Sunday, July 11, 2010

Waiting for The Total Eclipse of the Sun

Current Location: SE Corner of Tahanea, Tuamotus, French Polynesia

Tahanea's SE Corner And the Edge of Totality
Optimum Viewing Spot on the Left, our Anchorage on the Right
Blue Line Shows Edge of Totality

We have been anchored here for a few days now, enjoying the solitude. We are not completely alone any more. A Canadian boat whose name we can't quite read with the binoculars, came in 2 days ago and anchored about a half a mile away. They, like us, have been mostly hanging out on their boat doing 'boat chores'. We were going to swing by yesterday in the dinghy on our way ashore, just to say hi, but we were running out of daylight before we finally got in the dinghy. Maybe tomorrow.

A third boat came in sometime yesterday. They anchored so far to the north of us that we didn't even know they were there until we saw a dinghy go by. "Where did that come from?" We had to get out the binoculars to see them.

But now we have met them. It is a boat from Dream Charters' charter fleet, with 5 scientists from France, here to study the eclipse. It is a 52-foot Jeanneau-style sailboat. They were running around in their dinghy looking for diesel fuel--they had planned to refuel in Makemo but found they could not obtain any until the supply boat came in a few days. So we sold them 10 gallons from our precious stock, and then were invited to help them out with their scientific observations.

Dr. Lydie Sichoix, Associate Professor from the University of French Polynesia, Shows Us a Photometer

Apparently, a total eclipse is a great way to measure the diameter of the sun. So their task is to place photometry devices around on the atolls to record the time and location of the eclipse. The eclipse is making a swath of totality who's northern border is just going to cut across the SE corner of Tahanea, where we are. That makes Tahanea a prime measurement spot.

So yesterday, we loaded up on their boat and went down to one motu in the extreme SouthEast end, and anchored temporarily to plant 4 Picali Photometre Solaire devices. Then they are going to leave one of the scientists with us today, and sail to another atoll 20 miles away to observe the eclipse from there (Motutunga). We will keep Lydie with us, take her to the proper spot to observe the eclipse, and then retrieve the photometry devices. When they return from Motutunga, they will take Lydie and the photometers and leave immediately for Fakarava.

Setting up the Photometers

Checking the Angle Precisely

The Photometer Set Up

It is still blowing like stink here (20+ knots) from the East. In lighter winds, we would go down and spend the night at the proper spot, but it is really rough down there. So we will spend the night tonight anchored comfortably here in our sheltered spot, and then get up early and go down at first light (about 5 miles away). The eclipse will start at about 0720 am and reach totality about 0824am here on the 11th (actually 1824 UTC).

(These calculations came from, for location 16.9871S 144.6639W))

We are just on the very edge of the path of totality, so the scientists say that we will only have totality for about 10-20 seconds. Dave is going to take our camera and try to take pictures. And the scientists gave us some plastic viewing glasses. They are similar in form to the cardboard glasses you get at 3D movies, but with much darker plastic--made for viewing solar events.

We have also been issued chronometers supplied by a professor at Yale University, to time the totality. One of the things being studied is how the irregularity of the surface of the moon (which is causing the totality) affects the eclipse, and their efforts to measure the diameter of the sun.

We are excited to actually be involved in a scientific experiment, rather than just hanging out here drinking beer!
At 7/8/2010 12:14 AM (utc) our position was 16°57.21'S 144°34.83'W

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