The third of four eclipses in 2015 will occur this Sunday, September 13. It will be a partial eclipse of the sun, and unfortunately it will be visible only from southern Africa, the Indian Ocean, and parts of Antarctica.
The best view of this eclipse from an urban area will be from Cape Town, South Africa, where a maximum of 30 percent of the sun will be covered by the moon.
The eclipse begins in Cape Town just as the sun and moon are rising at 6:49 a.m. local time. Early risers will see a tiny bite out of the sun. It reaches its maximum at 7:43 a.m. By 8:50 a.m. the eclipse will be over.
This eclipse will be visible throughout South Africa, and also in southern parts of Madagascar, Mozambique, Zambia, and Zimbabwe. It will also be visible over a wide area of the Indian Ocean, and Antarctica (if you happen to be a penguin).
The best way to observe a partial solar eclipse is with a filter specifically designed for observing the sun, sold by stores specializing in telescopes. Safe “eclipse shades” are often widely available prior to an eclipse. A number 14 welder’s glass also works well, and is available from specialized welding shops. The ordinary number 12 welder’s glass sold in hardware stores does not provide adequate protection.
If you don’t have a proper solar filter, you can view the partially eclipsed sun with a pinhole camera by punching a hole about a millimeter in diameter in a piece of cardboard. Natural “pinholes” created by leaves on trees or reflections from a building’s windows will also work.
Under NO circumstances look directly at the sun, even with sunglasses, as you can quickly cause permanent damage to your eyes. If a small magnifying glass can light a fire in seconds, think what will happen to the retina of your eye by staring at the sun.
As always, we welcome your pictures of the partially eclipsed sun; a solar filter on your camera will be essential. The sensor in your camera is just as easily damaged by the direct sun as your eyes. Try to get a landmark or tree in the foreground to give a sense of scale.