Final answer:
Captain John Black and the Expedition discovered the chilling theory that Mars is much less amenable to colonization than previously believed, due to its inhospitable environment. This reflects the idea that while human nature drives us to explore, such journeys do not always result in new settlements.
Step-by-step explanation:
In discussing the chilling theory surrounding Mars encountered by Captain John Black and the Expedition, it's clear that they discovered that Mars is not as hospitable or promising for colonization as once thought. This realization dawned upon them as sobering truths about the Martian environment became apparent—harsh atmospheric conditions, barren landscapes, and the lack of immediate resources for human survival. It reflects a broader theme of exploration, where the romanticized version of finding new worlds akin to the voyages on Earth contrasts with the stark reality of space exploration that is more akin to scaling the perilous heights of Mt. Everest. The message here is that while exploration is in our nature, it is necessary to manage expectations and acknowledge that not all exploration leads to settlement, and that space, as depicted in entertainment, is not always reflective of truth.