3 October 2005: the Ring of Light!

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The ring of light

As expected, around 11.00am CEST second contact takes place The Moon, due to its angular diameter being significantly smaller than that of the Sun, gets completely engulfed into its dazzling light. The totality phase has begun, and it will last a tad more than for minutes; the ambient light reaches its minimum value. While continuously shooting the Sun (the annularity phase calls for more than 30 frames, and the whole eclipse coverage will take more than twice as many), a strange phenomenon catches my eye: all shadows have blurred contours, as if they were surrounded by strange haloes. In fact, this situation can be easily explained as follows. If we illuminate an object with two distinct light sources (i.e. two lamps) being a certain distance apart, we will get two different shadows: by generalizing, we get as many distinct shadows as there are light sources. But if we arrange all these light sources to be very close to each other at about the same distance from the object being illuminated, all the resulting shadows will be very offset by the same small amount. The ring of light made by the eclipsed Sun can be thought of as being made up by an infinite amount of separate light sources, thereby casting those fuzzy, "concentric-haloed" shadows.

Three consecutive moments of the annularity phase. From left to right: 11:00:20, 11:02:28 e 11:04:20 (am, CEST)

As compared with the August 1999 total eclipse, a significant difference in climate behavior must be pointed out. Back then, a big temperature drop (about 5-6 °C) was recorded: this time, temperature during totality didn't decrease that much (lowest of 13 °C from an initial value of 14 °C). This most likely happened for two reasons: cloud cover and steady wind had prevented any significant thermal increase from taking place until mid-morning, and a small amount of sunshine always reaches the ground, since the Sun is never completely obscured. Later on, I checked out the temperature records for different nearby locations on the Internet, which suggest a daytime peak not higher than 20 °C.

Unfortunately, the annularity phase is really too short: as soon as it's over, we can have a little rest while shooting the final stages of our eclipse sequences.

What happens when we punch a hole pattern into a map to form the "SPAIN" word? We get the same word, made up of small Sun crescents!

Myself while fine tuning the position of my MTO

Just moments past 12:30 pm CEST, the outer limb of the Moon leaves our the Sun, being engulfed into the latter's dazzling light. Standing in awe, we wonder if everything is really over, or if Mother Nature bothered to provide our planet Earth with another Moon-like satellite to give us an encore...

Epilogue

The full "eclipse buster" team. From left to right: Lorenzo Comolli, Alessandro Gambaro, Alberto Gianni, Marco Scardia and I.

Well, I must say it has been a very thrilling adventure... although we'd probably live without the vagaries of the weather :-); nevertheless, a little suspense made our trip more exciting. It surely was too short, but all our pictures of this wonderful event will remind us of it for a long time to come: everyone of us will keep his very personal memories that won't easily fade away.

While packing up, we take the chance to have a little chat with other fellow amateur astronomers: most of them come from ouside Spain (mainly France and Germany) and have travelled all the way down to southeastern Spain to witness the eclipse. Now, it's time to have a good Spanish lunch before starting our 1400-km trip back to Italy.

Greetings to everybody and see you all at the next eclipse!!

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