When you learn something new, change your mind.

A few days ago I finished listening to the book Range by David Epstein, and it was good. Essentially it described to me something that I already knew, but in a way that I hadn't understood or articulated. People that do a range of different sports or jobs before getting to their current sport or job often have more success than people that specialize very early in their sport or job. 

One way this manifests is that people with a range of experience can give an analogy about a situation to describe it in a different way, and that might provide some insight to a group that they didn't have before to the current situation. He spends one chapter of the book talking about people that forecast different events, and the people that are able to forecast the best often have the largest range of experience, and relentlessly change their minds about thing as new information is presented. So I took some time to reflect on myself, do I have a good range of experience? Am I open to changing my mind on things? What have I changed my mind on in the past?

It both made me feel good about having changed my mind on a number of things, and also made me feel a little bad that I didn't seek out more diverse opinions on topics to intentionally change my mind more often. To give a big example, but also one that moved rather slow for me, 20 years ago I didn't think that universal healthcare made sense, it would be too expensive, end of story. However, over the last two decades, I've learned how much money insurance companies make, and how much money pharmaceutical companies make, and how much debt it takes to become a doctor, and how in many cases, like PEPFAR a dollar a day can actually save a person's life for decades. Would you save a person's life for $1.00 per day? I think that's a no brainer, yes, every single time. Raise my taxes to make that possible. I can pay an extra $10/day to save 10 lives a day. The United States is a wealthy country, how is it countries with half or a third of our average income per person can have universal healthcare, but we can't?

To give another example, I still can't believe I'm in manufacturing. In a few months it will have been five years, and admittedly my design skills are a little rusty. I always perceived manufacturing as dirty, dangerous, poorly illuminated, but the reality today is very different than the factories of 50 years ago. Plus there is a certain satisfaction to building something, you get to see the thing that you were working on come to fruition. In the design world you can spend years working on something, and then it can actually get canceled before it becomes reality, and that happened to me several times. Of course the risk in manufacturing is you build a whole new factory and never get to take the factory to production.

Another example is the three stage rocket. I need to write this one out more, but nearly three years ago I watched two coworkers debate a two stage versus a three stage rocket, and despite the fact that nearly every rocket company works around two stages, I've actually come down on the side of a three stage rocket. Why? Well, we know a first stage rocket can be reusable and land vertically, so now it's just a matter of making it more reusable and easier to reuse. We also know that orbital vehicles like the space shuttle can be reusable. However, due to the rocket equation, a two stage rocket just never really can get that much to orbit. So a solution that no one has implemented is make a three stage rocket, with stage one landing back on land within a few miles from the launch pad for easy refurbishment between flights. Stage two landing 1000 miles away on a barge, or better yet some piece of land, and then stage three being orbital, and either disposable, or reusable. Trying to make a second stage orbital and fully reusable means that the payload capacity will be small compared to the mass of the second stage, something like 5% of the dry mass of the second stage. It's like saying that you need a 5,000 pound SUV to deliver 250 pounds total to the destination... which is only two people and no luggage if the people are small. And the problem is reentry is always going to be harsh on vehicles, so that second stage in a three stage vehicle that is suborbital, you really want to minimize the reentry stress on that stage. 

The point of these examples are it's okay to change your mind, in fact, it's good when you are presented with new information. Often the ideal answer isn't clear and it can take a lot of research to find the best answer that incorporates all of the available data. It can definitely be hard to search out an opposing opinion at times, but it's often worth is to find a better solution.

An Economic Challenge of Rural Areas

I grew up mostly in rural areas, later in elementary school I lived in a town of 900 people, and then I went to middle school and high school in a town of about 2400 people. In the first town, which was more remote, the economy was definitely more agricultural. In the second, by a quirk of fate there were some manufacturing and professional services businesses in town, as well as a share of farming. In 2016 when I moved from a small city of 50,000 people to a town of 9,000 people, I didn't really expect to learn some of the things I learned. 

