Essen, horizontal view

Internet Project

Observing, Photographing and Evaluating the

Transit of Venus, June 8th, 2004

Essen, equatorial view

Project 1: Measuring the Radius of Venus' Orbit - First Results

Impressions from Essen

directing Venus along a stick

pair of compasses,
especially constructed for these measurements

Pins show the relative directions to Sun and Venus.

Results from Essen

Date Method Results
 December 21th, 2002 (La Palma)   directing Venus along sticks, projecting the Sun  45.5o
December 26th, 2002 (La Palma)   46.5o
January 3rd, 2003 directing Sun and Venus above pins 46o
January 10th, 2003 sextant  46o53'.2 
  directing with a special pair of compasses 47o
January 17th, 2003 sextant 46o45'
January 31th, 2003 directing Venus and Sun along sticks 46o
February 11th, 2003 directing Venus and Sun above pins 44o

The method of La Palma is described in an additional document. The other methods may be imagined with the help of the above pictures.

Results due to Gymnasium Fürstenwalde


On February 20th we've sent around a mail;

" We have now determined the radius of Venus' orbit by own measurements! It is quite exactly:"

or, in other terms,

back to the main page

Prof. Dr. Udo Backhaus
last modification:  March, 28th 2008