如今任一时刻在太空中的人数约为10人——国际空间站7人，中国“天宫”3人，比例为7:3。杰夫·贝索斯预计该数字将在未来几十年提升五个数量级至约1,000,000人，相当于从当前水平增加100,000倍。

埃隆·马斯克也谈到火星可能出现类似规模的定居人数，而中美两国都表示希望建立永久月球基地；一份于2025年末发布的美国国家科学院报告称，如果人类加入目前由机器人承担的任务，火星探索将更出色。可重复使用火箭（如SpaceX的Starship与蓝色起源的New Glenn）正在加速抵达轨道，但要支撑更大规模人群，必须依赖能够循环食物、氧气与废弃物的封闭生态系统，而非仅对约10人尚可的补给与丢弃。

由于生态系统研发远落后于火箭技术，长期扩张仍受约束，而“地球化”设想也带来伦理与科学风险，包括可能伤害任何脆弱的火星微生物。行星保护规则把最可能宜居的火星区域对人类与机器人都划为禁区，这既让探测更困难，也引发了要求在严格污染限制与可执行监管下进行谨慎放松管制的呼声。

Today about 10 people are in space at once—7 on the ISS and 3 on China’s Tiangong, a 7:3 split. Jeff Bezos projects a rise by five orders of magnitude to roughly 1,000,000 people, implying a 100,000× increase from current levels.

Elon Musk cites similar settlement-scale numbers for Mars, and governments in China and the United States state goals of permanent Moon bases; a late-2025 National Academies report argues Mars exploration would improve if humans joined the robots. Reusable rockets such as SpaceX’s Starship and Blue Origin’s New Glenn are accelerating access, but sustaining larger populations requires closed ecosystems that recycle food, oxygen, and waste rather than resupply and disposal that suffice for only ~10 people.

Because ecosystem science lags behind rocketry, long-duration expansion remains constrained, while proposed terraforming raises ethical and scientific risk, including the possibility of harming any fragile Martian microbes. Planetary-protection rules keep the most habitable-looking Martian regions off-limits to humans and robots, prompting calls for carefully deregulated investigation paired with strict contamination limits and enforceable oversight.

Source: The future of space exploration depends on better biology

Subtitle: Rockets are great, but sewage treatment is what you need for the long haul

Dateline: 12月 31, 2025 02:46 上午