One example, in the town I lived in from 2016 through 2018, the hospital had closed, and there was an urgent care instead, along with a few private family medicine clinics. In a nearby town only 20 minutes away there was a hospital. Hospitals are a good thing for a community. They often have good paying jobs, they provide some stability, and when people get sick or injured it's good if they are closer to a hospital than farther away. So how do you keep a hospital open? Essentially two ways, either you have enough paying customers that it operates with a small profit (or a non-profit with a balance at the end of the year), or the second option is that someone funds the hospital even though it loses money. In the second example that could be the federal government, it could be a wealthy donor, it could be community donations. I don't really know how you get that second example to work across the whole USA in thousands of small towns, I don't have an answer for that. It seems like the federal government is the right organization to prioritize keeping hospitals open, but hospitals are a hyper local organization, so from another valid point of view, the solution to keeping each one open should be local.

Another way to phrase it, in Iowa I used to bicycle with an internal medicine doctor, and one day he told he me he sees about 5,000 patients a year. Using that as a metric, we could say that it takes roughly 5,000 patients to fund one doctor. The number is probably somewhat less than that because there are specialists, pediatricians, OBGYNs and others that see a similar number of patients a year, but only see a subset of the population. Even if we reduce that by about 2/3rds to say 1500 patients to justify the salary of one doctor, as you get to the smaller towns of say 900 people, it gets hard hire and maintain a doctor. The doctor will likely be paid less than in a larger city, and will likely have essentially zero opportunity for career growth, whether that is teaching or getting into hospital management or learning a specialty. 

Again, I don't know what the solution is. I like the idea of universal healthcare, and specifically with funding for medical professionals in rural areas that is not directly related to how many patients they see or what type of tests and treatments those patients require. In other words, something that says, yes there is $X minimum amount of funding for doctors and nurses in towns of Y number of people every year, regardless of how sick or how many tests those patients are in a given year. In the current USA medical system there is an incentive for more medical tests, more prescription drugs, but not for keeping people actually healthy or having easy access to a doctor. I think that's wrong, and that's a systemic issue that applies to most of the whole USA medical system.

That's one small example, but it's a great example, because it's something that does affect nearly all small towns. Another example is business and industry. For example manufacturing, that's an easy one to talk about. NPR recently did a series about is manufacturing special, and the short story is that it is special, because it's something where blue collar jobs exist that don't require a college degree, yet manufacturing jobs pay well and typically have some level of career progression available, and overall they aren't especially dangerous. When I was living in the town of 9,000 people I worked in a facility that did manufacturing and had a total employment of about 400 people. I didn't actually directly support the manufacturing that happened there, I actually supported a manufacturing facility in Mexico. It was interesting because there was a pervasive fear that at any given time one mistake by any of the engineers would lead to the whole facility being shut down. I always thought that was ridiculous, but that fear is grounded in some very valid lived experiences. On the street where the factory was, there were the remnants of other businesses, especially one large warehouse that had shut down and laid off quite a large number of staff. That business closing, along with the local hospital closing, were both regularly talked about around town. Definitely not an every day sort of conversation, but every few months it would be brought up.

The real fear there, was that people would have to move if the business shut down. The people employed at the factory, maybe 200 of the 400 would stay, but the others would likely have a very very difficult time finding local work, and decide to move farther away. That's a big fear. It's something that is based on reality that happened in other towns. In a big city, like Denver, one company closing, even a big one, doesn't have much effect to the million plus people living there. There is an inherent stability to a large population economically, it's a diversified economy that not every small town has the luxury of.

I don't have all the answers, ha, I don't even have many of the questions to ask. I read probably a decade ago that many rural American communities are headed toward the minimum number of people to support the agriculture in those areas. I think that's probably true. And frankly, it probably doesn't include hospitals or much industry like manufacturing. Now every town is different, there will always be entrepreneurs who want to build businesses in their hometowns. There will be local and regional companies, maybe not one in every town, but when a few in neighboring towns close, the one remaining will likely have more business. 

