


20042012: the transits of Venus

Calculating the EarthSun distance
The observation of the transit of Venus provides the
opportunity to recalculate the distance EarthSun known as "astronomical
unit". Several methods are available at several levels of difficulty.

understanding the principle of the calculation
The first step is to understand the principle of the calculation.This principle
is explained in the
information
sheets n°04a, 04b and 04c. From these sheets, it
is possible to build an algorithm of calculation. This is not simple and
it will be easier to use the information sheet n°05a providing a simplified method
with examples. The building of an algorithm is then possible.
The information
sheet n°05b
provides some formulae easy to use in order to be able to calculate
the astronomical unit from two observations made from two sites.

calculating yourself the EarthSun distance
We propose to two observers located on two different sites
to calculate themselves the astronomical unit using their own
observations. The information sheet n°05a and the formulae of
the information
sheet n°05b to be followed line by line
allows it. The search for far correspondants may be made through
our correspondant page.
Attention, the sites of observation should be chosen
carefully as it is explained in the
information sheet n°06.

