Skies clear for eclipse

The Cape Town skies cleared enough for Friday’s partial eclipse of the sun to bring the crowds out onto the streets and beaches. Here are a few facts and photos from the day.

Facts about Solar eclipses

Why do solar eclipses occur?

They happen because the moon moves and passes in the direct line of sight between us and the sun.Typically 2-5 times a year.

They are only visible from certain place on Earth and it’s different for all of them. For one given city to see an eclipse, several year might pass before it sees the next one. For Cape Town, the next one will be in 2015.

There are eclipses all the time, most aren’t visible from Earth, and some are seen where no humans are living. It’s a simple geometric problem and we are able to predict them very precisely.

Sizes: angular diameter (apparent size in the sky)

About half a degree (a full circle is 360 degrees) sun diameter: 1.4 Million km moon diameter: 3500 km (400 times smaller than the Sun diameter) sun distance: approx 150 Million km (400 times farther away then the moon) moon distance: less than 0.5 Million km (385000)

Different types of eclipses

Solar eclipse only from a certain small area of the world, short time, few minutes (due to the smaller size of the moon’s shadow) Lunar eclipse: anywhere at night, a few hours. Moon passes behind Earth, sun rays blocked by Earth.

Next one will be on 13 September 2015 and it will be 30% in the Western Cape from 06h45 till 08h30am.

Never look directly at the sun, you’ll go blind. Do not use anything else than a sun viewer to look at the sun. Looking directly at the sun can blind you any day of the year, not only during eclipses.

*