An Ocean of Stars - for those of us driven to explore space, the Earth’s ocean should seem a close cousin. In fact, so many aspects of ocean exploration are similar to the challenges of space, that some people have suggested our own oceans are the true final frontier. There are certainly still more accessible than the reaches of outer space, and even a modestly deep scuba dive can give you a vivid impression of what it may feel like to float in the blackness of space.
Want a fallback plan for when that final environmental catastrophe occurs? Underwater or floating habitats may offer fewer challenges than space colonies if you’re looking to quickly build a self-sustaining place to live when things cool down, warm up, dry out, or otherwise return to fitness for human habitation.
If you’re just looking for wide open spaces, the vastness of space may ultimately prove your final frontier, but Söhnlein has a very human take on the question: “For myself,” he says, “I’d probably go with the oceans. Humanity has millennia to explore the cosmos. But I have only decades or—depending on who you believe—centuries. And there’s plenty to discover down there to fill my lifetime.”