Harvest Moon 2021: When and how to see September's full moon


Oct 22, 2019
Last night I did some de Luna, Jupiter, and Saturn observing using my telescope. Not Full Moon but getting close and very bright Moon :)

Observed 2130-2230 EDT/0130-0230 UT. Full Moon 20-Sep-2021 2354/2355 UT. Bright, waxing gibbous Moon tonight. I viewed using 90-mm refractor, 14-mm eyepiece, and 1.8x Barlow lens for 129x views. True FOV ~ 33.6 arcminute. The Moon's angular size tonight ~ 31.45 arcminute according to Virtual Moon Atlas. I used Starry Night Pro Plus 8, and Stellarium 0.21.1. I also used #12 Yellow filter throughout observations. Aristarchus crater distinct on the Moon, Tycho crater, Copernicus, Archimedes, Aristillus, Autolycus, and many others visible along the terminator line. The waxing gibbous Moon was bright, even using the #12 Yellow filter. Saturn was lovely view along with Titan moon distinct. Cassini division visible, some cloud bands on Saturn, and small slice of Saturn's shadow on the rings distinct. At Jupiter, many cloud bands visible, 3 Galilean moons on one side (Io, Europa, Ganymede), one Galilean moon (Callisto) on the other side. The star 45 Cap < 10 arcminute angular separation from Jupiter's position tonight, looked almost like another moon :). Stellarium 0.21.1 reports the apparent magnitude +5.95, and spectral type A7 IV/V, a bit more than 176 light years distance with stellar parallax of 18.52 mas. Jupiter about 4.142 au while I viewed with a good angular size near 48 arcsecond. At 129x, the telescope view resolved to about 2.3 arcsecond so plenty of detail visible at Jupiter and Saturn, as well as the Moon. The Moon transit my location at 2345 EDT/0345 UT. Jupiter transit at 2300 EDT/0300 UT, and Saturn transit at 2154 EDT/0154 UT. Jupiter and Saturn retrograde in Capricornus. The Moon in Aquarius and does not retrograde :)