¡SkyCaramba! Weekly astronomy blog for the week of October 11 to 17, 2015
Over the next month or so, look at the moon whenever it’s up, especially whenever it’s rising or setting. Notice how far north or south it goes in the sky. In about a month’s time, it goes from its northermost point, across the equator, to its southernmost point, across the equator, and back to its northermost point again.
Last month, the moon reached 18.1° from the equator at its northernmost and southernmost points. This month, it’s getting a little farther at 18.2°. It will be 18.3° south on November 15 and 18.4° north on November 27. Those measurements will keep increasing month after month until February and March 2025 when the moon reaches 28.7° from the equator. Then, the moon’s reach north and south shrinks just a little each month until after another nine years it’s down to 18.1° again.
Even though the moon isn’t really holding still during any of these motions, the extremes in this 18.6 year cycle have come to be called lunar standstills. The part of the cycle the moon just went through is called a minor lunar standstill. Likewise, the part the ...