An equinox is a twice-yearly event in March and September when the Sun is directly above the equator, causing nearly equal day and night across the globe. This year's autumn equinox will take place ...

The Earth became darker from 2001 to 2024, meaning it reflects less sunlight, a research team reports in the journal Proceedings of the National Academy of Sciences. The development is more pronounced ...

Day and night will get equal time for a brief moment Monday as much of the world heads into fall. The autumnal equinox arrives Monday, marking the start of the fall season for the Northern Hemisphere ...

The autumn equinox is now upon us! Today marks the moment that the sun crosses the celestial equator, ushering in the beginning of astronomical autumn in the northern hemisphere, which brings with it ...