Frequently Asked Questions
Which web browsers are able to display the maps?
Our maps are displayed using a 3D graphics library called WebGL. Most modern web browsers support it, but some mobile devices or older browsers may not. The following browsers support WebGL:
- Chrome 8+
- Firefox 4+
- Opera 12+
- Safari 5.1+
- Internet Explorer 11+
- Edge 12+
Why do some low-lying areas appear as sea?
Our maps are based on topographic data collected from NASA's Shuttle Radar Topography Mission (SRTM) in 2000. While making these maps, NASA's Space Shuttle flew over the Earth, using radar to measure the height of the terrain below.
Unfortunately the radar wasn't able to distinguish water from sea, and so it is not always possible to distinguish low-lying land, such as most of Holland, from sea. Likewise, lakes above sea level generally appear as land.
Why are the maps blank north of 60°N and south of 60°S?
When the Space Shuttle flew made the maps we use, it flew over all latitudes between 60°S and 60°N. The particular orbit that the Shuttle was in meant that it never flew over the north and south polar regions, and so no data is available there.