If we are going to have an enduring presence on either the Moon or Mars, or anyplace off of Earth, we will need to grow food there. It is simply too expensive, inconvenient, and fragile to be dependent on food entirely from Earth. In fact, any off-Earth habitat will need to be able to recycle most if not all of its resources. You basically need a reliable source of energy, sufficient food, water, and oxygen (consumables) to sustain all inhabitants, and the ability to endlessly recycle that food, water, and oxygen.

The ISS has achieved 98% recycling of water, which is what NASA claims is the threshold for sustainability of long space missions. The ISS also recycles about 40% of its oxygen. However, the ISS grows none of its food. It is all delivered from Earth, with a 6 month supply aboard the ISS. There are experiments to grow plants on the ISS, and these have been successful, but this is not a significant source of nutrition for the astronauts.

Doing the same on the Moon is not practical for long missions, although we will certainly be doing this for a time. But the goal, if we are to have a lunar base as NASA hopes (NASA plans a lunar base at the Moon’s south pole by 2030) is to grow food on the Moon (and eventually on Mars). On the ISS the big limiting factor is microgravity. The Moon has lower gravity than Earth, but it has some gravity and so that will likely not be a major problem, especially since we can grow plants on the ISS. We can also grow plants hydroponically pretty much anywhere, and I suspect this will happen on any lunar base. But a fully hydroponic system has its limits as well.

Hydroponics on the Moon would be challenging for several reasons. First, it is energy intensive, and energy may be a premium on a lunar base, especially early on. Second, it requires a precise balance of nutrients in the water, and those nutrients would have to be sourced from Earth. So it doesn’t really solve the problem of dependence on Earth. And third, hydroponics requires a lot of equipment which would have to be shipped from Earth. We could theoretically leach nutrients from lunar regolith, and this might help a bit, but is also energy intensive and would not be a source of nitrogen.

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A recent study shows pretty clearly that highschoolers benefit from a little extra sleep. We will get to the study in a bit, but first I want to note that this information is not new. Teenagers tend to stay up late, and yet we make them get up super early to be at class, often by 7:00 AM. This is not good for their health or their learning. So why do we do it?

The primary reason is logistical, which is tied to cost. School systems have tiered start times for elementary, middle school, and high school because this allows them to use the same fleet of buses and drivers for all three. Starting high school later, at the same time as middle school, would mean increasing the size of the fleet. There are other stated reasons, but honestly I think this is the real reason and everything else is a backend justification. The other reasons are more tradeoffs, that benefit some people but not others. For example, a parent with a long commute could drop off their highschooler on the way to work. There is more time for after school clubs, sports, and jobs. While some older teens may get home early to watch their younger siblings until their parents get home.

This all points to a main reason our civilization is frustratingly sub-optimal (to be polite). The default is to follow the pathway of least resistance  – everyone just does what’s best for themselves, with people in power doing their best to solidify more power, with vested interests putting the most consistent effort into making the system work for their narrow interest. What is often lacking is any kind of systemic planning, and when that does occur (even with the best intentions) the law of unintended consequences often results in a net wash or even detriment. The world is complex, and we are just not very good at managing that level of complexity. What we need are institutions that can accumulate evidence-based institutional knowledge to incrementally make things work better. But that’s a lot of work, and it’s too easy for vested interests to sabotage such efforts.

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