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Norman Sperling
(c) 2002 Norman Sperling. Excerpted with
permission from "What Your Astronomy Textbook Won't Tell
You" (ISBN 0-913399-04-3).
Everyone who sees a total solar eclipse remembers
it forever. It overwhelms the senses … and the soul
as well – the curdling doom of the onrushing umbra,
the otherworldly pink prominences, the ethereal pearly corona.
And, incredibly soon, totality terminates.
Then it hits you: “That was supposed
to last a few minutes – but that couldn’t have
been true. It only seemed to last 8 seconds!”
This effect frustrated my first 4 eclipses,
and most fellow eclipse fanatics assure me they’ve been
bothered by it, too. Yet tape recordings, videos, and the
whole edifice of celestial mechanics all claim that it did
last the full, advertised 2 to 7 minutes – to within
a few seconds, that’s what really happened.
Where did all that precious time get lost?
Eclipse Watching
True eclipse freaks recognize only 2 modes
of life: eclipse expeditions, and preparing for them. They’ll
devote a year or 2 to perfecting equipment: telescope, camera,
weird filters and film; sandproofed, soundproofed, rainproofed
(heaven forbid!), and bug resistant. No matter what their
expedition sees or does along the way, they’ll fret
about totality. Will the clouds part? Will * the * equipment
* work? WILL * WE * SEE * IT?
The partial eclipse is a tantalizing, exasperating
hour and a half. Then the diamond ring forms, gleams and vanishes
– and at last they have totality. They gape in awe for
just a second, then dive desperately into the sequence, many
times rehearsed, of exposures, adjustments, notations so hurried
they can only be unraveled from the tape recordings afterwards.
Inevitably, totality terminates too soon,
often even before the planned sequence does, and they never
make it to their own hard-won free-looking phase. “But
I got it on film!” they proclaim, “And I can frame
that and glow at it forever – even though … I
only saw it … through the … camera’s finder.”
The novice and the non-astrophotographer
take the hang-loose approach. Restless in the partial phase,
they get impatient and even quarrelsome around the 1-hour
mark. But in the last 10 minutes they can feel it: totality’s
a-comin’. The world is darker, oranger; shadows look
oddly sharp-edged. There’s a nip in the air, the birds
are atwitter, and shadow bands go skittering around. The ominous
umbra sweeps in, the corona unfolds, the diamond glitters
and is extinguished, and “OH * MY * GOD * THAT’S
* THE * MOST * BEAUTIFUL * THING * I’VE * EVER * SEEN!”
They stare transfixed, all their senses open, trying to take
in as much as they can.
Unwilling to concede that totality can’t
linger past third contact, they keep staring at the emerging
solar sliver long after it gets painfully bright. Finally,
they must be ordered to look away. Then, limp, with self-satisfied
grins, they applaud, or yelp, or shuffle aimlessly and ask
where the next one’s gonna be and how to get there.
Both styles of eclipse-watching yield the
viewer a solid 8 seconds of memory. I replayed all my mental
images of my first 4 totalities in about half a minute. And
that was after seeing 12½ minutes of totalities. The
other 12 minutes just weren’t there! Poof!
Transfixed
The culprit is attention span. If you stare
transfixed, your mind, knowing the scene isn’t changing,
says “I already know that,” and refuses to store
away the same image yet again.
So the solution is not to stare.
What? Not look at that most marvelous miracle
you’ve traveled umpteen thousand kilometers to see?
No, I didn’t say not to look, I said
not to stare.
Pre-record a cassette, timed to start at
the first diamond ring. On it, tell yourself what to notice
during different parts of your precious few minutes in the
Moon’s shadow. Notice how the umbra envelopes you, enjoy
the diamond ring, then examine the prominences (they’re
bright, so you don’t have to be fully dark-adapted).
Next, survey the corona – its general shape, and any
outstanding features.
Switch away for a few seconds, to check the
colors all 360° around the horizon. Since totality is
just starting, it’ll be darkest in the west, lighter
in the east. Now back to the Sun. Your eyes, now partly dark-adapted,
are ready for the corona. Which is the very longest streamer,
and how far out can you trace it? Where is the innermost dark
wedge? Pick out an interesting pattern of filaments and make
a mental engraving of it.
OK, back to the horizon. Sweep around again,
and notice how much difference a minute or 2 makes. The west
is lightening, foretelling totality’s end, and the east
is dark, where folks down-path are just now getting theirs.
Finally, back to the Sun. Review the best
coronal details. Look again at prominences, since there’s
a whole different crop of them on the third-contact side.
Watch for the pink fringe of chromosphere that anticipates
– yes, here it comes – the second diamond ring.
How quickly the corona fades! – and
now, even the last of it is going – and it’s incredible
how bright even that tiny wedge of Sun’s surface can
be!
And now this eclipse, too, is over. But this
time you’ve won. From each separate span of attention
during totality you can savor your 8 seconds of mental replay.
If you moved your attention enough times, you’ll recall
many times that 8-second limit. Yes, Sperling’s 8-Second
Law can be beaten!
Norm Sperling is editor of The
Journal of Irreproducible Results. Previously he was
assistant editor of Sky & Telescope magazine
and Science Editor at AltaVista.com. Norm teaches astronomy
in universities around San Francisco, wrote the new book "What
Your Astronomy Textbook Won't Tell You," and co-designed
Edmund Scientific's Astroscan telescope. 
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