People across Northern Ireland will have the opportunity to see a deep partial solar eclipse on Wednesday evening, when the Moon passes between Earth and the Sun. Belfast will remain outside the path of totality, but calculations indicate that most of the solar disc will be covered at the height of the event.
The partial eclipse is expected to begin in Belfast at about 6.10pm. Maximum coverage is calculated for 7.08pm, with an eclipse magnitude of 0.938, before the event ends shortly after 8pm. The precise view will depend on local cloud and an unobstructed outlook towards the western sky.
The same eclipse will be total along a narrower track crossing Greenland, Iceland, northern Russia, the Atlantic and parts of Spain and Portugal. Northern Ireland lies outside that track, so the Sun will not be completely hidden at any point when viewed locally.
Safe eye protection is essential throughout a partial eclipse. Ordinary sunglasses are not suitable. Solar viewing glasses or handheld filters should comply with the ISO 12312-2 standard, while cameras, telescopes and binoculars need a purpose-made filter fixed to the front of the equipment.
An indirect view can be made with a pinhole projector, which casts an image of the Sun onto a separate surface. The viewer should keep their back to the Sun and look only at the projected image. Looking through the pinhole itself is not safe.
NASA advises that direct viewing without protection is safe only during the brief total phase experienced within the path of totality. As Belfast will see a partial eclipse for the entire event, suitable protection must remain in place whenever anyone looks towards the Sun.