Take warm clothing and springy boots

The Moon will go by in front of the Sun on Sunday September 13 –

partial solar eclipse of 2015 September 13
Half of an illustration in Astronomical Calendar 2015.

– but to see this partial eclipse you’ll have to be in southern Africa, southern Madagascar, or Antarctica.

Eclipse begins, though almost unnoticeably, when the edge of the Moon’s shadow first touches Earth, at a spot in the Kalahari desert where live the remnants of the indigenous people of the southern half of Africa, the Bushmen and Hottentots. (Did you ever see “The Gods Must Be Crazy”? I’m naive enough to think it one of the best movies ever.)

This is at 4:42 Universal Time, which by “summertime” clocks in Britain is 5:42 AM and in the eastern US 0:42, so farther west in America the date is still Saturday Sep. 12.

A little more than two hours later comes the middle of the eclipse. But the Moon and mostly-eclipsed Sun are right down on the horizon, as seen from a spot two thousand miles due south of Cape Town, in Antarctica, where it’s early spring but not, I think, warm.

Even if you get there and stand staring at your icy northern horizon, you still won’t be seeing quite the deepest partial eclipse. A slender arch of blazing Sun will show over the top of the black semicircle of the Moon, but it’s not as slender an arch as it could be. Why? Because to see it that way you’d have to jump 230 miles up into space. That’s the distance at which the axis or midline of the shadow whizzes past.

(It may look as if a jump from Antarctica will be a jump from which you’ll never return – but don’t worry, up is up, even in “down under.”)

Make that 230-mile jump and you’ll be in what’s called the “antumbra,” a cone of space beyond the tip of the Moon’s total shadow. From up there, you will see the silhouette Moon centered on the Sun, and around it that blazing ring complete.


2 thoughts on “Take warm clothing and springy boots”

  1. And, btw, I’m most certainly looking forward to the moon slipping into Earth’s shadow two weeks from now.

  2. PPpphhhht! I’ve travelled enough around the world mostly to catch total solar eclipses, some successful,, two NOT quite so :( ,, but to Antartica for a partial?? I think I’ll pass.. but I’m reminded of the movie “Eight Below”; a bunch of sled dogs left behind and their adventures, one including a great display of Aurora Australialis.

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