IdeaHamstir's comments

They have completed designs using low enriched Uranium. They're not quite as elegant or as small, but they should work fine.

https://fas.org/nuke/space/leu-reactor.pdf

It still produces a fair bit of alpha, so avoid particulate ingestion.

Several orders of magnitude less than Chernobyl. The reactor that lost containment was a gigawatt production plant. A gigawatt nuclear ramjet would be so huge there would be no trouble detecting it and shooting it down near the launch site.

My local utility charges users $5,000 per installed pole for last mile connection. I've priced poles and wire, they are turning a hefty profit for last mile connections.

> Bringing from Earth a few tons of nuclear-powered jet engine to use water as propellant would take building such an engine first. We're not even close.

True, but small scale solar thermal propulsion systems have been built and require minimal mass. Isp is a largely function of collector area (mylar film is lightweight) and reaction mass. If the water is cracked and the hydrogen used for propulsion, an Isp of 1000 is achievable, far surpassing chemical rockets.

I am not sure if any of these programs are still around, but older, generic forms of insulin are available for free or greatly reduced price at many pharmacies to qualified applicants.

http://www.needymeds.org/ Is a non-profit group that helps provide free/low cost meds.

Many pharmacies listed offer free/reduced price insulin. http://www.freediabetestestsupplies.com/free-diabetes-medica...

> What is that number? And do we know that the number would be less without these types of regulations?

https://en.wikipedia.org/wiki/List_of_military_nuclear_accid...

I guess it depends on your definition of "near world destroying accidents".

> With oxygen, water, and power, we can make food.

And carbon, nitrogen, phosphorous, potassium...

The lunar surface seems to have these elements in short supply, though C-type asteroids can provide many of them.

Falcon 9 was designed to be human rated, hence the Dragon capsule. The lag in certification is probably largely due to Russian/USA politics.

> "gee, look how wrong these other stats are"

I get the feeling that the 1% knows how to hide their wealth from the IRS.

Fertilizers in general aren't necessarily bad. It is important for us to actively recycle our phosphorous and potassium, because there is no short term replenishment of these vital elements in the soil. For more information, I highly recommend "The Humanure Handbook": http://humanurehandbook.com/downloads/Humanure_Handbook_all....

Fertilizers do increase the growth rate of plants. However, there is mounting evidence that nutritional content is inversely proportional with growth rate.

The vast majority of nitrogen fertilizers are produced by burning natural gas with atmospheric nitrogen to produce NH3, NH3OH and CO2.

https://en.wikipedia.org/wiki/Haber_process

I guess in a way, the natural gas extraction is a mining process.

Thank you. I will definitely look into this. At the very least, it still makes an effective and fairly high nitrogen organic fertilizer, while drawing down atmospheric CO2. It's so effective at harvesting CO2, ancient azolla sequestered sufficient CO2 (from 3500 ppm down to 650 ppm) to create a global ice age: https://en.wikipedia.org/wiki/Azolla_event

Edit: researchers are still studying the issue, but it seems some plants may be capable of concentrating BMAA, which is highly water soluble. Wheat seems to capture it in proteins of the shoots. I haven't found any further specifics other than cycads, which have a cyanobacteria symbiosis and concentrate it in their seed coatings.

A substantial fraction of the world's natural gas is burned to produce nitrogen fertilizer. This is largely obtained through fracking. Fertilizers, as they are used on the large scale, are pretty bad for the environment.

Been there, done that and have read dozens of research papers on azolla as livestock feed, but there hadn't been any human research when I delved into the subject. That was quite a few years ago, however. I'll dig back into the stacks and see what I find. My chickens prefer azolla over just about anything, I need to grow more of it.

Fry are typically separated from the larger fish with netting. Sure, you could keep them all together, but a huge amount of system resources will be consumed by the endless cycle of breeding and cannibalizing and you will won't get fish to a useful size.

Good to know about the possible neurotoxin. Any suggestions for further information on the topic?

Duckweed is a good tilapia feed, but requires a nitrogen source. Use it to supplement azola, it has around 4% more protein.

The problem with tilapia is they reach breeding size long before they reach useful eating size. Upon reaching breeding size, they pretty much quit growing and put all their energy into offspring. They are nearly impossible to separate by sex. Commercial tilipia is treated with large doses of hormones to hermaphrodize the fish to a single sex and grow those nice sized fillets.

Azolla = free fish food. It obtains both nitrogen and carbon from the air and can double in mass every 2-3 days. Protein content is 17%. Needs only a few inches of water, sunlight and trace minerals.

I've done the math, and while Azolla can't provide 100% of fish nutrition, it can easily provide the majority of it. It can also provide human food and chickens love it. So do pretty much any domesticated animal: many papers have been written about studies on azolla raised hogs, ducks and cows.