Fun With Science / Dome Review / Eclipse 2026
The geometry of the shadow, and where it falls — Greenland, Iceland, Spain.
On 12 August 2026 the Moon's shadow sweeps from the Arctic down across Greenland, Iceland and northern Spain. The remarkable part isn't the eclipse itself — it's that the path below was worked out decades ago from three bodies, an inverse-square law and a sphere spinning under its own shadow. The map is a prediction, printed years before the event, accurate to the second and the kilometre. Below: the geometry that produces it, then the track it draws on the Earth.
Drag to orbit. The Sun lights one hemisphere; the Moon, nearly in line, drops a small dark umbra onto the day side. Where that umbral spot touches the surface, the Sun is totally eclipsed. Scrub the timeline to walk the spot along its track over the roughly two hours of the event.
Sizes and distances are compressed so the alignment is visible in one frame; the real Sun is ~400× the Moon's diameter and ~390× further away, which is exactly why the two discs appear nearly equal from Earth and totality is possible at all.
The track begins at sunrise over the Russian Arctic, passes within ~100 km of the North Pole, then curves down the globe: across Greenland's Scoresby Sund, over western Iceland, out across the North Atlantic (where the eclipse is deepest), and into northern Spain at sunset — the Sun only a few degrees above the horizon over the Ebro valley and the Balearic Sea.
Central line interpolated from NASA/ESA published path data; totality is a band roughly 100–300 km wide about this line. For your exact local times, the interactive maps at NASA and timeanddate (linked below) are authoritative.
London and the rest of the UK see a partial eclipse, not totality: about 91% of the Sun covered at maximum (19:13 BST), with the eclipse running from ~18:17 to ~20:06 BST — low in the northwest evening sky. Worth eye protection and a clear horizon; not worth expecting darkness.
Circumstances and path data: NASA — 12 Aug 2026 total solar eclipse · ESA global map · NASA GSFC eclipse office. Interactive local-time viewers (further viewing): timeanddate. Coastlines: Natural Earth via world-atlas.