“How to watch the eclipse safely?” was the question that Universidad de Valparaíso’s ophthalmologist Manuel Vargas aimed to answer in a broadcast video providing instructional information on the subject. The message, an initiative of the 2020 Regional Eclipse Roundtable, aims at preventing eye damage to those who wish to watch the total solar eclipse on Monday 14th December, which will be fully visible in the Araucanía Region and partially visible in other areas of the world including the whole of Chile.
Manuel Vargas, UV Ophthalmologist
Doctor Vargas’ Youtube video begins by explaining the two ways to watch this eclipse which will draw the attention of millions of people around the world: either directly looking towards the sun using special glasses or indirectly, looking into the projection of the eclipse on a surface without the need of special glasses, using a home-made pinhole camera which, to be used safely, needs to be built following specialist instructions.
The correct glasses for watching the eclipse are ISO 12312-2 classified (also #14 welder’s glass, not available in Chile), which block the Sun’s harmful ultraviolet radiation completely and only allow a few visible light beams to pass through. How do you know whether the glasses you have procured have these protective properties? Very simple: truly suitable glasses will only let you see the sun. If a person wearing these glasses is able to see any other objects, this means the glasses are not suitable for watching a solar eclipse, as they let too much light pass through. Guaranteed specialised glasses can be found in dedicated astronomical observation shops or in websites such as American Paper Optics.
The expert also warned that eclipses should not be watched through 3D glasses, conventional sunglasses, cellophane sheeting or frosted glass, which provide a false sense of eye protection. In addition, even when using suitable glasses, you should not watch the eclipse using a photographic camera, or through a telescope or binoculars, since these instruments need their own special filters.
If children are observing this natural phenomenon, make sure that they only look at the eclipse while wearing their glasses, and that they take regular breaks, that they are not looking at the sun when putting on or taking off their glasses and that they blink regularly.
By following Dr Vargas’ recommendations you can watch the total solar eclipse safely on 14th December.
Among the institutions and organisations participating in the 2020 Eclipse 5th Region Roundtable are the Secretariat of the Ministry of Science for Central Chile, Núcleo Milenio de Formación Planetaria, Explora Valparaíso, the Aconcagua Astronomical Association, together with the Municipality of Calle Larga, the Universidad de Playa Ancha, the Secretariat of the Ministry of Health for the Valparaíso Region and the Municipality of Valparaíso, as well as UV’s Faculties of Science and Medicine, UV’s Extension and Communications Department and UV’s Institute of Physics and Astronomy.