Spain/Africa Eclipse Trip
Eclipse Page

Nov 3 Eclipse Day

The November 3 2013 eclipse was a rare Hybrid eclipse.  See the explanation below for more information on Hybrid eclipses.

To summarize the longer writeup below, in a Hybrid eclipse the apparent sizes of the moon and sun are almost the same.  Where we were on the track the moon was just larger than the sun. Thus we saw a total eclipse.  Since totality for us was close to local noon, we were also almost at the point of greatest eclipse (where the moon's apparent size was the largest).

Since this eclipse occurred near solar max we expected a large number of prominences and an active corona.  We were not disappointed.  Rick Fienberg, our resident astronomer, predicted that prominences might be visible during the entire event.  That is what happened

I must confess that this is the first eclipse where I never noticed the corona.  While I was taking pictures almost continuously, the camera was preset.  All I was doing was pressing the shutter which I did without too much concentration.  What disrupted my normal viewing pattern was that chromosphere and prominences were indeed visible throughout the event.  In other eclipses I changed my view to the corona when I lost sight of the prominences.  This time my eyes were looking around the rim of the sun for the full 90 seconds.  I don't remember any details of the corona.

Heading South

We left Dakar, Senegal on Nov 1.  The weather prospects for our original site were poor so after talking with TravelQuest meteorologist Jay Anderson, the boat made the decision to target a site further down track. The target location was 05 56N  17 03W. That meant pushing the boat for more speed.  Since the engines are electric, the A/C was reduced.  We also had a very rough ride, but that was what it took

Sunrise

Not exactly clear weather at 6:48 AM. C1 was to occur at 10:50 and we were still sailing south so there was some time.

Sunrise on eclipse day

weather at 11 UTC

By 11 AM clear spots were sighted that would be on the eclipse track the boat turned and the skies opened.  By C1 the sun was in the clear. This map shows our actual location at the time of totality.  Since I could not get the location to exactly agree with our actual location of 5.751667N  16.63W the times displayed are a couple of seconds off.

Approx location of Corinthian during 2013 Solar Eclipse
NASA

Notes for all Photos

These were taken with a Canon 20Da using an EF 300mm IS lens.  My plan was to use a monopod to steady the camera. During a practice session before eclipse day I learned that the ship may be moving too much to use the monopod.  In fact, I hand held during totality.

All photos were taken at ISO 400, f/6.3 in Canon RAW mode.  The camera autofocused before C2 and then I turned autofocus off.  The shots were manual mode with 2 stop bracketing centered on 1/1000.  Times are approximate since I cannot sync the camera to seconds.  Use the times only relative to each other.

All of the images are displayed at reduced resolution.  Click for a full size image

12:28:06 1/4000 2nd Contact

2013 Solar Eclipse 12 28 06 1/4000 2nd contact

12:28:06 1/1000 2nd Contact

2013 Solar Eclipse 2nd contact

12:28:08 1/250 (processed by iPhoto)

2013 Solar Eclipse 12_28_04 1/250 processed by iPhoto

12:28:10 1/1000 (Shortly after 2nd contact)

2013 Total Solar Eclipse

12:28:10 1/4000 

2013 Solar Eclipse 12:28:10 1/4000

Processed by iPhoto and TGVDenoise via PixInisight

12:28:51 1/250

2013 Solar Eclipse Inner Corona

2013 Solar Eclipse showing outer Corona
Processed by PixInsight
2013 Solar Eclipse 12:28:51 1/250 processed by iPhoto
Processed by iPhoto

12:29:12 1/1000

2013 Solar Eclipse

12:29:12 1/4000

2013 Solar Eclipse 12:29:12 1/4000 processed by iPhoto

Processed by iPhoto. Noise reduction using TGVDenoise in PixInsight

12:29:42 3rd Contact

2013 Solar Eclipse 3rd contact

Watch Us Watch the Eclipse


Watch the Eclipse From Space

Source http://www.sat24.com/history.aspx
 

What Is a Hybrid Eclipse?

Eclipses happen at all because the apparent size of the moon and the sun are approximately the same.  The sun's apparent size varies between 31.6′ – 32.7′. The moon's orbit is more elliptical and varies between 29.3′ – 34.1′. When the moon's apparent size is at its largest relative to the sun's then a long total eclipse occurs.  When the size is smaller, like in May 2012, then an annular eclipse occurs. A Hybrid occurs when the ratio is right on the tipping point of 1:1.

The moon's apparent size changes when the earth is further away.  The size is always greatest at the noon location because the earth is curving toward the moon.  Normally this just changes the length of totality, but during a hybrid eclipse the distance is so critical that even this small amount is enough to reduce the apparent size below 1:1.  In the farthest location the moon no longer covers the sun which results in an annular eclipse. Near B the apparent size of the moon is larger so a short total eclipse occurs.

distance of moon during hybrid eclipse

Copyright


Creative Commons License
The Spain/Africa 2013 pages by Robert J. Hawley are licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported.  Use by APOD is permitted

This permits the non commercial use of the material on this site, either in whole or in part, in other works provided that I am credited for the work and you apply this or similar license to the result. Some of the included works bear a similar copyright.

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rjh 11/7/13