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| 29 Mar 2006 - Eclipse Day
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 | | show all 17 | | Dawn on eclipse day. Notice Venus to the right. | | Anticipation. We almost had the desert to ourselves and not a cloud to be seen! | | 0935UT: 25 minutes after 1st Contact. | | |
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After what little
sleep I had, I stepped outside the tent at around 5am to visit
the conveniences, and was greeted by a fine sight of the Milky
Way, with the bright galactic centre in Sagittarius, too low
to see properly from the UK. Venus, ridiculously bright, was
also rising in the east. I didn't mean to get up so early, but
having done so I went to the edge of the camp to get beyond
the worst of the lights to watch the dawn and look for Mercury.
There was not a cloud in the sky - as it was to remain all day
- but Mercury did not reveal itself to the naked eye in the
rapidly lightening sky, so I returned for a little more "sleep".
People began getting up at around 8am, and during and after
a picnic breakfast I began to assemble
my two Helios telescopes - the tripod legs from the bottom of
my case and the mount and business end from the metal briefcases.
Meanwhile, the Jackson kids, Charles and Josie, were despatched
with their Dad Brent to fill up the two bags I brought to act
as counterweights on the equatorial mounts. About a kilo of
sand would do on the scope for visual use and a kilo and a half
for the one to which I would attach the camera, but they enjoyed
filling them with desert pebbles instead, a few of which I have
kept as souvenirs of the big day.
At around 10am, 70 minutes before first contact, the astronomers
/ eclipse veterans amonst us (principally Michael, Phil and
myself) gave a short talk on what to expect and how to safely
view the event with the eclipse glasses provided and the various
pieces of equipment we had brought with us. We then headed off
into the desert taking our equipment, plus water, chairs and
a table, with us. We headed south for around 400m as we judged
this direction was upwind of the camp (less dust equals clearer
skies) and just far enough to avoid any crowd developing around
us. As it turned out, other people seemed to be quite thinly
spread out and there were no crowds at all - I think a good
many people actually decided to watch the event sitting outside
their own tents.
Before the start of the eclipse, those with equipment were busy
setting up telescopes and cameras, and assisting those with
basic cameras to get the best out of the forthcoming spectacle.
There were only three telescopes amongst all of us - my two
plus Dean's 5-inch
Celestron, just about manageable on a small tripod, a fair
few had cameras with good lenses, while Phil and Sonya were
each going to attempt to video the event. Amanda and Michael
were also interviewed
for Libyan TV - the crew were fascinated that people had come
from as far away as Australia to see this eclipse.
First Contact was due at 0909UT (11:09 local time) and I confirmed
moments later that the first bite out of the Sun had indeed
appeared - as I saw it in the telescope, on the left hand side.
With the naked eye or binocular view the Moon would travel from
lower right to top left (west to east) across the Sun, and I
have orientated all the eclipse photos on this page accordingly.
There was a steady queue of people at my visual telescope to
monitor the progress of the Moon creeping across the Sun. This
I equipped with a Baader Planetarium mylar filter, which gave
the Sun a rather eerie blue colour, while I reserved by Orion
glass filter for use with the camera so the Sun's appearance
would remain in keeping with my pictures from previous eclipses
- the more natural colour here also attracted viewers. Three
small sunspots were also visible towards the eastern limb of
the Sun, which might provide some interest as they are eclipsed
and may perhaps create some flames (Prominences) in the Sun's
outer atmosphere during totality.
With the activity, the interval between First and Second contact
seemed to pass quickly, but in truth was unusually long at 1h
25m. Normally the Moon covers its own (and Sun's) diameter in
around an hour, but with the time approaching local noon, and
with us being just 28 degrees from the equator, we were really
benefitting from the Earth's rotation (around 900mph / 1400
kph) carrying us substantially in the direction of the Moon's
shadow, thereby extending the duration of the partial and total
phases.
