2. Long-distance Avoidance Plan: extremely low feasibility. This plan would involve constructing a human habitat at sufficient distance from the Sun to avoid its explosive destructive power. Based on the model and projected development of engineering techniques for hardening space cities in the foreseeable future, the minimum safe distance would be sixty AU from the Sun, which is beyond the Kuiper Belt. At that distance, few resources would be available in space for constructing a space city. Similarly, the lack of resources meant that even if such a city were built, it would be almost impossible to maintain for human occupation.
V. The Bunker Project: the four gas giants could be used as barriers to avoid the solar explosion from a dark forest strike. In the shade of the four planets, away from the sun, sufficient space habitats would be constructed to house the entirety of the human population. These space cities would be located next to the planets, but would not be their satellites. Instead, they would orbit the Sun in synchrony with the planets, staying within their shadows. The plan called for a total of fifty space cities, each of which was capable of housing about fifteen million individuals. Specifically, twenty cities would be shielded by Jupiter, twenty by Saturn, six by Uranus, and four by Neptune.
VI. Technical challenges facing the Bunker Project: The technology required by this plan had all been mastered by humanity. Fleet International possessed extensive experience constructing space cities, and there was already a sizable base around Jupiter. There were some technical challenges that could be overcome within the required timeframe, such as how to regulate the positions of the space cities. Since the space cities would not be satellites of the gas giants, but would have to stay in close proximity of the planets, they would fall toward the planets, unless propulsion systems were installed to counteract gravity and maintain their distance from them. Initially, the plan called for the space cities to be positioned at the L2 Lagrangian points, such that the space cities’ orbital periods would match their respective gas giants’ without needing to expend much energy. However, it was later discovered that the L2 Lagrangian points would be too far away from the gas giants to provide sufficient protection.
VII. The survival of the human race in the Solar System after a dark forest strike: After the destruction of the Sun, the space cities would rely on nuclear fusion as their energy source. By then, the Solar System would appear as a spiral nebula, and the scattered solar material would provide an inexhaustible supply of easily collectable fusion material. It should also be possible to gather more fusion fuel from the remaining core of the Sun, sufficient to ensure humanity’s long-term energy needs. Every space city could be equipped with its own artificial sun that would generate an amount of energy equivalent to the amount that had reached the surface of the Earth before the strike. From an energy efficiency point of view, the energy supply available to humans would actually be orders of magnitude higher than the pre-strike period because the space cities would consume fusion fuel at only one-billion-billionth the rate of the Sun. In that sense, the extinction of the Sun would be an improvement, because it would stop the extremely wasteful consumption of fusion material in the Solar System.
Once the nebula had stabilized somewhat after the dark forest strike, all the space cities could leave their barrier planets and find more suitable locations within the Solar System. It might be advisable for them to depart from the ecliptic plane so that they could avoid disturbance from the nebula while being able to dip into it for resources. Since the solar explosion would destroy the terrestrial planets, the mineral resources of the Solar System would be scattered in the nebula, making them easier to collect. This would make it possible for more space cities to be constructed. The only projected resource limitation on the number of space cities was water, but there was a 160-kilometer-deep ocean covering Europa, providing a source of water greater in volume than the Earth’s oceans, and capable of supplying a thousand space cities with individual populations ranging from ten to twenty million. More water could also be obtained from the nebula itself.
Thus, the post-strike Solar System nebula was capable of supporting over ten billion people in comfort, leaving human civilization plenty of room for development.
