Some folks who traveled four hours or four days to experience totatlity during the recent solar eclipse were disappointed when their viewing experience was disrupted by cloud cover. But some of those eclipse chasers saw something those under clear skies didn’t get to see. As totality approached, the shadow of the moon raced along the clouds at 1000 miles per hour, swallowing air and land and sea. Pretty amazing, for a cloud-obscured celestial event. And for more info on lunar shadows, here’s a great lowdown from Astronomy Now:
Increasingly taking charge of the evening sky, [the moon] becomes more obvious against a darkening backdrop as its phase advances towards first quarter. Afterwards circling further behind our planet, it makes its appearance ever later into the night as sunlight steadily consumes the Earth-facing surface until the maximum illumination of full Moon.
In the 14 or so days between new and full, the shadowed line between light and dark that we call the terminator passes through some of the Moon’smost fascinating features – some well-trammelled, others less so. I would like to take you on that journey, sampling just a few of those treats, looking through three visual windows: with the eye alone, through binoculars (by which I mean the ‘classical’ 7× to 10 × 50mm class) and with the aid of a small telescope of maybe 70- 80mm (~three-inch) aperture.