The Christian Church in the United States is in Trouble

In the last 20 years, I have regularly attended six different churches. That's not a large count, but it is a fair number. The church is changing. Some of those churches have been healthy and stable, but a couple of them have been hanging on by threads. I'm not talking about actual Christianity, because as a believer, I believe that God has got it all taken care of. I'm talking about the human organization side of the Christian Church, the various congregations and denominations all over the country. They are struggling.

My wife and I are Christian, but when we go through the list of the friends we spend the most time with, only a few, maybe 15% of them, are Christian enough to regularly attend church. The ideology of the church has turned off many millennials, who see public figures that are not accepting of the poor or sinners. The church doesn't really appear to be a loving and caring place when viewed through their most vocal public figures. When public church figures are actively campaigning for a person that seems to have no values, and certainly not strong Christian values, people get turned off to any thought of moral aspiration coming from that group. As the saying goes, it takes years to build trust, and seconds to lose it. Of course, when you get into a church congregation, they are typically very caring, but it takes time and effort to get into that group. Many churches have somewhat stale congregations, where the same people have gone for 10+ years, and they all know each other, and aren't necessarily looking to add new people, so they don't feel especially welcoming. 

To give a specific example, I once went to a church that had a declining membership, and the people were worried about the church finances. Just down the street was a Hispanic church start up that was meeting in an old hardware store, and I suggested, why not share the church with them, let them use it Sunday afternoons? That's was actually scoffed at as something the congregation would never go for. Yet, that's one way that the Christian Church in this country has a chance at survival is to show that we're more united than we are divided. 

Right now baby boomers are keeping a lot of congregations alive. When they pass away, a lot of churches are going to close. To some extent I do think retirees for decades have filled a lot of roles at churches because they often have more time for volunteering than the younger working population has. Another challenge is that there is a shortage of pastors. Here is an occupation where often it takes several years of additional schooling, and then the pay is often very low, it's a degree without a positive return on investment. I've also seen a few churches where they essentially push the pastor out because they didn't like something that he or she did. Not that the actions were a fireable offense, simply that church leaders didn't like the pastor's words or actions. Church politics can be tough. Every time a pastor is pushed out of a church, people get upset, and some leave, because it's an unloving act by the congregation.

I don't know what the future holds for the Christian Church in the United States. I hope it's good, and membership is strong, but I don't know, it's hard to see that in the next decade or two.

Humans aren't going to Mars anytime soon.

For a very long time I wanted to go to Mars. Yes, I wanted to take that three year long lonesome trip through space with a small crew and a communication delay. It's the adventure of a lifetime! The adventure of a generation. It's hard to really conceptualize how far away Mars is, and while that is part of the appeal, I now realize just how significant the challenges are. The last 1.5 years I've been working on a lunar lander, which I viewed as a great step into seeing what it takes to send a lander to another body in the solar system. I've learned a tremendous amount about travel beyond Earth in the last 1.5 years. None of this is really proprietary, in fact, most of the learnings are from the Apollo days in the 1960s and 1970s, with only a few from the recent Mars rovers.

When you read the news articles, one of the recurring themes of a human trip to Mars is that we don't have the technology to do it. I would see that statement and not truly understand what that means. So let me give a few examples of the technology that we don't have ready yet:

