Andrew Knoll, professor of natural history and earth and planetary sciences at Harvard University delivered a lecture at Lehigh University last Monday in which he made very positive statements in favour of past life on Mars. Knoll and his team at Harvard were actively involved in the 2004 missions, which landed the Spirit and Opportunity rovers (now in their second year of exploration) on Mars. One attendee was less than overwhelmed by Knoll's conclusions, (see more at the Lehigh student newspaper) but I was personally struck by his evocative use of the word "canals". Obviously Knoll is not proposing anything like the canals made fashionable a hundred years ago by Percival Lowell, but it is kind of touching to see the word appear in a scientific discourse. Lowell would be delighted.