Overview
- The solstice, which occurs at 08:24 UTC (4:24 a.m. ET) on Sunday, June 21, is a single, exact astronomical instant when the Sun reaches its northernmost declination.
- Earth’s roughly 23.5° axial tilt causes the event and it marks the official start of astronomical summer in the Northern Hemisphere.
- Daylight effects vary sharply by latitude with parts of Alaska and northern Canada seeing near‑continuous daylight and many mid‑latitude cities getting roughly 15 to 16 hours of sun.
- Thousands are expected at Stonehenge for sunrise observances as English Heritage is allowing open access and will livestream the moment while local parking is sold out and public transport is advised.
- The solstice brings the most daylight but not the year's peak heat because of seasonal lag, and the earliest sunrise and latest sunset do not fall exactly on the solstice due to orbital and solar‑time effects.