In 2024, June 20 marks the summer solstice, the first official day of astronomical summer. “Solstice” means the sun has gotten as high in the sky as it’s going to get for the year; on Thursday, that will happen at 4:51 p.m. Eastern Daylight Time. [time-brightcove not-tgx=”true”] For those looking to pass the time during those extra hours of natural sunlight for reading, below TIME rounds up some surprising facts about the summer solstice and its history. The summer solstice is the longest day of the year In New York City, for example, the sun will rise on Thursday at 5:24 a.m.