The transit of Mercury on 2003 May 7



 Next Tansit on 2117 December 11/12

Time to go by:


There are periodic astronomical events that could never be observed by any human alive today. One of these is the transit of Venus on June 8, 2004.

On this day half our globe will be able to watch the tiny black dot of the planet Venus moving across the disc of the sun. Given a cloudless sky, all you'll need is a sun filter to follow the spectacle for several hours by your naked eyes (check your eyes).

The previous transit of Venus occurred on December 6, 1882 -
one of merely five events of its kind ever watched by mankind.


Which conditions have to be fulfilled for a Venus passage ?
Why have Venus transits been of great importance for astronomy ?
 Which other planets can show a transit ?

When and how often does a Venus transit happen ?

Applet: Transit Motion

Applet: Planetary Motion

Applet: Phases of Mercury and Venus

  Applet: Venus Transit Observer


History and Astronomy

Conjunctions and Transits

online computing by JavaScript

The Period of Transits

within 234 years 4 transits occur


the Transits is invisible in Europe


the predictions

Jeremiah Horrox

first witness of a transit of Venus in 1639

Edmond Halley

A new Method of determining the Parallax of the Sun

1761 June 6

astronomers observe the transit at 120 locationso

1769 June 3
Captain Cook

the expeditions
observer of the transits of 1769


the transit of 1874, December 9


Photo of the 1882 transit of Venus

2004, June 8

Details of the transit

2004, June 8

Calculating the parallax


the solar parallay by Venus transits and by modern methods

Arno Schmidt

about the European expeditions in 1769

Thomas Pynchon

"Mason & Dixon" observe the transit of 1761

2004 June 8

the transit of Venus will be visible from Europe, Africa, Asia, and eastern parts of America


web links and books


Planetary Motion and Phases of Mercury and Venus

Please visit my
GeoAstro Applet Collection