Venus and Saturn are still quite close as September begins, and will be seen high in the eastern sky at the beginning of twilight all month long. Mercury makes a good, albeit brief, appearance also in the pre-dawn sky, and it teams up with Regulus when it is at its best. The moon does its part, and could get our attention a few times.

Sept. 1: Saturn is just the width of your finger (with your arm straight out) above and left of sparkling Venus. Look for them high in the east about 5:15 a.m. (All times are given for the Lewiston-Auburn area.)

Sept. 9: A crescent moon will be approaching Saturn this morning, and we will find it as high above that planet as Saturn is above Venus. They can be seen well up in the east about 5:30 a.m.

Lower down and left of east at that same time, Mercury and Regulus, the brightest star of Leo, will be quite near each other. Mercury will easily outshine Regulus, which will be less than half a finger to the lower left.

Sept. 10: Mercury and Regulus will be even closer together this morning, with the star just to the upper right of the brighter planet. They should be visible low and a bit left of east, as late as 5:30 a.m. in a clear sky. Since they will be so very close, binoculars might be useful for seeing them separately. A nifty crescent moon will shine less than a hand above and left of brilliant Venus.

Sept. 16: We have an opportunity to see a very slender crescent moon just above Spica at dusk. They will be low and left of west, and 7:20 p.m. will be the best time to try for them. Binoculars might be handy for this.

Sept. 21: Today’s first-quarter moon will be the most southerly of the month. When the moon is at this phase, it follows roughly the same path in the sky as the sun does three months later. Thus this moon will be like the winter sun.

Sept. 22: The sun will be exactly midway between its extremes as our fall equinox occurs at 12:30 p.m. The sun will rise due east, set directly west and give us 12 hours of daylight. We can start looking for the leaves to give up the ghost.

Sept. 28: The moon will be full this evening, and being the full moon nearest the equinox makes it our harvest moon. For five days centered on the 28th, the rising time of the moon will change by only 20 minutes from one evening to the next. Thus, we have bright moonlight to light up the crops before all the sunlight is gone.

The planets cavort in the morning sky, and another turn of the seasons comes our way. If you feel like boasting a bit early in the month, go right ahead, because pride always goes before the fall.

Roger Ptak is professor emeritus of physics and astronomy at Bowling Green State University in Ohio and author of the popular astronomy book “Sky Stories.” He and his wife now live in Northport. His e-mail address is dptak//fermi.bgsu.edu/~ptak/star/star.html.