“It’s interesting. Before satellite AIS came along, you’d talk to people and they’d just assume that ships were tracked wherever they went in the world. But the reality was that there were 60,000 ships out there carrying nine trillion dollars’ worth of cargo, and when the captain went over the horizon, unless he sent a signal, no-one knew where he went. That’s all changed now,” says ExactEarth’s John Allan.
(via BBC News - Ahoy! Your ship is being tracked from orbit)