Specialist glasses designed for safe solar eclipse viewing have largely sold out online, with some retailers, including Royal Museums Greenwich, reporting an "unprecedented volume" of orders. Customers are reportedly struggling to find the correct gear ahead of Wednesday's solar eclipse, which is expected to obscure around 90% of the Sun.
Experts have warned against looking directly at the Sun, even briefly, as it can cause lasting eye damage. The UK Health Security Agency (UKHA) advises that safe glasses should have the international safety standard ISO 12312-2 printed on them and be free from scratches or damage.
The Royal College of Ophthalmologists has cautioned that the retina has no pain receptors, meaning damage may not be felt as it occurs. The college also reported approximately 70 cases of vision problems following the 1999 total solar eclipse, with around 40% of those affected having looked at it for less than a minute.
Imo Bell, a planetarium astronomer at The Royal Observatory Greenwich, stated that specialist glasses are "very, very different" from regular sunglasses and block out significant light, allowing only the Sun to be visible through them.