A solar eclipse
occurs when the Moon passes in front of the Sun, as seen from Earth. Oftentimes
the alignment is imperfect, resulting in a partial
solar eclipse. However, if the Moon completely covers the Sun from our
perspective, a total solar eclipse
ensues. And if the alignment is good, but the Moon is at a point in its orbit
where it’s too far from Earth to completely cover the Sun, an exposed ring of
sunlight surrounds the dark lunar disk. This third type of solar eclipse is
called an annular eclipse, from
“annulus,” Latin for “ring.”
On May 20, 2012, an
annular eclipse was visible from Asia to western North America, stretching
across the Pacific. Fortuitously, the path of annularity, a 200-mile-wide
swathe where the “ring of fire” was visible, crossed New Mexico and was
centered on Albuquerque. Although at this locale the eclipse began around 6:30
p.m. and was still in progress at sunset, most of it was observable. The
impending event created lots of buzz in the local amateur astronomy community,
not to mention among the general public and photographers at all skill levels.
Albuquerque became a destination for astronomy enthusiasts from across the
country.
World
map of the May 2012 solar eclipse
Line
of red circles = path of annularity
Figure
by Fred Espenak, NASA
My email inbox lit up
with discussions of eclipse-related timings, techniques, equipment, locations,
phenomena, and media misinformation. We fretted over how cloudy the western sky
had been lately. We verified the next annular eclipse visible in our area would
occur in 2023. We identified an upcoming (2017) total solar
eclipse visible from the U.S. (rare!) and evaluated both Kentucky and Wyoming
as prospective viewing destinations (Wyoming won).
My experience of the May
2012 annular eclipse, which I’ve recounted below, was a highlight of my
observing life thus far. And best of all, it came right to my doorstep. If
you’ve not seen one, I recommend you put it on your bucket list immediately!
*****
Eschewing
the designated public viewing site in Albuquerque where a crowd of 10,000 would
gather, we were seven strong at my astronomy club’s remote observing site. I
was joined by club members Jeff, Bill, and Carl, as well as two visiting
amateur astronomers from the Kansas City Club and one from Florida.
The
Kansas City folks were particularly thankful to be there. Arriving in
Albuquerque, they had tried contacting our astronomy club through its website
without success, somehow found (unpublished) coordinates for the observing site,
entered them into their GPS, and started driving.
They
got lost. They had no idea where they’d ended up: “in the middle of nowhere,”
as they put it. After a while, a young man came along in his car. They told him
they were trying to get to the astronomy club’s site. He led them through the
wilderness, deposited them at the gate, and vanished in a cloud of dust. Ah,
the kindness of mysterious strangers.
Like
an eating-contest contender training for gluttonous excess, I had methodically
prepared to cram as many experiences as I could into the hour-and-a-half-long
event. It was, after all, my first solar eclipse observation, and I wanted to
make it count. So I had with me four pieces of welder’s glass of varying
densities, 10x50 binoculars equipped with black polymer solar filters, an 80mm
refractor telescope equipped with glass solar filter and 25mm eyepiece, and a
piece of plywood drilled with several 7/64-inch holes—for making pinhole
projections during annularity, the fleeting Ring of Fire phase.
Welder’s glass and curious beetle
My
observing colleagues also came prepared for observing or imaging the event
safely, with properly filtered equipment. We scattered along the full length of
the observing field, extravagant in our use of the flat, graveled expanse and its
big-sky vista to the west.
Carl
set up to image with a Canon DSLR, shooting through our club’s vintage 6-inch
Astrophysics refractor. Brent from Florida was also imaging, with one DSLR
shooting through his refractor and a second piggybacked on his mount. The
Kansas City duo was observing with a 10-inch Dobsonian reflector telescope.
Jeff was packing eclipse glasses and a refractor. Bill busied himself with
fine-tuning the club’s new astrophotography equipment.
In
my haste to get to the site, I’d forgotten one critical piece of
equipment: a hat. The bright, hot,
cloudless afternoon boded well for eclipse visibility, but my deficit in
headwear quickly became uncomfortable. Fortunately I was able to borrow a ball cap.
DeAnna
and Leonard, a couple from the nearest town, arrived unexpectedly and parked their
big truck precisely between our equipment and the Sun. Oops. At our urging,
they hurriedly and abashedly moved their vehicle to a better spot. Although outfitted
with their own eclipse glasses, they were nevertheless curious to see what was
happening at our observing site.
And
then there were nine.
