NASA highlights the science and history of the equinox

NASA is drawing attention to the equinox as both a seasonal marker and one of humanity’s oldest astronomical reference points.

The agency notes that the meaning of an equinox can feel different depending on location, bringing longer nights and cooler conditions in some places while signaling more daylight and milder weather in others.

Observing and predicting equinoxes formed part of early astronomical practice, and many ancient observatories tracked them alongside the more visually pronounced solstices. NASA’s item presents the event as a reminder of the long relationship between seasonal observation and astronomy.