Observers across Zimbabwe will have another opportunity to
watch one of the marvels of nature as the Moon slides across part of the Sun on
the afternoon of Sunday 3 November 2013. As seen from Harare the Moon
will touch the lower right of Sun at 3:26pm (3:25 in Bulawayo, 3:26 in Gweru
and 3:29 in Mutare). Gradually more of the Sun will be blocked out as the Moon
moves vertically upwards, reaching a maximum at about 4:20 when 37% of the
Sun’s diameter will be obscured. The eclipse ends with the Moon leaving the
upper right of the Sun at 5:13pm (5:08 in Bulawayo, 5:09 in Gweru and
5:10 in Mutare) although by then the Sun and Moon will be low in the west.
HOW TO VIEW THE ECLIPSE To observe this partial
eclipse safely a commercial eclipse viewer should be used – I hope you
have kept one from the total solar eclipses which crossed Zimbabwe in 2001 and
2002. (There are some for sale at $1 each – details below.) Alternatively you
can use a piece of welding glass. Looking through totally exposed (i.e. black)
photographic or X-ray film is risky but ok for a quick glimpse. The
safest way is to find a garage or shed or verandah with a small hole in the
roof. By the pinhole camera principle the Sun will make a small bright disc on
a piece of card held at right-angles to the Sun’s rays. At a distance of 3m
from hole to screen the ‘image’ is 25mm (or 1 inch) across. As the eclipse
progresses you will see a dark curved ‘bite’ moving slowly across the Sun’s
image.
Or you can create your own Solar Eclipse Imager . Find a piece
of plywood or card (even stiff paper will work) at least 50 cm square – the
bigger the better. Cut a small hole in the centre. I tried 5mm, 10mm and 15mm
(and it doesn’t matter if your holes are square or round). Suspend the Imager
from an overhead wire or tree with strings to hold the sheet directly facing
the Sun. Put a piece of plain card on the ground as a screen also facing the
Sun to catch the Sun’s image(s). The smallest hole gives the clearest disc but
it is also the dimmest. The largest hole makes the brightest image but it is
fuzzier. You should experiment about 3 – 4pm in the afternoon a few days before
Eclipse Day to check your imager works properly. And let’s hope it isn’t
cloudy!! Astronomers can predict to the second when eclipses will occur but
they cannot control the weather.
FURTHER ECLIPSE INFORMATION. This solar eclipse starts as an
annular eclipse in the western Atlantic at 12:04 Zimbabwe time, becoming a
total eclipse as the Moon’s shadow races southeastwards to touch the equator off
the coast of Liberia where maximum totality lasts for 99.5 seconds. The eclipse
track makes landfall in Gabon, then moves east-northeast across Congo,
Democratic Republic of Congo and northern Kenya before ending in southern
Ethiopia at 17:28 at sunset.
There is a vast amount of information about hundreds of
lunar and solar eclipses up to the year 2100 available from these websites:
www.timeanddate.com/eclipse
Click on ‘Find eclipses worldwide’ and enter any location
http://astro.ukho.gov.uk/eclbin/query.cgi
Type in any year and click on ‘Search for eclipses’
Both these websites have animations to show what the
selected eclipse will look like.
FUTURE ECLIPSES VISIBLE FROM ZIMBABWE. Partial lunar
eclipses will occur on 15 April 2014, 8 October 2014 and 4 April 2015.
Partial solar eclipses will occur on 13 September 2015, 1 September 2016 and 26
February 2017. We must wait until 27 July 2018 to see the next total lunar
eclipse, and until 4 October 2070 and 2 June 2095 for spectacular total solar
eclipses over Mutare and Harare respectively!! The next total solar eclipse
nearby crosses Namibia, Botswana and South Africa on 30 November 2030.
ECLIPSE VIEWERS are available from Dr Francis Podmore, 48
Pendennis Road, Mount Pleasant, Harare at a cost of $1 each. Telephone
04-744287 or 0772 233723 or email podmore@zol.co.zw to arrange collection.
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