BETHLEHEM, Pa. — Brad Klein reviews upcoming astronomical highlights with Bethlehem’s ‘Backyard Astronomy Guy,’ Marty McGuire.
This week, they look forward to the arrival of ‘astronomical spring’ on the morning of March 20.
Meteorological spring comprises the months of March, April, and May. But an astronomical definition can be much more precise.

“Thursday, March 20, at 5:02 a.m. is the actual time of the spring equinox,” McGuire said.
There are a number of ways to define the equinox, but perhaps the easiest to imagine is: the equinox occurs at the moment that the sun appears directly over the equator, neither to the north or south. And that moment, in the early hours of Thursday, is the spring equinox here in the Northern Hemisphere.
It’s the autumnal equinox for those living south of the equator.
