In September 2022, a spacecraft struck a small asteroid moonlet about seven million miles from Earth. The collision changed its orbital period by thirty-three minutes. DART was a controlled test against an object that posed no threat, and it demonstrated that human beings can alter the path of a celestial body before it reaches us.
NASA’s analysis of DART is a compact answer to the idea that humanity is only a burden on the planet. Nature produced the hazard. Human observation found it, and human engineering developed a possible defense. We can damage the world badly. We are also the only known creatures capable of noticing a threat decades away and deciding to protect every species in its path.
More eyes on the problem
Planetary defense starts with telescopes finding an object early enough for a small deflection to work. DART’s result was measured through an international observing campaign. The defense depends on scientists and equipment maintained between rare emergencies.
A larger population can support more of that web if it is prosperous and well educated. It can afford people whose daily work appears unnecessary until a strange orbit is detected. Growth gives no guarantee of wisdom; more people can create larger harms too. The asset is human capacity joined to institutions capable of correction and cooperation.
The same capacity addresses environmental strain. A crowded, wealthy world may consume more, and the physical costs are real. It also has stronger incentives to produce food with less land and recover scarce material instead of discarding it. Closed-loop water and air systems developed for space can return to Earth. The relationship can run in both directions: protecting a settlement teaches us how to use this planet more carefully.
A second branch
Settlement beyond Earth eventually adds a different kind of resilience. Two self-sustaining populations would face different local dangers. A catastrophe on one world could leave the other alive. At first the connection would remain a strength, allowing knowledge and material to move between them. Over time each branch could preserve what the other lost.
Distance also creates new risks. A settlement can become hostile, and its rulers may use control of transport or life support cruelly. Independence leaves liberty uncertain. Multiple communities with different sponsors may offer better chances for experimentation and escape than one centrally designed colony, though the early economics may push toward concentration.
This is another reason population depth matters. Redundancy is expensive. A civilization barely maintaining one technical base will optimize it tightly and fear alternatives. A growing civilization has more room for two designs, including the odd one that survives when the favored design fails.
The planetary asset is another generation capable of learning what DART’s builders learned, then applying it to a danger they cannot yet name. Fewer people can be exceptionally capable. More capable people give Earth more chances.
Citations
- NASA, “NASA’s DART Data Validates Kinetic Impact as Planetary Defense Method”, 2023.
- NASA, Planetary Defense Strategy and Action Plan, 2023.
- NASA, “Human Spaceflight Technologies Benefitting Earth”, 2022.