Understand the difference between solstice and equinox in 2025, explained simply for students. Learn how Earth’s tilt affects ...

Friday is the longest day of the year north of the equator, where the solstice marks the start of astronomical summer.

When are 2025 solstices and equinoxes? Spring equinox: March 20, 5:01 a.m. ET Sun is overhead at the equator Summer solstice: June 20, 10:42 p.m. ET Sun is overhead at Tropic of Cancer ...

Here's what to know about the upcoming 2025 summer solstice this week and when it last fell on June 22 — the rarest date for the longest day.