History ?

How old does something have to be to be classed as a historical artefact?
Obviously the moment a moment has gone it is history because that moment has passed.
This is a stone armillary sundial is at York Gate gardens ( where I did my shift this afternoon ).
Not usually seen from this view as l am stood at the entrance to meadow, mostly it is admired from the White Garden.
There is a bronze arrow going through the ball but it’s hard to see here.

The gardens were at one time private and created by a family from 1951 onwards and the sundial was added in 1968.

How history will reflect on current events in the world l just don’t know.
I was impressed and in agreement with Dan Jarvis MP and mayor for Sheffield City Region as he spoke so eloquently in Parliament today.