Students section

Welcome to the "Calendars, mirrors of the sky and cultures" website!
Multimedia animations below will help you better understand astronomical phenomena such as seasons, phases of the moon ... You even see, through the history of calendars, that astronomy is present in our everyday life.
(French versions)

Sun path through the sky

This animation shows the apparent motion of the Sun in the sky. You can change the season and see if the sun path changes, or if it rises and sets in the same place.



This animation shows the motion of the Earth around the Sun. You can zoom in and out, change the date or the angle of view.
Does the day have always the same duration?


Common and leap years


In this animation, you can see the motion of the Earth around the Sun. Each year, there is a small shift: the Earth does not come back exactly the same place.
What will happen in four years?


Phases of the Moon

Scroll days and observe the appearance of the Moon. How long does a full cycle last? Why do we see the moon differently?

The 3 cycles: day, month, year

What are days, month, and years? How are these periods linked with the motions of the Earth, the Moon, and the Sun?

The history of calendars

This animation tells you the history of our calendar, called the Gregorian calendar.
Who was Gregory? Why did he reform the calendar of Julius Caesar? Why is our calendar based on the Sun, while Muslim’s one, for example, is based on the Moon?

(Note: this animation weighs more than 3 MB, it may take a little time to load)


Project partners

La main à la pâte Foundation ESA