• We don't have a spacesuit to be used on Mars. This is modestly significant. Mars has a lot of advantages, it has a thin atmosphere, the temperature is more temperate than the Moon or even the International Space Station, so the suit will likely be slimmer than the bulky in space suits that are currently used for spacewalks, and were used on Apollo on the Moon. So while it should be easier to design and manufacturer the suit, as far as I know there has been no serious work on a Mars suit yet, and it's the kind of thing that really will need a few years of dedicated work before it's ready to be used by humans on Mars.
• It's not clear how to launch a vehicle from the surface of Mars back into Mars orbit. There are a couple sub points here. 
• First, the baseline architecture for the Mars Sample Return mission costs around $11 billion, and that's to get back about 15 kilograms (34 lbs.) of samples from the surface of Mars. One astronaut weights a lot more than 15 kilograms. Now, Rocketlab proposes they can do it in house for only $2 billion... but remember this is for low tens of pounds of payload from the surface of Mars back to Earth. This first point being it's very expensive, and we've never done any launch from the surface of Mars. 
• Second, a human lander will likely be significantly different than the small sample return rocket. SpaceX is proposing using Starships, which definitely work on paper, but there is a question about how exactly to fully fuel those Starships. Mars has a lot of CO2, so just bring along a big garden and turn that into a lot of oxygen, which you can cool and condense into liquid oxygen. However, to get the hydrogen for the sabatier process, I'm not clear on exactly how to get that. The baseline is to harvest water, and then do hydrolysis to get hydrogen and oxygen, but we've never harvested water on Mars. However, you're going to need likely at least a hundred metric tons of water, maybe 1000 metric tons of water, and that's a lot. We haven't even harvested 1 kilogram of water, let along the possible 1,000,000 kilograms that could be needed to launch a large rocket off the surface of Mars. Now it's possible to take all of the return trip fuel with you, say bring five ships, one with the people, and four with fuel, and just refuel the human ship on the surface and/or in Mars orbit, and leave the four tankers behind. But the point of this is that exactly how we are going to launch a human crew sized vehicle off the surface of Mars is not clear and will require a few years of engineering to make sure we can actually do it.
• My assumption is that almost everything on a short Hohmann transfer orbit to and from Mars with an astronaut crew of say four people will essentially use expendable consumables. What I mean by consumables:
• Oxygen for breathing and water for drinking, they will essentially take a whole lot of each and then CO2 and urine and excrement will essentially be dumped overboard. Some amount may be recycled, but in the event the recycler fails, you'll need to have a lot of spare.
• Clothing will maybe be washed by hand on Mars, but for a fifteen month stay it has to be expected that clothing, boots, gloves, and likely whole spacesuits will wear out. So does each astronaut need to bring one Mars suit and some spare parts like o-rings, or four whole spacesuits? Again, we don't have a good baseline for how we will wear out clothing on Mars. 
• You're going to have to take a lot of food for the three year trip. We probably can't grow potatoes fast enough like in the book and movie The Martian. It may sound super minor, but the 33 month trip will need roughly half of the time in microgravity, and half the trip at 1/3 Earth gravity on Mars, and the systems for food and living will need to work in both gravity environments. Again, sounds trivial but I'm not sure we really know it will be that easy.
• We're going to need a lot of solar panels, a whole lot. I don't even know how many. Let's say that one human for habitation and some driving around the lunar surface needs 10 kilowatt hours per day, and four people land on Mars, that's 40 kilowatt hours per day. Given that solar panels are less efficient on Mars, you're going to need a lot of solar panels. And honestly, depending on the amount of driving that is baselined, as well as electricity needed for food production experiments or rocket fuel production, 10 kilowatt hours per person per day could be far too little. Again, this is an area where presumably we can modify already existing solar panels, and batteries for use on Mars, and we don't really have to worry about clouds on Mars, just the changing of the seasons, but it's going to take some work to make a mass efficient system.
• All of the pressure vessels, engines, heat shields, and human habitations, assuming that they are the only one of their kind, will need to be repairable. The risks of a crack or accident leading to higher than expected pressure loss will necessitate the ability to repair these pressure vessels. Repairs have been done on the International Space Station, and Apollo 13 is a famous case study in making do with what you have.  The items for for heat shields, engines, pressure vessels will need to be repairable, because a tiny micrometeoroid could render most pieces of equipment inoperable. Will people need to weld on Mars? Will people need to repair wire harnesses on Mars when a pin gets bent? Will people need to patch holes on their habitation walls? How many o-rings and seals will we need to replace because Martian dust cuts the seals? This is all pretty basic stuff, but a single cut o-ring could mean mission failure. 
• Rover wheels for a human sized rover on Mars is a big problem. The Curiosity rover shredded it's wheels faster than than expected, and traveled not that far of a distance. A human rover will probably go something like 1000+ kilometers in 15 months, compared to the 33.5 kilometers for Curiosity rover in 12 years. In other words, we're going to need better Mars rover wheels, and we're going to need spare tires. Again, this is not trivial and will take years of development here on Earth. While there are full size prototypes that NASA has developed, the whole logistics of a rover and spare wheels is a really big deal. The rover itself would be much more useful if it's a pressurized rover and could make multiday trips farther away from the landing site. This adds a fair amount of complexity and mass to the rover, something that we really should be seeing qualification prototypes of say two years before launch so that we can make sure to work out the details.
• People will get sick and hurt. I've thought about it a lot over the years and I am pretty confident that the single most important person on a mission to Mars, would be a doctor. There are so many different ways that people could get sick or hurt, and it's very possible that we discover ways we hadn't even thought of, such as what Mars dust does to lungs when it gets into the habitation. I'm not actually that worried about radiation, it's a relatively known phenomena and while clearly dangerous, would again be rather known for a three year trip. While this bullet point isn't stopping us from going to Mars, we're going to have to take a small emergency room worth of medical supplies and hope that we brought the right stuff. If a person gets cancer on the outbound trip to Mars, orbital mechanics dictates that you have to stick out the whole mission, because the fuel required to do a direct abort and get back to Earth is not part of the plan. Similarly, there is a psychological component to leaving Earth, and barely being able to even see it in the sky that is a whole new challenge we don't really know how to handle. Presumably the people on the trip will be highly qualified and highly trained and have very strong emotional fortitude, but when you can't see Earth, and there is a five minute communication delay, and your parent died, and the X-band antenna broke so you only have S-band text messages, that's a lot of stress
• Last point, it's going to take a lot of launches from Earth in 2028 in order to land humans and the equipment on Mars, with the capability to launch off Mars and come back to Earth in 2031. In round numbers, if we say one Mars landing ship will carry people, and four ships will carry equipment and fuel, and each of those five ships will require 10 refueling flights, we're talking 55 rocket launches in the second half of 2028, all for this one mission. That's simply a lot of coordination for launches, rendezvous and docking maneuvers, even if 50 of those are short 24 hour long refueling flights. This is certainly not impossible, in fact it's probably even easy. However, rendezvous and docking is actually still not a trivial activity despite the fact we have been doing it for nearly 60 years. So 55 events mean that we need pretty high reliability of all the sensors and mechanisms to make this happen.

