NTR is not competitive with chemical rockets in any actual application. Dry mass has to triple at a minimum, your propellant evaporates over long trips, and NTR engines don’t have enough thrust to land on Mars or even the moon, requiring the additional dry mass and complications of specialized landers.
We need a huge step forward in NTR before it’s going to be useful at all.
Those already take the slow boat Hohmann transfer orbit to maximize payload capacity. Starship might be able to send 150 tons that way to the surface itself. And building bigger starships is easier than building NTRs.
We need a huge step forward in NTR before it’s going to be useful at all.