High street retailers are reporting a sell-out of solar eclipse glasses as demand surges among skywatchers preparing for an upcoming celestial event. Online shoppers are also facing delays, with some delivery estimates extending to the end of the week. The phenomenon, described as a 'once in a generation' occurrence, will see up to 96% of the sun obscured.
The Royal Observatory Greenwich has confirmed it has sold out of solar eclipse glasses both online and in its physical stores due to an "unprecedented volume of orders." British retailer Robert Dyas also listed Bresser eclipse glasses as out of stock on its website.
Neil Sanders, founder of Go Stargazing and UK coordinator for Astronomers Without Borders, suggested the shortage stems from a lack of advance planning rather than a lack of available product. "Everyone's suddenly realising we need glasses for Wednesday," Sanders told The Guardian, referencing the numerous inquiries he has received.
The solar eclipse is scheduled to begin shortly after 6 p.m., with the exact timing varying by location. Maximum coverage is expected approximately one hour later, leading to a period of premature twilight before the event concludes just after 8 p.m. The eclipse will start in Glasgow and Edinburgh at 6:06 p.m., in Manchester and Liverpool at 6:13 p.m., in Birmingham at 6:15 p.m., and in London, Bristol, and Cardiff at 6:17 p.m. Cornwall will experience the start at 6:18 p.m.
Viewers, with appropriate safety precautions, will observe a small portion of the sun being obscured, gradually increasing to cover most of the solar disk. At the peak of the eclipse, only a small, inverted crescent of the sun will be visible. Dr. Megan Argo, an astrophysicist from the University of Lancaster, noted that the UK will experience a deep partial eclipse, with over 90% of the sun covered in many areas. "Even though the sky won't go completely dark, it's still an unusual and memorable sight, and it's set to be one of the best partial eclipses visible from the UK for many years," she told the Daily Mail.
The extent of the obscuration will differ across the UK, with southwestern regions experiencing a deeper eclipse. Bishop Rock in the Isles of Scilly is predicted to have the most significant coverage at 96.5%, while Land's End and Lizard Point will see over 95%. Coverage will be around 91% in London, Birmingham, Manchester, and Edinburgh, and approximately 88% in the Shetland Isles.
Experts advise that safe viewing requires certified eclipse glasses, specifically those with the 'ISO 12312-2' or 'ISO 12312-2:2015' certification and a CE or UKCA mark. Indirect viewing methods, such as projecting an image of the sun through a colander or a piece of paper, are also recommended.
Separately, Octopus Energy has urged its 8 million customers to reduce electricity consumption between 6 p.m. and 8 p.m. during the eclipse. The company warned that the event could significantly reduce solar power generation, potentially necessitating increased reliance on fossil fuels. The National Energy System Operator estimates that solar supply could drop by up to 1.3 gigawatts, enough to power over 500,000 homes. Octopus Energy has offered one hour of free daytime electricity on the following Sunday to customers who consciously use less electricity during the two-hour window.