Nuclear Pulse Propulsion and Beyond:
Best Method to Go Interstellar Using Current Science (and Engineering)

Current science isn’t enough to launch humanity to the stars; you need current engineering in order to be able to actually build the ship.

Anti-matter is theoretically possible, but we are nowhere near engineering the containment systems that would be necessary even if we had a ready source of the anti-material.  Then there comes the problem of really getting propulsion from a pure energy source.

Fusion energy has been “25 years away” for the past twenty-five years.  In other words, we haven’t solved the containment problems here on earth, let alone for the scale required in space for propulsion.

Solar sail propulsion runs into the materials engineering side of the interstellar propulsion selection problem.  For sails of the magnitude of the ones necessary to pull an interstellar craft capable of surviving with passengers a decade or two in space to the nearest stars, the tensile strength and longevity of the sail material (which must be very, very light) and cables is perhaps something we could engineer right now, but we don’t have enough experience with these materials for long term service in interstellar conditions.  We would also have to solve the inevitable maintenance problem of how to fix sails in-flight.

Of the choices given, the nuclear pulse propulsion option is the one with most of the engineering problems already “solved.”  We know how to make workable bombs, to make ablative and high-temperature materials for the blast shield, and how to shield against harmful radiation of all types (alpha, beta, gamma and neutron).

What bothers me is the exclusion of two other types of propulsion that have been already engineered and would be available for long-term flights without so much waste of fissionable material—nuclear rocket engines (NERVA) and ionic propulsion powered by nuclear-generated electricity.  With an abundance of available boost-mass (water), a nuclear-reactor propulsion system could be much more cost-effective, less polluting, and have the benefit of solving the on-board power problems for decades-long trips as well.

Nuclear power systems have already been used successfully in space for many space missions, and they have proven safe and reliable to provide power for multi-year missions, beyond the range of usable solar powered systems.

The bottom line is that you have to be able to engineer the systems currently, not just have the theory current.  It will be the engineers that take humanity to the stars.

“Engineers, taking dreams and making them nightmares, taking nightmares and making them reality” —Chuck Ballard, PE

Chuck Ballard will receive a copy of Going Interstellar signed by editor Les Johnson and five free ebooks from Baenebooks.com.