By 0945UT (11:45 local) the Moon had reached nearly 50% of the
way across the Sun and it clear that the temperature was starting
to fall and that a gusty wind was getting up. Although not rigorously
scientific, I asked Judith, who had a Nokia mobile phone that
measures remperature, to keep an eye on the temperature during
the eclipse, and it recorded a drop of 11 degrees centigrade
from 34 degrees at 1000UT (12 noon local) to 23 degrees at 1025
(1225 local), moments before totality.
It was also becoming apparent that the light was beginning to
change, especially the brightness of the sky. This was much
earlier than I had noticed in previous eclipses and was perhaps
something to do with our exposed location and unusually clear
sky. At around this time Venus, some 40 degrees west of the
Sun, began to become visible, and by 1000UT (12:00 local) was
appearing quite bright. Fun was also had observing our shadows,
getting more intense and sharply defined as the Sun grew thinner,
and projecting images of the narrowing crescent Sun on the ground
using binoculars and assorted holes in things like hats.
In the last minute or two before totality, due to arrive at
1026:38UT (12:26:38 local), the air of excitement and anticipation
grew as the Sun diminished to an ever thinner crescent and the
sky began to darken seriously. In the dying seconds, people,
myself included, struggled to see Bailey's Beads. These are
the last remnants of the Sun's bright surface (the Photosphere)
broken up into individual spots of light as it shines between
craters, valleys and mountains on the Moon's surface. As I had
anticipated, and warned people, they were almost impossible
to observe with the Sun high in the sky, because while the Sun
had all but disappeared when seen through viewers, it was still
too bright to look at directly.
Then, suddenly, darkness was upon us as the edge of the Moon's
shadow swept over us, and totality had started. I got no impression
of the shadow sweeping across the desert - it was just too flat.
That is something I have yet to experience and will have to
wait for another eclipse!
Eclipse viewers and filters off! It was time to look at the
Sun directly as the corona flashed into view. For many in our
party this was their first total eclipse, and for all of us,
the moment of truth after the months and years of planning and
expectation had finally arrived. And what a beautiful sight
it was - the black disk of the Moon surrounded by the silvery
white corona, fairly evenly distributed around the Sun, and
with the Sun's magnetic poles picked out by fine hairs or filaments,
very much as you would see with iron filings laid on a piece
of paper over a bar magnet. There was also the impression of
arms extending away into space giving the corona curious, almost
rectangular appearance.
Looking around, it had become almost night, with the sky a deep
blue-grey apart from an orange-pink sunset that extended around
the entire horizon. This was sunlight spilling in from beyond
the Moon's shadow, the edge of which was some 90km away at mid
eclipse. People in fact complained later that it had become
so dark they could not read displays on their cameras, and Paul,
who had the terrible misfortune of running out of film at the
precious moment, could barely see to change over to a new one.
To the west Venus shone brilliantly, just like it had done before
dawn. Some people later said that they had thought it was an
aircraft or a balloon, not believing it could possibly be so
bright. Between Venus and the Sun lay Mercury, but harder to
see. I did not definitely see any other stars, though must confess
that I did not spend long looking.
With all the excitement the 4 minutes 3 seconds of totality
were in danger of passing without my taking any photographs,
but I also wanted to see the eclipse through my other telescope,
never having seen a totality close up before. I grabbed a selection
of shots at different exposures to try to capture different
aspects of the corona, then went for a look through my other
telescope, where there was plenty of activity under the control
of Rebecca, who I had put in charge of removing and replacing
the filter at the appropriate moments.
The view through the scope was incredible, with the hair-like
streamers of the corona picked out in much more detail than
with the naked eye, and, it has to be said, better than any
photograph. Totality was nearly over by now so there was a noticeable
brightening on the side of the Moon where the Sun would reappear,
and the pink outer atmosphere of the sun (the Chromosphere)
was emerging adjacent to the edge of the Moon. Along it, in
a few places, fiery Prominences stood proud of the surface like
pink flames.
