Startup to watch: Atomos Space wants nuclear power reactors up and running in space for orbital transportation.

• The Denver-based startup, launched in 2017, is navigating complicated US government regulations to test a low-power nuclear fission reactor called the Neutrino Space Nuclear Pathfinder in orbit, per Vice.
• The Neutrino mission is part of a larger effort to provide “space tug” services to guide satellites to their destination orbits post-launch, which is currently hindered by energy supply constraints in space.
• Atomos’ nuclear transit tech would also provide satellite recovery, relocation, disposal, life extension services, and space logistics services, according to the company’s website.
• SpaceNukes and X-energy, along with NASA and DARPA, are also working to develop space nuclear reactors.

How we got here: Fears over nuclear weapons deployed in space and the concern about nuclear’s safety have foiled decades worth of planning to use the energy source for orbital activities. However, the private space industry’s rise and approaching plans for longer-duration space travel have spurred demand for energy solutions.

• The only nuclear fission reactor the US ever sent into space was in 1965.
• In the 1980s, the Soviet Union’s nuclear space reactor contaminated Northern Canada with radioactive debris, likely fueling concerns that stalled plans in the US.
• But in December 2020, the Trump administration issued a National Strategy for Space Nuclear Power and Propulsion, clarifying rules for the technology and paving the way for companies like Atomos Space.
• A statement from Atomos’ main investor, Cantos Ventures, claims that current last-mile satellite delivery is very slow due to energy limitations, and that nuclear propulsion will be needed for humans to become a multi-planetary species.
• “Current propulsion technologies are evolutionary dead ends and can’t scale into the future space economy,” said Atomos Space CEO Vanessa Clark, per Space News.

The opportunity: Space nuclear reactors may be one of the easier ways to generate energy in space compared with the technical hurdles of space-based solar arrays.

• Reliable power for space activities could be the key to accelerating progress in satellite recovery and space exploration.
• With Earth’s orbit becoming increasingly crowded, nuclear propulsion could help prevent collisions that cause space debris.

A longstanding problem: In addition to the risk of accidents, nuclear fission reactors have an inherent problem with waste.

• Although the radioactivity is considerably less with low-enriched uranium, the problem of what to do with the spent fuel in space remains.
• Avalanche Energy Designs is working on it, but more investment is needed in nuclear fusion space reactors to solve the waste problem.
• Plasma, which is abundant in space, holds promise for both nuclear fusion and rocket propulsion and could enhance the power and efficiency of space travel.