The Space Launch System and the Copernican Principle

There has been a trifecta of very recent news regarding the Space Launch System, which I almost missed given the frenetic activity associated with North Korea’s strategic nuclear programmes.

NASA reports that a full scale model of the core of the Space Launch System, key to a future manned Mars mission, known as the Core Pathfinder, will soon be delivered to it by a contractor. Late in August NASA also completed static hot fire ground tests of the controller on the RS-25 engine, a cluster of four of which will feature on the SLS first stage, and NASA also just announced completion of testing of the SLS Block 1 and 1B Solid Rocket Booster avionics.

The full scale model of the SLS core stage, that is the Core Pathfinder, will be used to practice handling and transportation of the core stage prior to doing so with the real thing. It’s interesting to read, in the above linked report, that the smallest part of the Core Pathfinder, the lock on fittings for the SRBs, is the most expensive.

The RS-25 controller is essential for controlling the flow rate of propellants to the RS-25 combustion chamber and so thereby managing the thrust of the engine. The SRB avionics plays a similar role, although of course the SRB boosters are solid fuelled. The RS-25 was the Space Shuttle Main Engine, however the controller on the RS-25 for the SLS is more efficient. The SRB for the Block I and Block 1B variant of the SLS are derived from the Space Shuttle’s SRBs, but the final Block 2 will use more advanced boosters than the Shuttle SRB.

Here’s a cool video of a test of the SLS SRB. Bang!!!

The SLS is controversial, mainly on two grounds. Firstly, it is argued that a cheaper more efficient heavy lift space launch vehicle than the SLS could have been developed. Secondly, and more fundamentally, it is argued that a manned mission to Mars will add little of real value to space exploration and that it would be better to devote available funds to exploration of the solar system, especially exploration of the moons of Jupiter and Saturn which hold much more scientific promise.

Multiple news on the SLS front got me thinking about the very concept of space exploration, given the controversy associated with the SLS. It seems to me that space exploration is all about putting the Copernican Principle to the experimental test. How uniform are planetary dynamics, that is can we develop a general theory of planetary systems that includes geology as a subset? Are there other life forms, how uniform if so, and is there a general theory of evolution? Are there any forms of extra-terrestrial intelligence, and what might that say about higher order cognitive systems more broadly? Such questions are the essence of space exploration, and when you think about the matter a tad it all seems to come back to the Copernican Principle.

Personally, I think this is well worth doing and well worth the investment. Space exploration takes many forms; one can argue that terrestrial astronomy is a form of space exploration on the same continuum as space flight. Space exploration, for genuinely scientific purposes, is one of our grandest ventures, surely on a par with anything flying out of particle collisions at CERN.

That being the case, what would be of more value regarding empirical testing of the Copernican Principle? A manned mission to Mars or further exploration of the Solar System?

I’m kind of thinking the latter.