How will we adapt to interstellar travel? Rocket Pioneer, Robert Goddard, speculated on interstellar travel back in 1918. He saw two options – if we can release atomic energy then asteroids or small moons could be used as large starships travelling at reasonable speeds. Alternatively, if atomic energy proved impossible, he pondered…
[...]will it be possible to reduce the protoplasm in the human body to the granular state, so that it can withstand the intense cold of interstellar space? It would probably be necessary to dessicate the body, more or less, before this state could be produced. Awakening may have to be done very slowly. It might be necessary to have people evolve, through a number of generations, for this purpose.
In the latter case he suggested solar-boosted hydrogen/oxygen rockets, with interstellar speeds of just ~5-15 km/s. That’s 60,000-20,000 years per light-year. The pilot would need to ‘wake’ occasionally for course corrections – though Goddard had suggested an automatic navigation system back in 1907-1909 using photo-cells, a system used on the “Mariner” probes – so would be re-animated every 10,000 years on trips to nearby stars, and every 1,000,000 years or so, for longer trips.
Goddard had worked on solar-powered ion rockets back in 1909. But he didn’t consider light’s own pressure to push solar-sails. If he had, then the 1,000 year missions to Alpha Centauri suggested by Greg Matloff would’ve seemed a natural improvement over the deca-millennial missions chemical rockets implied.
Of course we know atomic energy can be harnessed – if we so dare. Yet the idea of flying between the stars as mummified cryogenic life-forms has a strange allure. To travel the stars so, we would needs become like human-sized ‘tardigrades’ or ‘brine-shrimp’, both of which can undergo reversible cryptobiosis in a mostly dessicated state. Even if we can’t do so (reversibly – it’s not too difficult to make it permanent), might there not be intelligences “Out There” who have done so? What if we found one of their slow sail-ships? Would it seem like a funerary barge, filled with strange freeze-dried corpses?