A 3D model of Vesuvius, Monte Somma and the plain to the east, made from satellite images and elevation data. When the eruption plays, lava flows spread north towards San Sebastiano and south-east, lava fountains rise from the crater, and an ash column drifts east and then south-west. The panel describes each stage in words as it happens.
Vesuvius, March 1944
Evidence from 1944 archive
How this works
Where the lava goes comes from the same method as the Vesuvius lava page (DOWNFLOW, Favalli and colleagues 2005), run on today's ground for the two 1944 flows: north (stopping at about 140 m above sea level) and south-east (about 350 m). Lava is drawn where at least 1 in 5 of the simulated flows went.
When it gets there is an estimate. The lava moves at a steady speed, set so that the northern flow reaches San Sebastiano early on 21 March, as recorded. The real speed varied from 50 to 300 m an hour. The colours show lava cooling from yellow-hot to a dark crust, and are for illustration.
The eruption column follows INGV's account: lava fountains throwing material up to about 4 km (21–22 March), then explosions with a column more than 5 km high (22–23 March). Studies estimate over 10 km at the peak. The wind carried ash 15–20 km east. Smaller explosions blew ash to the south-west until 29 March. The particles, fountain height and the shape of the grey ash on the ground are illustrations that follow those directions and distances.
Standing in a town shows the same model at real size, with heights not exaggerated. You start at eye level in the town and can move anywhere, as on the table. Go more than about 2 km up and the daylight sky fades to the dark table background. Close to you the ground is drawn in 10 m steps with sharper satellite images, but the elevation data is about 30 m, so small bumps and buildings are missing. The lava is drawn 5 m thick, an estimate from the 10 million m³ of lava recorded for 1944 spread over the model's flows. Standing in a town only changes your view: the eruption carries on from the same moment, at the same pace as on the table, so the lava front moves much faster than it really did. The falling ash is an illustration.
Town labels are placed approximately. On the table, heights are exaggerated 1.5 times, and the column is drawn to the same scale.
Sources: INGV Osservatorio Vesuviano (opens in a new tab) · Geological Magazine reconstruction (opens in a new tab) · 1944 lava flow map (Journal of Maps) (opens in a new tab, PDF)
Versions
| Part | Version | What it is |
|---|---|---|
| App | VR 0.15 | 0.15: sound on iPhone: the audio is started properly inside the tap, and a silent track loops while the eruption plays so the ring/silent switch does not mute it. 0.14: on a phone the sheet is smaller: closed, it shows the controls with the date and the stage on one line, and the commentary is under More; eyewitness cards are off by default (turn them on under Evidence from 1944) and smaller when on; smaller credits. 0.13: works on a phone held upright: the panel becomes a sheet along the bottom with the model above it, "More" opens the rest of the controls, the AR button sits in the sheet, bigger touch targets, and the credits move to the top right. 0.12: credits shortened to one line with a Sources list (exact data credits, “Powered by Esri”); © line removed; height note moved to the headset menu. 0.11: in a town, going more than about 2 km up fades the daylight sky and haze to the dark table background. 0.10: when the eruption ends, the last ash drifts away and settles instead of stopping in mid-air. 0.9: in a town you are no longer fixed to one spot: the mouse, wheel and keys work as on the table, starting at eye level, never below the ground. 0.8: in a town, the scroll wheel and + / − zoom in like binoculars, and right-drag looks around (both did nothing there). 0.7: standing in a town only changes the view; the eruption carries on from the same moment at the same pace (it used to jump to just before the lava or ash arrived and slow to 3 minutes a second). 0.6: accessibility (keyboard control of the model, screen-reader descriptions and announcements, contrast, focus outlines, all sections available on small screens and when zoomed) and credit tag. 0.5: link to the step-by-step VR story. 0.4: adds the 1944 archive (newsreels, photos, eyewitness accounts, historian tasks) and eyewitness accounts on screen and on the headset menu as the eruption plays |
| 1944 archive | – | Shared file from jsawle/curriculum_artifacts (vesuvius-1944-archive.js), also used by the lava explorer and the 3D eruption page |