Extreme Moon: The Major Lunar Standstill of 2024-2025

Summary

We observe the major lunar standstill by watching where the Moon rises on the eastern horizon and where it sets on the western horizon. In this way, the major lunar standstill is similar to observation of the Sun at the solstices. The solstices represent the most southern (winter) and most northern (summer) sunrise and sunset positions on the horizon. The Observatory has sunset lines inlaid on its lower West Terrace (as shown, at winter solstice). To the unaided eye, the position of sunset at the solstices does not seem to change for several days. Because the sunset seems to stand still, the time when this happens is called a solstice, which means “Sun still” in Latin. In one year, the Sun moves gradually from one extreme to another and then back again. These extreme positions for sunrise and sunset stay the same for thousands of years. People throughout history have observed the rising and setting Sun as a reliable way of calibrating the calendar.