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The 2006 total solar eclipse from the Sahara desert, Libya ...
The eclipse I witnessed with Andrew Huggett, Jason Woolley, Zeineth
Ali plus Roy and Shirley Sturmy was my third and most definitely best
event. Shown below is firstly, a transcript of the dictaphone recording
I made leading up to and during the eclipse and secondly, a copy of
the Sky and Telescope magazine article (August 2006) from Stephen James
O'Meara's column, featuring my observations.
Why not listen to how exciting a total eclipse of the Sun can be? Click
to download (1.6mb). Right-click (Windows)/Ctrl-click (Macintosh)
and choose 'Download link to disk'.
The UT times expressed here may not be completely accurate, though I'm
sure I checked. Entries shown in quotes are my actual comments to
my colleagues. I've spared you from absolutely everything I said ... Unfortunately,
there are a lot of exclamation marks, but I've tried to keep the
written record as accurate as possible.
0928 UT
Sky inspection: beautiful mid-powder blue, no clouds.
Quality: hazy to horizon, Sun bright white.
Limb inspection: Advancing limb pale mid-blue with the upper limb (at
2 o'clock) green tinged. Sunspots look wonderful, including faculae. Three
maybe four spots. Umbra and penumbra visible. * This observation was made
through my camera viewfinder attached to 'scope, so may be inaccurate.
It's breezy.
0941 UT
Towards half-phase.
Briefly glancing at the Sun with sunglasses shows the phase.
Wind has subsided.
0946 UT
Sky inspection: now a little different - a deeper blue, no clouds.
Quality: unchanged; seeing fairly steady
Limb inspection: no discernible difference. * Again made through
my camera viewfinder attached to 'scope, so may be inaccurate.
'Things are now starting to happen more quickly.'
My extreme hunger has completely disappeared! I have had no food since
0030 UT. Thankfully I have water.
0951 UT
'Absolutely beautiful'
post 0957 UT
The Moon's very wide shadow can be seen funneling down to the horizon.
If I sweep my head from side to side I can see it more clearly.
1000 UT
Shadows: with my back to the Sun, the left-hand side of my shadow is diffuse,
the right-hand side sharp. They're changing as time progresses.
Sky inspection: the colour of the sky is definitely changing - it's
a deeper blue to the Southwest (no doubt due to the Moon's shadow), no
clouds.
Quality: same, but dust clouds are now more apparent.
Temperature: getting cooler
1004 UT
Limb inspection: the leading limb of the Moon is now approaching the first
sunspot.
It's easy to see the solar crescents when I cross my fingers on both hands. The
wind has returned and has increased.
1010 UT
Shadows: very tight.
'Just look at the light, folks - it's absolutely crazy! Only 15 minutes
to go.'
The approaching shadow of the Moon is huge. There is a purple hue around
the horizon like the Belt of Venus. We spot the planet Venus without
any problem.
1011 UT
Shadows: are extremely sharp.
The texture of the desert had changed previously but now it's very apparent.
It is almost as if you can see the individual grains of sand. The ground
looks semi-transparent - almost as though it is polarized (as if wearing
sunglasses). I can still see mirages. There is a small Belt of Venus-effect area
directly opposite the Sun and to the right-hand side of the Moon's
shadow.
'It's getting quiet now. There's definitely a hush about the place.
People are sensing something is going to happen. About 13 minutes
to go.'
1014 UT - approx
'Look at the Moon's shadow - WOW! - you can really see it! How dark
is it now?! I really don't know what to do with myself ... Look at
the highlights on things! They look incredibly bright. It's
incredibly still. Venus looks so very silvery. The Moon's shadow
looks like a storm!'
The corona is already visible, just the very inner part. The wind is gusting.
'Look at the crescent, folks! We're really close.'
1020 UT - approx
'Just over five minutes to go! Unbelievable. It's *so* dark. The
Moon's shadow is breathtaking ... Good grief. The Belt of Venus -
the colour of the horizon - Oh god!'
I go to see the 'beading' cusps of the crescent as shown in a Coronado
PST.
1024/25 UT - approx
'It's about upon us guys, I'd settle down and get ready ... Really
close. Oh, good grief look at the Belt of Venus, oh, WOW!'
- Time gap -
'Shadow bands! Shadow bands, YES! Less then a minute ... Oh, look
at the shadow bands NOW. Look at the shadow! Oh my goodness. Look at that!
Oh! Shadow bands WOW ... Look at the colour of the sky ... Oh, diamond
ring! Look at that! Woohoo! Oh, oh my goodness. Oh, that is ... Look at
the corona! Oh dear, oh my goodness - that is so, so beautiful. Look at
the horizon! You're right in the Moon's shadow now. Just look at the colour!
The Moon's shadow is still coming ...'
- Time gap -
'Mercury, Mercury guys - between Venus and the Sun. Oh ... Can you
see any prominences? I can't. Look at the shape of the corona, how spiky
and uneven. The streamers! Look at the colour around us! I'd say we're
about mid-eclipse now. About mid-eclipse.'
- Time gap -
'Brightening ... Going to get the binoculars out now. Oh, oh my goodness
- that is UNBELIEVABLE! Can you see the details in the corona? WOW,
the streamers! Oh, oh, oh ... The shadow's moving way soon ... I can see
1, 2, 3, 4, 5, 6, 7, 8 streamers, and the poles are full of striations!
I can see one prominence at four o'clock ... And a second. It's brightening
up guys. Get ready, you're going to get the diamond ring soon ... Ah, savour
it, it's going! There's the diamond ring! There's the diamond ring!
