Extraordinary Voyages
I’ve been thinking about deep space exploration, and indeed colonisation. Specifically: thinking about the rates of attrition of such future-voyages.
We as a species have gone from sending actual breathing people to the moon to sending unmanned probes out into the solar system. This is for two, obvious reasons: sending people into space is much more expensive than sending probes (you need to make your spacecraft big enough and life-supporty enough to house whole humans) plus it’s very risky in terms of the potential loss of human life. Are we more squeamish nowadays — if ‘squeamish’ is the right word — about such casualties?
One imaginative paradigm for SF stories about deep-space and interstellar travel is the Age of Sail: 18th-19th century maritime endeavours of exploration, colonisation and trade. Like space travel such voyages took a very long time to reach their destination, and like space travel they were risky. Unlike space travel they took place in an environment supplied with unlimited quantities of fresh air, and (islands and other ports) the possibility of replenishing water and food supplies. Even out in deep sea there might be fresh rainwater and fish to be angled. Space is a much less forgiving environment of course. But then again our technologies have advanced very considerably, so perhaps that cancels things out.
Anyway I was curious about the attrition rate of Age-of-Sail maritime exploration and voyaging. So I consulted ‘Mortality on Long-Distance Voyages in the Eighteenth Century’ by James C. Riley [Journal of Economic History 41:3 (1981), 651–656]
This is what I discovered: the death rate rose (not just the number of deaths, but the rate at which people died) the longer the voyage lasted, from an average rate of 8.01 deaths per thousand per month on shorter voyages (eg England to the Med or West Africa) to one of 23.07 per thousand per month on longer voyages (eg from the Netherlands to the Far East). That’s crew and passengers. Slaves died, surprisingly, at a slightly lesser rate (perhaps because they were valuable to the company only if they arrived alive, where crew did the company a favour by dying and not needing to be paid): Riley’s figures are — for voyages of less than 7 months (between arrival of ships at the African coast and at an American destination) 6.7% of the enslaved group died; for voyages of 9 months it was 13.5% and for voyages over 9 months 18.3. Horrific, of course, in human terms. But compare non-slave emigrants: “18th-century European immigrants to North America died at a voyage-specific rate of 15 to 20%, and sometimes more, on crossings averaging four to five months, and during 1776–1780 British troops sent to the West Indies suffered losses averaging 11%.”
In other words: a group of emigrants sailing to America in the 18th could lose a fifth of their number en route. Extraordinary death-toll!
So the question is: can we imagine a future-society prepared to tolerate that level of attrition? Would you sign-up for an emigration package to Mars, or Sirius B, if there was a 20% chance you and your family would die on the way? Are there stories that factor-in that hideous human cost as an integral part of the future-extrapolation?
