Astronomical summer can vary by almost two days each year (June 20, 21, or 22). Trying to compare a heatwave that started on June 18 one year versus June 22 the next is a nightmare for data scientists.
Is it when the calendar flips to June? Or is it the moment the Earth reaches a specific tilt in its orbit?
We all know the feeling: the pool opens, the grill is fired up, and the sun doesn’t set until after dinner. But if you ask ten different people when summer officially starts, you’ll likely get two different answers.
