Now that the International Space Station is functional, it's feasible to assemble exploration systems in low earth orbit from multiple Falcon launches, and even use another unladen (except for fuel) Falcon Heavy to tow those packages out to lunar orbit before final assembly, testing and launch.
That allows for such luxuries as safely sending protected components of a nuclear power plant to lunar orbit before final assembly and activation, and once there it can't come back down unless you want it to. It's even feasible to send the International Space Station
itself out as a
manned planetary exploration vehicle, with Falcons providing periodic supply rendezvous. That's the way humans should have been exploring space from the beginning.
Once you've reached lunar orbit, as Arthur C. Clarke pointed out half a century ago, you've already expended over 90% of the energy needed to reach Saturn from Earth, meaning that all of the solar system--all of it!--is open to exploration, cheaply, reliably, and with the critical input of actual humans. We could see it all coming together in less than twenty years.