Did you see that big moon last night? August is the time of the Full Sturgeon Moon, named for the best time to catch sturgeon in the Great Lakes. Because the moment of lunar fullness occurred this morning at 4:26 a.m., we get a full moon “spillover effect” or two nights in a row of what essentially is a full moon. Last night’s moon was missing the narrowest of slivers along its left or eastern side. Tonight, a sliver will be absent from the west side. I doubt you’ll be able to see this clearly with the naked eye but binoculars or a telescope will show it.
Last night, the moon rose a short time before sunset for the Americas because it was not quite 180° opposite the sun in the sky. Tonight it rises just a bit after sunset because the moon is a titch past full and closer to the rising morning sun than the setting evening sun. When moonrise occurs before sunset, the rising moon looks very pale in a sky still flush with daylight, but when it occurs after sunset, the sky has begun to grow dark, and the effect of its rising is more dramatic. I encourage to see such a moonrise tonight (Aug. 18) and even tomorrow night. To find the time the moon rises for your location to plan an evening of moongazing, click here.
With the sun now sliding southward, reflected in its earlier setting and later rising times this month, the moon is moving northward. You’ll notice how much higher the full moon appears compared to the time of the summer solstice if you stay up late tonight. As the moon approaches its highest point in the sky due south around 1 a.m., its rays are more direct and your shadow shorter. Nighttime shadows will grow shorter each month until they’re at their most compressed at the December full moon, when our satellite will be standing in the same spot the sun was back on the first day of summer in June. And so the painted ponies go up and down.