I do think that humans can in fact launch to Mars in 2028, all of these technology issues can be solved in the next four years, but in order to do that, we need to work on it as soon as possible. More likely is a 2030s human trip to Mars. 

A final note on the rover, when studying the Apollo missions, the first three landing missions, Apollo 11, 12, and 14 did not have a rover and only covered a few miles walking on foot. Apollo 15, 16, and 17 covered 10s of miles of ground and did excellent science while on the surface of the Moon. Going to Mars without a rover is foolish. And going with only an open buggy style rover is slightly better, but still short sighted. A human can only do a space walk for in the neighborhood of 8 hours, and then there are issues like eating, getting tired, having a bowel movement, and even sleeping. The oxygen and carbon dioxide part is the easy part to solve. If we assume that a Mars space suit is very flexible and an astronaut will be able to do 2 miles per hour, that's a maximum radius of 8 miles that a person could walk. That's wildly optimistic, on Apollo 14 the astronauts struggled to walk about one mile away from the LEM before struggling with navigation and not being able to see the LEM. Similarly on an open buggy with a top speed of 20 kilometers per hour (12 miles per hour) would be able to cover more ground, but that has to be traded with the possibility that the buggy breaks down and the astronauts have to walk back to the habitat. On Apollo 17 the furthest that the two astronauts drove the lunar buggy was about 5 miles away from the LEM, so that worst case they could hike back to the lander. Two buggies would provide redundancy, but also add quite a bit of mass. Also, for people that have not done much off roading, there isn't much point in going a lot faster than those speeds, you're going to be bouncing all over the place even at those slow speeds. The point of all this is to say, without a pressurized rover, you would essentially be stuck on a deserted island without the capability to explore much more than maybe 10 miles in any direction, which over 15 months is somewhat limiting.