of the planet is as large as the disk of Moon, it is called Solar Eclipse. Caution! When you observe transit of planet, you MUST NOT directly look at the sun. Otherwise, you might loose your eyesight.

• Local Prediction of Transit of Planet
• Major phenomena in 2012(Japanese Only)
• Transit of Mercury(Japanese Only)
• Transit of Venus(Japanese Only)

Transit Maps

Transit Map gives you hints where the transit is visible.

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

Glossary

• Position Angles (P.A.)
  • p : Direction of the center of planet with respect to the center of Sun, measured counterclockwise from celestial north
  • q : Direction of zenith with respect to the center of Sun, measured counterclockwise from celestial north
  • V : Direction of the center of planet with respect to the center of Sun, measured counterclockwise from zenith, i.e. V = p - q.
• Other terms
  • S.D. : Semi Diameter
  • Dist. (d) : Angular distance between the centers of Sun and planet