Last June, Nasa and the Japanese Ministry of Economy, Trade and Industry published a detailed topographic map of the Earth, covering an unprecedented 99 per cent of the planet's landmass. The map was compiled from data collected from a Japanese radiometer on board an American spacecraft; the elevation measurement points are only 30 metres apart. According to Nasa, the data 'fill in many of the voids ... such as in very steep terrains and in some deserts'. Anyone can look at it online for free. It would seem that now there really is no uncharted territory left on the surface of the Earth. If you wanted to set out exploring unknown terrain with a map that could still even half-plausibly claim 'here be dragons,' you'd have to go deep underwater, deep underground or into deep space.

LRB 27 May 2010 | PDF Download