Shadow bands again! That's it. Shadow bands, still! Ah ... Look at the
horizon going away from us! Look at the colour - Moon's shadow going AWAY!
WOW! Was that four minutes?! Was that four minutes?! Look at
the dust on the horizon ... '
- Time gap (Lots of cartwheels, shaking of hands, hugging and whooping
follow) -
'Oh, what a headache! Oh god - number three! That was absolutely
awesome. Actually it wasn't as dark as I thought it would be. What did
you think of the (sky) colour? Purple? Oh, I need a drink ... (water,
of course!) '
----
A British amateur turns a total solar eclipse
into a total experience.
Greenwood’s Exceptional Solar Eclipse
In last April’s issue (page 64), I offered an eclipse timetable
to those traveling to the March 29th total solar eclipse, to help them
get the most out of seeing the event. Andrew Greenwood, chairman of the
Macclesfield Astronomical Society in Britain, found the checklist of interest
and incorporated aspects of it into his own observing and imaging schedule.
He also used a dictaphone to recount the times of his observations. As
a result, he was rewarded with several surprises. Here are some of his
more outstanding observations.
Greenwood observed totality from the Libyan Sahara, about 50 miles south
of the oasis town of Jalu. The landscape was 'very alien,'
he says, 'a flat, lifeless, expanse in all directions, which added
a certain intensity to the experience. All the normal visual aspects of
the eclipse, seemed heightened at least twofold. I have no doubt that
this was due to the environment. Being in the middle of the Sahara was
truly inspiring.'
The first surprise Greenwood experienced was the arrival of the oncoming
lunar shadow. Commonly observers look for it on the western horizon when
the Sun is about 80 percent eclipsed. But Greenwood first detected the
'urn-shaped shadow' well before the Sun was 50 percent eclipsed.
And while bright planets like Venus usually become readily noticeable
to the unaided eye about 10 minutes before totality, Greenwood found -4.2-magnitude
Venus, which was 46ù west of the Sun, 'incredibly obvious 15 minutes
before totality. I envisage that it would have been an easy naked-eye
target well before this,' he says.
Shadow bands are arguably the most elusive of all eclipse phenomena, mainly
because so much drama is unfolding in the sky when they first appear on
the ground that they are easily overlooked; and so much emotion wells
up when totality ends that many people forget to look down for shadow
bands after third contact. But the timetable helped Greenwood see 'the
most prominent and lengthy apparition of shadow bands I’ve ever
seen. They occurred 43 seconds before second contact, and the quality
of the bands was incredible,' Greenwood says. 'They were very
contrasty and fairly hard-edged.' Upon reflection, he says they
were about 1 to 1.5 inches in diameter and spaced about 3 inches apart.
'You could almost feel them!' he says. 'It was very
much like being underwater in a pool with the refraction from the ripples
above.' He spotted them again 6 seconds after third contact.
Greenwood says, 'Totality was awesome, the best I have seen.'
While he managed to take 58 exposures during totality, he still afforded
at least 1.5 minutes to watch the 'glorious spectacle' with
his unaided eyes and binoculars. He also scanned his surroundings during
totality and recorded the colour and quality of the earth and sky.
'The colours were especially vivid,' he says, 'being
quite saturated and intense. The gradations of colour around the horizon
were so much more striking than those during a normal sunset. A fellow
observer saw the horizon colour as a fiery-orange; to me it was much more
intense. The sandy surface was a deep ochre-orange, as if a piece of orange-yellow
cloth was placed in front of a warm-toned light bulb. And the sky around
the eclipsed Sun was a definite blue-purple. This is somewhat conflicted
by the composite image I made and others I have seen, where the sky looks
more of a dark steely-blue. Perhaps the camera does lie!' Confirming
the apparent darkness of the sky, Greenwood also spied 1st-magnitude Mercury
between the Sun and Venus and 1st-magnitude Mars 72ù east of the Sun,
neither of which were expected to be seen (at least with ease) during
this particular eclipse.
The Cheshire Frown
'The most amazing observation, however,' Greenwood says, 'was
that of the pre-totality corona.' He had seen it before with the
unaided eye during the 1999 and 2001 total solar eclipses, but only about
a minute or so before totality. This time Greenwood spied it telescopically
about 10 minutes before totality. 'With the Sun’s partial
phase out of the field of view,' he says, 'the corona was
clearly visible. I now wonder how much sooner I could have seen it. It
wouldn't surprise me if the corona could have been detected 20 minutes
before totality under excellent clarity.'
Greenwood’s guesstimate is not far off. From the Libyan Desert,
near Salloum, Egypt, with the Sun at an altitude of 68ù, I followed the
corona with the unaided eye for 14 minutes after totality by placing the
waxing crescent behind the intersection of two wooden tent poles. The
corona was quite comfortably seen until only about a minute before the
densest part of the corona turned into a whisker-thin frown that gradually
faded away like Lewis Carroll’s whimsical Cheshire-Cat.
Andrew Greenwood
Click on an image to see a larger version.
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 July and August updates ...
The bright twilight nights are slowly giving way to darker skies and the prospect of revealing a little-known nightly sight. Away from the towns and cities, the Milky Way will soon be glimpsed meandering through the constellation of Cygnus. This river of stars was worshipped by the ancient Egyptians ... Nowadays, especially when we approach the end of Summer, it's astronomers that turn their gaze skyward and praise the sight of a myriad of stars arching high above them.
The following sections have been updated: This month's night sky and observations.
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