Tonight, on the night of October 22-23, the moon swings to the northernmost point in its monthly orbit around Earth. In the U.S., the moon is farthest north for the month on October 23, at 5:13 a.m. EDT, 4:13 a.m. CDT, 3:13 a.m. MDT or 2:13 a.m. PDT. Tonight’s moon shines in the vicinity of Elnath, the constellation Taurus’ second brightest star, after Aldebaran. As seen from mid-northern latitudes, the waning gibbous moon and Elnath rise into the east-northwest sky around 9:00 to 10:00 p.m. local time. At latitudes south of the equator, the moon and Elnath rise at late evening or around midnight.
The much brighter star to the upper left of the moon and Elnath this evening is Capella, the northernmost first-magnitude star in all the heavens. This beacon star lights up the constellation Auriga the Charioteer.
The moon reaches its farthest point north of the celestial equator once a month. In contrast, the sun reaches its northernmost point but once a year. The sun’s farthest point north is frequently called the June (or northern) solstice. The moon’s northernmost point is sometimes referred to as a northern lunistice or a northern standstill.
After the moon and Elnath rise tonight, they’ll climb highest up in the sky at roughly 4:30 a.m. local daylight saving time (3:30 a.m. standard time). For the Northern Hemisphere, the moon won’t soar quite as high up as the summer solstice sun. And in the Southern Hemisphere, tonight’s moon won’t descend quite as low as the winter solstice sun. That’s because the moon only swings from about 19.5o south (October 9) to 19.5o north (October 23) of the celestial equator in October 2013. In contrast, the sun swings from about 23.5o north of the celestial equator on the June solstice and 23.5o south of the celestial equator on the December solstice.
Learn the star Elnath for handy reference. Whenever you see the moon close to this star, you’ll know that it’s the time of the month when the moon is at or near the northernmost point in its orbit!