I dashed back to my other scope to catch the dying seconds of
totality (due to end at 1030:42UT (12:30.42 local)) and catch
the spectacular Diamond Ring as the first shaft of sunlight
bursts back onto the scene. After getting used to the darkness,
it was certainly a stunner when the Sun reappeared, but I wasn't
sure whether my camera's image chip would survive the punishment
of being subjected to full sunlight though the telescope in
what was a very "fast" optical system - only f/1.5 at the current
setting. I had the rest of the Libya trip to think about, so
I hastily replaced the filter after grabbing one shot of the
Diamond Ring, but I hope you'll agree that the result was worth
the risk.
Bailey's Beads were again elusive - better to wait for an eclipse
with the Sun low in the sky for this - but instead we were rewarded
with a fine display of Shadow Bands. Turning away from the Sun
the desert surface was alive with subtle wavy light and dark
bands, very much as the shadows of ripples appear on the bottom
of a swimming pool. They were perhaps 6 to 9 inches (15 to 25cm)
apart and moved steadily eastwards at around 1mph (0.5m/s).
I called out for people to watch this elusive phonomenon and
grabbed a couple of photos with my small camera but the results
were disappointing and unconvincing. The contast was quite subtle
and was is the movement that made them clear to the eye - a
better target for video really. They are images of the thin
cresent Sun created by turbulence in the atmosphere, but had
disappeared by around 30 seconds after totality, by which time
the sky and surroundings were brightening rapidly.
The beating of drums sounded out from the camp - the eclipse
dance had worked and normality was returning as the shadow continued
its rush north-eastwards across Libya and beyond. Of course,
the wait for Fourth Contact, when the Moon finally clears the
Sun (due at 1150UT (01:50 local) was something of an anti-climax
after the build up to totality, and with lunch scheduled at
1:15pm - a priority given the shambles of last night - so after
a group photo most of our party began to pack up and head back
to camp by about 1pm. Only the die-hards, myself included, stayed
to the end, but we need not have worried because by the time
we arrived at the lunch tent at around 2pm, serving had still
not started. Indeed, scuffles were breaking out by the door
as those relegated to a second sitting, mostly Libyans it seemed,
were naturally getting impatient at the delay.
The form for lunch was pretty much the same as for dinner last
night, albeit it with less chaos. The camp management were on
hand to wish us well and give an apology, which I think was
largely accepted. It was clear from the outset that this was
a major undertaking given that Libya does not have much of a
tourist infrastructure and certainly no experience of catering
for such large numbers of people, especially in the middle of
nowhere like this.
Later, some of us found shade to take it easy, talk of the morning's
events and discuss the prospects of future eclipses, while Roger
headed off into the desert for a walk in the noon-day sun, perhaps
never to be seen again. Michael, Phil and I went to explore
the camp further, looking at souvenirs, and eyeing up enviously
the more luxurious accomodation provided in the some of the
other sections of the camp. We came across a French astronomer
with his 20-inch telescope on the back of a pick-up truck, taking
a break from surveying sites in Libya for an observatory (though
the desert here would not be one of them!), and found a well-appointed
internet tent, to which I returned later in the evening to upload
pictures and a brief update to this journal.
Many other people left after lunch and there were convoys of
vehicles leaving camp along the dusty road. It was to our advantage
though, as come evening we had a wide selection of tents to
choose from so most of us moved into more spacious accommodation.
After dinner, about eight of us went out of the camp to try
to escape the lights and have an observing session. It was a
welcome chance for the Australians to see the northern sky,
for me to see a sky further south than usual, and for those
less familiar to have a quick tour of the sky and look through
my Helios telescope and Dean's Celestron at variety of objects.
Some targets were Jupiter and Saturn, some star clusters including
the Beehive, Pleiades and Omega Centauri, some galaxies and
the broken comet 73P / Schwassmann-Wachmann. For the latter
the eye of faith was definitely required as it was still very
faint at 9th magnitude, but may put on a good display as the
3 fragments pass very close to the Earth towards the end of
May.
There were still too many lights to catch the Zodiacal Light,
and we were also disturbed by people in vehicles, headlights
blazing, coming to see what we were up to, which did nothing
to help our night vision. Also, we would have to wait until
the early hours of the morning to catch the Milky Way, but there
will be other opportunities for that. Nevertheless we had a
good evening, a fitting end to a great day! |
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