Eclipse watchers
Image
by DeAnna
I’d
brought an atomic clock from home so I could call out countdown times to each event
milestone—called “contacts.” Thirty seconds to 1st contact—the beginning of the
eclipse—I single-mindedly plastered my eye to my refractor, because it would
present the most magnified view.
Before
I actually saw the Moon’s silhouetted disk slide into view, I noticed that something was happening on the Sun’s outer
edge, a sort of subtle bubbling effect. Then the Moon took its first visible
nibble, accompanied by a sudden frenzy of drumming from the crowd of New Agers
who’d gathered at their ceremonial site half a mile away.
It
had begun.
First nibble by the Moon - lower right, at 4 o'clock position
Throughout
the eclipse, I was moving continually among my color and magnification
options—thrilled alike by the unmagnified lime green view through #12 welder’s
glass, the magnified-10-times deep orange view through the binoculars, and the magnified-16-times
yellow gold view through the refractor. Of course, we all shared views with one
another through our array of equipment, even taking turns looking through Jeff’s
vintage eclipse glasses, a souvenir from the 2001 total solar eclipse he’d
traveled to Africa to see. Together we witnessed the usually benign Moon
relentlessly devour each of three large sunspot groups on our freckle-faced
star.
At one point, Bill said, “Hey, turn around and look at our shadows.” We twirled in unison. Replacing our familiar shadows was a menacing band of gangly creatures with hideously misshapen heads and curiously deformed fingers, rendered otherworldly by the lunar cutout.
About
an hour into the eclipse, the Moon was almost entirely inside the Sun’s disk. At
2nd contact, it pulled away from the Sun’s limb (outer edge), and we had our
first exhilarating look at the Ring of Fire. I moved, mesmerized, from view to
view to view of that impossible ring suspended in the evening sky: blazing,
bodacious, biblical.
Image by DeAnna
Overhead, powder blue deepened to cornflower. DeAnna held her smart phone to the refractor eyepiece, snapped an image of the ring, and crowed, “Got it!” A nearby mockingbird took a deep breath and launched into a coloratura passage of trills, whistles, and high notes. At 30 seconds to mid-eclipse, I sprinted—with perforated plywood and camera—to the sunlit side of a white travel-trailer for my first-ever experiment with pinhole projection.
With the Sun behind me, I shoot my shadow and my board's shadow on a white background.
Rings of sunlight stream through the small holes, showing the Sun in mid-eclipse.
So easy, and so fun!
A
mere four minutes and nine seconds after 2nd contact, the
unstoppable Moon kissed the opposite limb of the Sun for 3rd
contact, the end of annularity. Planted at my refractor during both 2nd
and 3rd contacts, I observed dainty Baily’s beads, one of the items on my eclipse wish list. More
commonly seen during total solar eclipses, these are discrete beads of sunlight
briefly shining through the valleys and other irregularities along the Moon’s
outer edge, just before it pulls away from or connects with the Sun’s limb. Truly
exciting to witness!
The end of annularity: 3rd contact
After
the high drama of annularity, there was time for more leisurely pursuits. We
looked for and spotted Venus high above the eclipse, waiting in the wings for her star turn: a very rare and much
ballyhooed transit across the Sun in early June.
The
Moon continued to move eastward in its orbit, slowly unmasking the Sun. Clouds
drifted across the crescent Sun, flirting with the re-emerging sunspot groups.
Sunset approached, and the partially-eclipsed Sun descended into atmospheric
haze near the horizon. Needing less protective darkening as a result, I switched
to the #11 welder’s glass, and it was just right.
Moon leaving Sun’s disk, as clouds drift by
The
serrated western horizon began to gnaw on the abbreviated Sun. We knew we
wouldn’t see the end of the eclipse, 4th contact, when the Moon’s
disk completely leaves the Sun, because sunset would occur first.
As
I drank in another long, satisfying look through the telescope, a fissure
suddenly opened on the Sun’s surface. What the ???! Realization dawned. “Jet
trail on the Sun! Shoot! Shoot!” I yelled, and the imagers began clicking
furiously. Big orange jack-o’-lantern grin. Shark fin. Glowing ember. Gone baby
gone, ushered out with another flurry of drumbeats.
Partially eclipsed Sun with jet trail
Shark fin: the still-eclipsed Sun sets
Do
it again. Oh, do it again. Please? Finally I understand the compulsion, the addiction,
the fever that grips eclipse chasers. Must. Find. The. Antidote. I hear it’s in
Wyoming.
