It was a short leap from that observation to the idea that Europa's icy surface was hiding a giant ocean. Europa was suddenly the most exciting body in our solar system, because with liquid water came the possibility that life could exist in our solar system. If these were introduced into the Europan ocean then NASA would have seeded Europa with life, and at the same time have made it impossible to distinguish distinctively Europan life. While Frank and his colleagues were contemplating the enormous challenge, the discovery of Lake Vostok came to their attention. It gave them an idea.
Timing is everything.
Lake Vostok would be the perfect testing ground for a mission to Europa. It was an idea that made many people uneasy. They feared that NASA would be prepared to sacrifice Vostok in order to perfect their Europa mission. Environmental lawyer Jim Barnes, who successfully campaigned against mining in Antarctica, argued that NASA s proposed timetable to explore Lake Vostok was driven entirely by the needs of their Europa mission. Lying four kilometers under the Antarctic ice, the pristine waters of Lake Vostok could contain hitherto unencountered life forms.