A Sundial showing Solstice

If the day and time are right, this peculiar sundial will tell you: SOLSTICEImage credit Jean-Marc Mari

Only then will our Sun be located just right for sunlight to stream through openings and spell out the term for the longest and shortest days of the year. But this will happen today (and again in December).

The sundial was constructed by Jean Salins in 1980 and is situated at the Ecole Supérieure des Mines de Paris in Valbonne Sophia Antipolis of south-eastern France.

source APOD