On 29 March 2025, the Moon will pass across the disc of the Sun to cause a partial solar eclipse visible from the UK.
The event begins with first contact at 10:07 UT (time for the centre of the UK; timings vary by location), when the Moon’s leading edge first makes contact with the edge of the Sun.
After this, an ever-increasing bite appears to be taken out of the Sun’s disc until the point of greatest eclipse at 11:05 UT.
What's more, this partial solar eclipse takes place late on a Saturday morning, making it rather conveniently timed for most of us.
Partial solar eclipse explained
During a total solar eclipse, the Moon passes between Earth and the Sun and blocks out the Sun entirely, plunging the area from which it's observed into quiet darkness.
A partial solar eclipse means that only a portion of the Sun is covered by the Moon. It looks as tough the Moon's silhouette is taking a bite out of the solar disk.
When a total solar eclipse reaches 'totality', the point at which the entirety of the Sun is covered by the Moon, it's possible to view with the naked eye.
But during the phases leading up to and after totality, eclipse glasses must be worn.
For a partial solar eclipse, eclipse glasses (or solar filters or solar telescopes for that matter) must be worn for the duration, as not doing so could damage your eyesight.
Find out more via the American Astronomical Society's top tips for choosing safe eclipse glasses.
Best places to see the 29 March partial solar eclipse
The whole of the 29 March partial solar eclipse occurs at an altitude over 34°, making it well placed for UK viewing.
The best place to see it will be the northwest of Scotland, where 47.8% of the Sun will be covered by the Moon.
The southeast of England gets the smallest eclipse, with only 28.1% of the Sun hidden by the Moon.
How to observe the eclipse
Although it doesn’t match a total solar eclipse, a partial eclipse of the Sun is still amazing to observe and there are many ways to do this safely.
If you plan to view or image the event through a telescope, you need to take full solar precautions and a full-aperture certified solar safety filter is advised.
Another safe method for observing the eclipse is to use a piece of white card as a screen and another piece of card for solar projection.
A 1–2mm hole created in the projection card allows the Sun’s light to pass through, projecting a pinhole image onto the screen card.
The projected image is a small but perfectly formed representation of the eclipse.
For those with hydrogen-alpha solar viewing kit (note, not hydrogen-alpha deep-sky filters, which are not suitable), the eclipse progress is given an interesting boost as there are many more light and dark features visible within the Sun’s chromosphere to use as a gauge for how the Moon is progressing.
In addition, seeing the sharp profile of the Moon’s edge cutting across any visible prominences is a stirring sight.
The current solar cycle is expected to peak in 2025, making it highly likely that the Sun’s disc will have lots of interest on it whether in hydrogen-alpha, another narrowband wavelength or white light.
Find out more about these filters in our guide on how to photograph solar activity.
Sunspots or equivalent features provide a useful backdrop that allows you to visualise the Moon’s motion in its orbit.
Find out more in our guide on how to observe a solar eclipse.
If you observe or photograph the 29 March 2025 partial solar eclipse, get in touch via contactus@skyatnightmagazine.com
