ThinksMarkedly wrote:tlb wrote:Obviously I was wrong about hydrogen, I thought that they would have to get it from water (however it would become much easier once contra-gravity was available).
I didn't either. I hadn't remembered that detail until rereading the relevant sections.But still; the planet had been surveyed, so going there was no more reckless than sailing to the new world in the days of pirates and before weather knowledge. It is always "reckless" to leave certainty behind.
There was no direct survey of the Calvin System. They said they had sufficiently-detailed images of it, indicating that the Sol System probably had light interferometry arrays (something that we are actually quite close to developing), possibly multiple AU-wide (something we're not). They said they had seen forests.
But all the spectrography, images, radio and other EM radiation wouldn't tell you if the planet was actually toxic or had untameable large predators. Therefore, going out there and being unable to redirect elsewhere was reckless.
Though I'll grant them one thing: maybe they hadn't been, if the 75-year surplus was meant to allow them to establish a space-borne infrastructure I've been talking about, if needed, near the time of landing. So if it was toxic, they could live in space while working to de-toxify sufficient areas (Grayson did). It's just that no one accounted for the planet being boiled over as a contingency.
And yet, we know the Calvin expedition was launched trying to get away from Sol. They didn't wait; so I do feel correct in saying they were somewhat reckless.Should there be a problem with food on a cryo-ship? Shouldn't there be some hydroponics to feed the small fraction of people that are awake at any time? Now that does require minerals (some of which can be recycled); but wouldn't that be even easier to replenish than the hydrogen?
That was a generational ship, not cryo. So people were alive aboard all the time, keeping probably the same level of population as originally, possibly even growing along the centuries if that was the plan. The text does say that they would need to limit population (my guess is by limiting growth, not voting some people off the ship).
So it's weird that they had hydroponics to keep people alive and fed for ~400 years, but couldn't stretch that by more than 20%. It's true that no regenerative system is perfect - there are always losses - but they weren't out of power, air or water. So I agree with you, they should have been able to add minerals from the Calvin System, especially with the amount of debris that would have been around the orbit of their originally intended home. And carbon, for the organic compounds, is after all the fourth most abundant element in the universe..
What are the major differences between a generation and cryo ship? I thought they are essentially the same.
Please see the new thread created for the topic.