what does transit of planet means?

Answer 1

In general, the word transit describes any (apparent) passage of an object across a fixed line. For example, it could be a line formed by two lighthouses, with a ship seen 'in transit' by someone in one lighthourse.

It is also used for crossings in general (as in a 'transit' system that carries passengers across the city).

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Normally, in celestial mechanics, the word transit is used when the celestial object (planet, star, whatever) passes over the observer's meridian (longitude).

That is, when the object is directly south or north of the observer.

Transit marks the time when the object's altitude over the horizon is at its maximum (upper transit) or minimum (lower transit for circumpolar objects).

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In solar system astronomy, the word is used for inner planets (Mercury and Venus), describing the passage (or crossing) of the planet in front of the Sun. There was a transit of Venus (in front of the Sun) in June 2004 and there will be another one in 2012.

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In Astrology, the word is used in relation to planets: the manner in which their crossing of the 'horoscope' (i.e., a chart set up for a given person). In one particular use of the word (there are many), the transit calle 'planetary return' occurs when the planet returns to the position that it had at the time of the person's birth.

Astrologers like to pretend that this moment is important.

Answer 2

It means it passes in front of the Sun. Only Mercury and Venus can do that in our solar system, but planets orbiting other stars can pass in front of their Suns as seen from Earth too. It is kind of like an eclipse, but the planet is far to small to hide the whole Sun, so we call it a transit instead of an eclipse.

Answer 3

It means "to pass in front of" from our perspective.

Venus and Mercury can transit the sun (the other planets never pass in front of the sun from our perspective).

Satellites of the outer planets can transit their planets if their orbits are lined up with our point of view.

A transit is when a smaller-appearing object passes in front of a larger-appearing object.
If the object passing in front is larger, its called an eclipse or occultation (such as when the moon passes in front of a star).

Answer 4

When one crosses over another from our point of view. Most are best when the planet crosses over the disk of the sun.