Don't Miss This Month's Partial Solar Eclipse!
- Justin
- Mar 18
- 3 min read
On Saturday 29th March 2025, a partial solar eclipse will be visible across the UK. Solar eclipses in the UK don't come along often, although this one will be the first one of a series of six solar eclipses that we'll get in the UK over the next six years. [1]
To make the most of the opportunity, here are some tips on how to view the partial eclipse for yourself.
What can I expect to see?
The eclipse lasts for approximately two hours in the late morning, with exact timings varying by location. At the maximum point of eclipse (at around 11:00am), the sun will be a thick crescent shape, with around 30% of the sun covered by the moon for viewers in the South East of England, increasing to over 45% coverage in the North of Scotland.
To find the exact timings for your location, and to see a preview of how much of the sun will be covered, this tool on The Sky Live website is very useful. [2]
Because most of the sun will remain uncovered throughout the eclipse, the sky won't become noticeably darker, as happens during a total eclipse. Since the sun is so bright, daylight doesn't start to become appreciably dimmer until the eclipse gets past about 85% coverage of the sun. [3]
How to view it for yourself
It’s essential to protect your eyes while observing the eclipse; looking directly at the Sun without the right protection can cause serious damage to your eyes.
The below video from NASA [4] demonstrates some safe viewing methods:
Don't forget to keep an eye on the weather forecast too – it's a good idea to be ready to move to another location in case the weather turns cloudy where you are.
Eclipse Glasses
Specialised glasses, such as Baader AstroSolar eclipse glasses, are designed for safe solar viewing. These glasses block the majority of light, allowing you to see the eclipse clearly.
It's important that the eclipse glasses (or filter) you choose conforms to the ISO standard 12312-2:2015, the internationally-recognised solar viewer transmission requirements for eye safety.
Baader AstroSolar eclipse glasses (which meet this ISO standard) are available to purchase on the Astro Printer shop.
Pinhole Projector
A pinhole viewer is a simple way to project the eclipse onto a surface. You can make one using a piece of cardboard with a small hole, allowing sunlight to pass through to project an image of the eclipse on the ground or a piece of paper. It's important the the hole is small (literally a pinhole) for this method to work.
This video from Veritasium [5] shows an example of pinhole projectors in use. Interestingly, it demonstrates that the shape of the hole isn't actually too important - as long as it's a small hole.
Binoculars or Telescope with a Solar Filter
If you have binoculars or a telescope you'll be able to get a closer view of the eclipse, but it's important you use an appropriate solar filter to protect both your eyes and equipment. Simply wearing eclipse glasses is not enough!
A solar filter should be mounted at the front of your telescope (or binoculars). Otherwise, the sunlight hitting the mirrors or lenses inside your equipment will be focussed into an intense beam that could damage the optical assembly as well as your eyes.
It's important that the solar filter is securely mounted with no gaps and there is no damage to the filter film – even a small hole would be dangerous.
With a telescope you can either view the eclipse directly, or project a magnified image of the eclipse from the telescope onto a surface, so that multiple people can view it. An example of this projection method is shown in the above video by NASA.
For more detailed advice on viewing the eclipse with a telescope, references [6], [7] and [8] below are useful.
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However you choose to observe it, enjoy the eclipse!
Credits / Useful Links
For further advice on telescope filters:
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