Londoners will see up to 90% of the sun obscured during a rare partial solar eclipse on Wednesday, August 12.
Stargazers across the UK are preparing for a celestial event not matched in scale for decades. On Wednesday, August 12, the moon will cross paths with the sun in a regular cosmic alignment, creating a deep partial solar eclipse visible across the British Isles.
The moon is always moving, the Earth is always moving, so there's never a long period of time where the two are able to cross paths exactly, but periodically it does happen, and that's why you end up with this eclipse,
says Muller.
What Londoners Will See on August 12
In London, approximately 91.41% of the sun will be covered by the moon at 7:13 p.m. According to Royal Museums Greenwich, this marks the greatest solar coverage visible from the UK since 1999.
While the phenomenon will cause a noticeable difference in temperature and light levels, observers will not experience total darkness because the event remains a partial eclipse. Observers looking safely will notice what almost look like there's a crescent of the sun left behind, the rest will be blocked by the moon,
says Muller.
Cornwall and the Isles of Scilly Claim Britain’s Clearest Views
While London enjoys over 90% obscuration, western regions of the UK will witness an even deeper eclipse. The Met Office identifies Devon and Cornwall as top destinations, where 94% to 96% of the sun will be obscured.
Across the wider nation, coverage varies only slightly. London, Manchester, and Glasgow will see about 91% of the sun covered, while Cardiff will see 93.24% at 7:13 p.m., and Belfast will experience 93.09% coverage at 7:08 p.m. Maximum eclipse timing occurs between roughly 7:05 p.m. and 7:15 p.m. BST depending on the location, with the entire event spanning from roughly 6:00 p.m. until just after 8:00 p.m. BST (specifically between 6:17 p.m. and 8:06 p.m. according to the Met Office).
Safety Warnings From Royal Observatory Astronomers
Astronomers emphasize that standard eyewear offers no protection against solar damage during the event. Imo Bell, a planetarium astronomer at the observatory, issued a direct warning regarding safety precautions.
“It’s not a total eclipse, but over 90% is really exciting. We’re not going to get one this good for a really long time. So, it’s important not to miss it, and to be prepared. You can’t just go out and expect to have a look because it’s really dangerous for your eyes.”
Imo Bell, planetarium astronomer at the observatory
Bell noted that standard sunglasses remain entirely inadequate for viewing the phenomenon. Observers must utilize ISO 12312-2-certified eclipse glasses or approved solar filters for binoculars, cameras, and telescopes.
“You can use solar eclipse glasses, which are very, very different from sunglasses – they block out so much light that you can’t see anything through them except the sun, because that’s how much light they need to block for the damaging light of the sun to be safe to view.”
Imo Bell, planetarium astronomer at the observatory
Long-Term Outlook After August
Because the sun will sit only about 13 to 16 degrees above the west-northwest horizon at maximum eclipse, experts recommend arriving early at hilltops, cliffs, beaches, and other locations with unobstructed western views.
For those who miss the August 12 event, opportunities for a comparable viewing window will remain sparse for decades. The UK will not see another deep partial solar eclipse until September 3, 2081, while the next total solar eclipse visible from the UK is due on September 23, 2090.
The event also comes just hours before the annual Perseid meteor shower reaches its peak on the same night. Because the peak occurs during a new moon, conditions are ideal for seeing the peak, notes Royal Museums Greenwich, creating one of the best nights of the year for skywatching.