The Annular Eclipse of 2012

Yesterday, the first annular solar eclipse in 18 years to be visible from within the United States passed straight over my house (thanks to Steve Halter for that link). 

While a partial eclipse was visible from many parts of the country, the region for viewing a true annular eclipse fell along a long rectangular strip of the western United States.  For those of us in the southwest, the eclipse was even more unusual because it happened during sunset.  The center of the eclipse path happened to slice right through Albuquerque, just a short drive south of me.  So we packed up the lawn chairs, iced tea, and sunscreen, and took a drive. 

We needed to find a spot with good views of the western horizon.  The Albuquerque Astronomical Society had just the place: it’s called Mesa del Sol.  How could we resist something so perfect?

The local meda advertised this event pretty heavily.  Thousands of people turned out to witness the eclipse.  (And I wonder how many of them are blind now.  Proper viewing glasses were in short supply yesterday.)  Another popular viewing location with good western views was Balloon Fiesta Park; I heard later that the line to enter the park was over 2 hours long at one point. 

In contrast, Mesa del Sol had free parking, easy access, and plenty of space to spread out.  And killer views.  I’m grateful to Pat Rogers, who made a full-day job of intrepid scouting on Saturday.  It’s thanks to Pat that we chose Mesa del Sol, and it couldn’t have worked out better.  Even the weather cooperated—absolutely perfect.  Not too warm, not at all windy.  Just a really lovely day all around.

The venue is often used for outdoor concerts:

But yesterday the amateur astronomers were out in force yesterday, with sun filters and end caps aplenty:

The eclipse also brought out the inner fashionista in many sky watchers:

(Photo by Pat Rogers.)

The full eclipse (from the time the moon first occluded the edge of the sun until it passed completely clear of the sun) lasted for about 2 hours.  The sun set before the whole show was finished.  But we were able to watch the onset of the eclipse all the way through the annular phase.  A cheer went up when the moon slid inside the sun’s ring of fire.  It was a long event, and it had the atmosphere of a relaxed day at the beach. 

Only 88% of the sun was covered.  That was enough to make the temperature drop noticeably as the eclipse progressed.  Combined with what would have been a brilliant sunset anyway (they’re generally pretty good here), the faux twilight had a eerie, soupy, reddish tint to it. 

Pat Rogers took this terrific sequence of photos with a digital camera and a jury-rigged solar filter made from an extra pair of cheap eclipse glasses:

At the very end of the show, the moon occluded part of the sun and the horizon cut off the rest.  The view through my eclipse glasses showed a strange, triangular sun.  It only lasted for a couple of minutes but it was very cool.