Staying safe during the eclipse

Turn your back on the sun

• Thy beams, so reverend and strong—

• Why shouldst thou think?

• I could eclipse and cloud them with a wink

• John Donne, The Sun Rising, c1600.

On 11 August at 11 11 am, a total solar eclipse will occur over south west England and north west France. Its path, over 100 miles wide, leads it east and south across the continent of Europe, passing from the north of France to Munich, and thence to Bucharest and the Middle East. A partial eclipse may be visible from the north of Scotland to the north of Spain and from northern Poland to southern Italy. The eclipse will occur at the height of summer, as the sun nears its zenith, over some of the most densely populated regions of the world, and thus may be followed by an even greater incidence of retinal injury than reported after other recent eclipses.1^–5

There seems to be two mechanisms of retinal injury from solar radiation Viewing the sun through binoculars or telescopes produces the 10-25° temperature rise in the retina required for a …