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Eclipse on the Bounty

Robert Hawley


 


“Venus visible! Diamond Ring! A corona elongated NE to SW! Lots of prominences.”

 

The first photo shows the eclipse success flag. The second photo is taken as the sun was going into a big cloud. It did not reappear until seconds before totality. Photos by Rob Hawley.

 

Eclipses are exciting events. But nail biting is not supposed to be one of the adjectives. Heart stopping is supposed to be used to describe the beauty of the eclipse not the events leading up to it.

Solar eclipses happen elsewhere in the solar system. Spectacular eclipses only happen on earth due to the coincidence that the sun is 390 times bigger than the moon and the moon is 390 times closer. Thus they appear almost the same size. That almost was important for this eclipse. The moon's orbit is not a circle. If the moon is further from the earth an annular eclipse occurs where the sun's surface is not completely masked. If the moon is closer then a long total eclipse occurs (like in Baja). When this eclipse started near New Zealand the moon was slightly too far away so the eclipse was an annular. As the path of the shadow moved NE toward Pitcairn Island, the curvature of the earth brought the moon just close enough to cause totality. I opted to try for totality north of the legendary Pitcairn Island (of Bounty fame).

This trip was organized by ASP and had very distinguished speakers including Frank Drake (who was on the bridge during the eclipse), Alex Filippenko, Mike Bennett, and others including several meteorologists. The captain had successfully seen two before and was definitely interested in adding a third.

Eclipses at sea are good news and bad news. The good news is you can position the boat virtually anywhere on the track (if the captain is willing). The bad news is that you are at sea which means rocking, salt spray, wind, and a somewhat greater chance of low cumulus. This captain was so professional that he held a dry run the day before to see which way the boat was most stable and to check sun angles.

Eclipse day began well. The captain got to the track early after traveling east then north from Pitcairn Island (about 21S 128 W). At 6 AM our site had only scattered clouds. First contact (the beginning of the partial phase) was about 10:30 AM. We turned and headed southwest along the track (our most stable direction). By 11 AM the eclipse was progressing nicely. I had my 80 mm scope and was recording pictures of the partial phases. The air was noticeably cooler by 11:30. Unfortunately the humid tropical air reacted to that sudden cooling by forming clouds. With totality only 30 minutes away the skies turned from scattered to broken clouds.

Finally about 11:45 (E-10 minutes) the crescent sun disappeared behind a huge cloud. At that point it looked like my first cloud-out was inevitable. I forgot about my telescope and just scanned the skies hoping for a miracle. A deathly quiet descended on the ship.

Within seconds of totality the sun moved into thinner clouds and then totally into the clear. Venus visible! Diamond Ring! A corona elongated NE to SW! Lots of prominences. I watched for about 15 seconds then remembered my telescope. Seconds wasted in a futile attempt to get some pictures. I had the good sense to abandon the telescope and look up just before the end of totality. 38 seconds over in the blink of an eye.

The experts had made a number of predictions for this event. We had expected lots of beads (I did not see any with my unaided eyes, but my wife did with binoculars). The sky was pretty light and the corona was only visible about 1 solar diameter on each side of the sun. Prominences and or chromosphere were visible all around the sun. This was a very striking event.

I have been asked in the past why go to more than one eclipse. There were a lot of "eclipse virgins" on this trip. Anyone of them could now try to explain it. Eclipses are something that you experience not just observe. I am already set for Libya in 2006 (no clouds there!). It looks like in 2008 I will be joining TravelQuest in Siberia. And in 2010 the track is again close to Tahiti.

[Ed. Note: For another view of the eclipse see here. ]

 


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