There is a solar eclipse due to occur in Ireland on March 20th. Though the eclipse will not be complete this far south (there is only a small area near the Arctic circle where it will be), it should still be a fairly spectacular and rare sight.
Issac Newton is one famous person who damaged his sight by looking at the sun, and every eclipse event causes a number of people to present to eye departments with problems caused by Solar Retinopathy. Everyone knows that you can set alight a piece of paper on a sunny day, even with a small magnifier such as on a Swiss Army Knife, but fewer people are aware that it can cause sight loss.
Solar Retinopathy is often called a retinal burn, but it is actually not caused by direct heating, but is a photochemical reaction to the intense sunlight. Normally trying to look at the sun causes us to peer- squeezing our eyelids closed and the pupils constrict, which can be uncomfortable – the discomfort is discouragement enough to not look at it, but during an eclipse, when the sun doesn’t seem so bright, these protective mechanisms do not work quite so well. There is also of course a better reason to want to look than there normally would be!
Though solar retinopathy can often recover, it can cause lifelong diminution of vision- do not take the chance. Do not look directly at the solar eclipse. As the event is happening early in the morning, when the sun will be lower in the sky, there may be less risk of damage than at midday, but as the complete eclipse from start to finish will last about 2 hours, there is still a risk of sight damage.
It is best to view the eclipse indirectly, by projecting an image onto the ground or a piece of paper, though it is also possible to buy inexpensive eclipse viewing shields which will give the required protection. Certain welding masks may also give the required degree of protection. No standard sunglasses are suitable to look at the sun- the direct eclipse viewing shields absorb 100% of UV and Infra Red radiation, and 99.999% of visible light!
Of course, this is Ireland – the whole thing will probably be clouded over and completely invisible.