The latest on the issue.
It’s a pointless discussion, because it presumes it’s going to be a government program: Apollo back tot the moon again, or Apollo to Mars. We need to be developing capabilities to go wherever we want, affordably. Then let the people paying for it decide.
Related: Howard Bloom says that NASA needs to get out of the rocket business, and start working on an actual superhighway in space. I’m not sure I want Marshall in charge of that, though. To put it mildly.
I read the article earlier, and Europa or bust!
I think Trump needs to mention a particular liquid fuel combination just so liberal journalism majors will have something new to scream about. Maybe they’d even learn something as they Google.
More seriously, I think development of a spinning habitat is the next logical step to anywhere once launch prices have dropped. That would let us answer a tremendous number of critical questions on rotation rates and G-levels for humans, crops, and livestock (including fish, which have a better feed conversion ratio than rabbits, chickens, and pigs). Artificial gravity also makes almost everything vastly simpler, especially machining (which produces chips).
Advances in propulsion are on their own track and will benefit any deep space craft, and so are unlikely to need (or benefit from) an Apollo style push, which would tend to lock in one particular technology. If launch prices are cheap then fielding experimental versions of any new propulsion system becomes cheaper, on top of the benefits the new propulsion system would bring, and that would generate payback on almost any robotic mission.
Then would come the push for accessing in situ resources, whether asteroids, the moon, or Mars. Asteroids have the advantage of a low gravity well, but the moon has the advantage of size and a good location. If you can’t deal with asteroids and the moon, you probably aren’t ready for Mars.
Mercury and Venus also remain on my list of possibilities. Mercury for the solar energy and frequent Hohmann trajectories (if new propulsion results in very high ISP systems), and Venus for the culinary possibilities inherent in its hot atmosphere.
How would you harvest the fish?
With fish, it could also be possible to create a space based food chain so that nothing would have to come from Earth except for fish eggs for genetic diversity and packets of plankton, algae, and num num crustaceans.
A rotating station might not be needed for an aquatic food chain. Some of the links might even do better in zero-g.
I think some small amount of gravity is needed so you have a defined air/water interface. Otherwise you can’t get the fish out of the water without having blobs of the stuff floating everywhere. Plus the problem of fish scales floating around the cabin.
My thought is that the water would be serving as radiation shielding, oxygen generation (via algae), CO2 absorption, temperature stabilization (large thermal mass and easy transport), and waste recycling.
This fish are an added bonus to easily convert food waste and other grains into food. The feed conversion ratio of fish is less than 2 (2 kgs of food for 1 kg of fish) and in some cases approaches 1, such as catfish.
So, it might not take a rotating station but a centrifuge? Separate the fish as Karl Hollowell says below and feed them into a centrifuge and then into a processing line, which has its own challenges.
A couple other things to consider. Fresh or salt water? Saltwater aquariums are much harder to maintain than freshwater. Treating the water could either benefit from or benefit human waste treatment. Fish poo also makes a good fertilizer.
How would you harvest the fish?
It’s worth noting that Earth hatcheries have already solved the harder problem of how to separate the big fish from the little ones by using movable, sorting screens with a particular hole size. That allows small fish their own space to avoid the bigger fish. Similarly, one can use those screens to harvest the largest fish. And we’ve already figured out how to go from a caught fish to dinner on the plate though the process might need some adaption in low gravity or even zero gravity environments (can’t always assume that you’ll have artificial gravity, methinks).
(can’t always assume that you’ll have artificial gravity, methinks)
Maybe aquaculture could be a good lunar industry.
The SLS will be able to launch 143 tons to orbit. Fabulous.
Bloom is playing the game wrong. It should read, “The SLS will be able to launch 143 tons to orbit, fabulous!” And, “In fact, the total development cost of that new rocket will be over $30 billion, what a waste!”
It is nice whenever people repeat the stunning opportunity costs,
Let’s also note that the 143 tons is for the SLS Block II. Which NASA has not even begin to develop yet. It isn’t even supposed to be available until the end of the next decade.
And the Block II has no real growth potential unless they raise the height of the VAB’s roof, which isn’t going to happen.
“I’m not sure I want Marshall in charge of that, though. To put it mildly.”
Exactly. NASA needs to to start consuming large quantities of propellant in space ASAP and let the market take care of infrastructure if and when traffic justifies it. That means focusing on deep space spacecraft and *missions*.
Unfortunately historically infrastructure is something government has had a large hand it, presumably because it offers so many opportunities for graft.