And we are still approaching major lunar standstill. Right now, the declination of the full moon is -27 degrees, so it's almost as far south as it can get.
In addition to the April 8 total solar eclipse and vibrant displays of auroras, there's another celestial treat for skywatchers this year: the first "major lunar standstill" since 2006. During this event, the moon rises and sets at its most extreme northerly and southerly positions on the horizon, reaching its highest and lowest points in the 18.6-year lunar cycle.
This is possible because the moon doesn't follow the same path as the sun. Its rising and setting positions on the horizon change constantly due to the movements of Earth and the moon. The solar system is flat, with the planets orbiting the sun on the same plane, known as the ecliptic. Earth rotates on an axis tilted by 23.4 degrees with respect to this ecliptic, causing the sun to rise and set within almost 47 degrees — a range it gradually covers over an entire year. The moon's orbit is tilted by 5.1 degrees relative to the ecliptic, allowing it to rise and set within a 57-degree range in any given month.
This explains why the moon can sometimes rise and set at points on the horizon farther north and south than the sun can.
A major lunar standstill, or lunistice, occurs when the tilts of both Earth and the moon are at their maximum. During this period, the moon rises and sets at the extremes of its range. It rises at its very highest northeasterly point and sets at its very highest northwesterly point. During this period, it also rises at its most southeasterly point and sets at its most southwesterly point.
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