Monkey-Bar Moon Swings From Jupiter To Saturn This Week

The waxing crescent swings from Jupiter to Saturn in the coming nights. It’s Jupiter’s turn tonight. Stellarium

My older daughter used to love to swing from the monkey bars at our local playground. She’d lean forward and lunge toward the nearest bar, grab it and use the momentum of her body to swing forward and grab the next bar. And the next and the next until she’d gleefully arrive at the other side.

Jupiter and Saturn are like those rungs on the monkey bars. Tonight the waxing crescent moon will grab hold of Jupiter, dangle for the night and then swing over to Saturn on Saturday and hang there, too. These close approaches of the moon to a planet are called conjunctions. During both conjunctions the moon will stand about 2° or four lunar diameters from each planet at dusk.

Use these simulated views to help you find Jupiter in the daytime sky. Stellarium with additions by the author

Tonight just look toward the southwest (sunset direction) at dusk and find the moon. Jupiter will shine just to its lower right. As the sky darkens they’ll look even prettier. Don’t go out too late though! The duo sinks into the west after about 9 o’clock. On Saturday (Oct. 5) the first quarter moon will hang to the lower left of the planet Saturn. Since Saturn is further east of the sun than Jupiter it sets more than an hour later.

Once again the moon’s proximity to Jupiter means we’ll have the opportunity to spot the planet in the daytime sky with binoculars. Earlier in the day the two will be only ¾° apart or just 1.5 moon diameters. That happens around 3 p.m. Central Time (4 p.m. Eastern; 2 p.m. Mountain and 1 p.m. Pacific). If you have a clear blue sky look for the moon low in the southeast. It will stand about 15°-20° (almost two fists) high for the central U.S. at that time. Aim the binoculars at it and carefully focus. Jupiter will be in the same field of view below and to the right of the moon. The planet will look like a tiny, pale white dot against the blue. Can you see it so early in the afternoon?

This is a “wild” photo unrelated to the text, but I wanted to share it. It is a remarkable cloud formation shaped like an enormous raft that floated over Lake Superior about a week ago. I was out photographing lighting over the lake in Duluth at the time. We sometimes think of clouds getting in the way of stars, but they can be equally beautiful. Time exposures capture a sense of motion. Bob King

It will easier to see once the moon reaches its peak altitude around 5:30 p.m. local time. Look due south to find the moon then corral it in binoculars. Jupiter will now be a little more than 1° (two moon diameters) to the lower right of the moon. If your binoculars magnify 7x or higher the planet will appear like a tiny disk, not a point like a star.