Challenges and Prospects of Solar System Colonization: Beyond Fusion Propulsion

Is the development of fusion propulsion critical for the colonization of the solar system? While ambitious, fusion propulsion may not be necessary considering the advancements in existing technologies. This article explores the current state of interplanetary travel and discusses why colonization of the solar system remains both feasible and practical with current technologies.

Current Technological Capabilities

Technological advancements have already brought us closer to the colonization of part of the solar system. Companies like SpaceX have made significant strides with their Starship program, and traditional nuclear engines offer viable alternatives for robust interplanetary transport. The focus should be on addressing other critical challenges, such as life support, rather than pursuing fusion propulsion.

Interplanetary Transport: Nuclear Pulses and Beyond

No new propulsion systems need to be invented for rapid and reliable transport within the solar system. One established method is the Old Bang-bang approach, specifically nuclear pulse propulsion, or Project Orion. This involves using fission A-bombs to propel a spacecraft into the cosmos.

The design concept includes sectional ships lifted into orbit and assembled before being fueled. A series of three to five Saturn-V boosters can place the spacecraft into orbit. Indeed, the SpaceX Starship (BFR) could also be used for similar missions. A cargo ship might take longer with a Hohmann transfer, but around 85% of its payload would be reserved for Mars orbit. When Earth and Mars are at their closest points, a crewed ship can "jump" to Mars in just 21 days, reaching cometary speeds of approximately 21 days for the journey.

Exploring asteroids, moons, or Trojans of Jupiter presents a much shorter travel time, with several months being sufficient. However, the most challenging technical aspect of nuclear pulse propulsion is the repetition of the pulse process. One needs to toss a 3/4-ton keg aft at several hundred m/s every 20 seconds, while spraying a grease mist over the pusher plate between pulses.

Risk and Priorities

The prioritization of life support over propulsion is crucial for the immediate future of interplanetary travel. Atmospheric interactions and landing scenarios are complex problems that current single-use, single-purpose vehicles cannot adequately address. Until these issues are resolved, low Earth orbit (LEO) or the Earth-Moon Lagrange points might serve as the ideal limit for exploration.

Atmospheric stations like those in the Antarctic or CFS Alert require continuous support due to harsh conditions. These settings are not easily compared to the vacuum of space. Living in Antarctica or other remote locations is much more tolerable due to the presence of gravity and the ability to sustain life within a controlled environment.

Historical Precedents

Previous attempts at colonial expansions, such as the early North American colonies and the Viking settlements in Greenland and Newfoundland, highlight the importance of environmental factors and supply lines. The success of these efforts depended on the availability of resources, support networks, and the ability to sustain life in challenging environments.

Living in space, around a 500-foot depth, poses unique challenges that are not easily compared to a terrestrial environment. The transition to space living is significantly more difficult due to the lack of gravity, supply constraints, and life-support systems.

As highlighted by astronaut Buzz Aldrin, the current state of interplanetary exploration is far from ideal. Simply sending a capsule with food and three individuals results in a significant reduction in mass and functionality upon return. This underscores the need to focus on practical, immediate solutions before pursuing grand ambitions.

In summary, while advancements in technology are exciting, the focus should remain on solving current challenges to achieve sustainable and practical space colonization. Fusion propulsion may be a future goal, but the more pressing issues of life support and reliable transportation methods must be addressed first.