[AstroNet] Eclipse viewing - NB

[Claire Flanagan]

For safe viewing of the eclipse:

 

DO NOT look through binoculars, telescope, camera, or anything that
magnifies the Sun - you will blind yourself.  Unless (see below) the
telescope is set up by an experienced astronomer, familiar with safe solar
viewing.

 

For direct Sun viewing, you need eye protection - best is eclipse viewers,
but if you don't have those then take a brief (few seconds) look through
either a double layer of Five Roses teabag foil, or three to four layers of
foil "space blanket" (available from pharmacies, used by first-aiders).

For indirect Sun viewing, by far the coolest is to look for
pinhole-projected images of the Sun in the "speckles of light" under a tree.
Details and photos at www.moonshadowmix.co.za .  For this eclipse, the Sun
will be very low in the sky.  So take a sheet of white paper, put it on a
piece of board to hold it straight, and hold it under the tree at an angle,
so the Sun shines directly onto it (sunlight shining perpendicular to the
paper).  Best trees are ones with roundish (rather than needle-shaped)
leaves.

 

Telescope / binocular viewing or projection.

This should only be done by skilled, experienced astronomers.

Telescopes should be equipped with solar filters AT THE OBJECTIVE (large)
end.  Some cheap telescopes are sold with (cheap) "solar filters" that fit
in the eyepiece.  Here, they gather concentrated heat and can crack, letting
through unfiltered sunlight that will blind the viewer.

Filters should be very firmly attached.  Finder scopes should be removed.

 

Sun projection onto a screen with binoculars or a telescope:

It must be physically impossible for anyone (including tiny children) to get
their eye at the eyepiece.  Put a barrier around the device - I've used a
cone of chicken wire between the eyepiece and the screen.

It must be constantly and vigilantly supervised.

 

Additional safety precautions that come to mind from years of dealing with
kids & the public:

* watch out for people bringing binoculars or their own telescopes - remove
these;

* watch out for people photographing the Sun - don't let them look through
the viewfinder.  It's possible (though I haven't seen it) that you damage
your camera photographing the Sun - put eclipse viewer in front of the
camera lens, and aim it while looking at the screen (not through the
viewfinder).  

 

Eclipse-viewing Events

The couple that I know of are:

* Louis Trichardt - Soutpansberg Astronomy Club

* Krugersdorp / West Rand - West Rand Astronomy Club

* KZN - Mtunzini

* Hermanus - Hermanus Astronomy Centre 

Details of the first three venues at
http://www.moonshadowmix.co.za/Eclipse2015/Eclipse2015.shtml#PublicViewing 

 

And, South African astrophotographers are planning to contribute to the
Slooh Community Telescope (on-line) telescope - http://main.slooh.com/ 

 

Enjoy the eclipse!

Claire

 

Moonshadow Mix

PO Box 731688

FAIRLAND  2030

076-744-4735

 <http://www.moonshadowmix.co.za> www.moonshadowmix.co.za

claireflan55 at gmail.com

 

 

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