Mauna Kea in Hawaii is the world’s tallest mountain — about 1000 m taller than Mount Everest (Science, volume 313, 22 September 2006, p. 1732). Near the summit, at an altitude of 4092 m, is the James Clerk Maxwell Telescope (JCMT) — the largest astronomical telescope designed to operate in the sub-millimetre wavelength region of the spectrum. In 1987 the JCMT was dedicated by HRH Prince Philip, Duke of Edinburgh, and named for the physicist James Clerk Maxwell (1831-1879). Sir John Dutton Clerk of Penicuik Bt, CBE, VRD, DL FRSE (1917-2002) represented the family.