GRAND RAPIDS, Mich. (WOOD) — The unofficial start of summer is on the horizon with the latest sunsets of the year hitting Michigan in late June and early July. One viewer in West Michigan wants to know, what is the latest sunset in Michigan?

Due to the tilt of the earth, areas farther north in the northern hemisphere tend to have later sunsets in the summer than those farther south. In fact, along the Arctic Circle there are places the sun never sets — yielding 24 hours of daylight around the summer solstice. In general, the higher the latitude, the later the sunset near summer solstice.

Remember, sunset is a function of time zone. In general, people who live further west in their time zone will have later sunsets. Those who live close to the eastern edge of a time zone will have earlier sunsets compared to cities further west in their same time zone along the same latitude. For example, South Haven and Detroit are very similar in latitude, but because South Haven is farther west in the time zone, it boasts a later annual sunset.

Summer solstice will land at 10:57 a.m. on Wednesday, June 21 this year. The latest sunset of the year is a function of both latitude and how far west a location lands in its time zone.

The latest sunset time on Michigan’s mainland is Ontanagon, with the sun setting at 9:55 p.m. for almost two weeks in late June and the first few days of July. The latest sunset in Michigan ever? That goes to Isle Royal. The island is furthest north and quite west in the eastern time zone. The latest the sun sets on the island each year is 9:58 p.m., with nautical twilight clinging to almost midnight.