Calculation of the position

This feature allows you to view at any time (between 1951 and 2024 - specify here the validity of the calculation) the image of the Sun during its transit on the great meridian line of the Paris Observatory (02° 20 '14 "E - 48° 50' 11" N). This synthetic image is one that would be obtained if the gnomon was composed of a simple opening, not its current lens. A low resolution version of the line and the pavement of the Cassini room is also available.

Click and drag to the right or left to move along the meridian line.

Date :
Time of passage on the meridian:
Elevation of the sun:
Position of the ellipse:
Major axis of the ellipse:
Small axis of the ellipse:
Apparent diameter of the sun: