Another aerospace engineer here! I agree with most of your assessment, with some caveats about both asteroid mining and the colonization of Mars.
Asteroid Mining Quibbles
The viability of asteroid mining within the next 30 years will depend on what geologic activity occurred on large metallic asteroids such as 16 Psyche early in the object’s history. If a process created mostly pure gold or a mixture of precious metals and brought it to the surface, then the resulting material can be mined relatively cheaply and easily. Otherwise, mining will be as speculative as you have previously stated.
If surface gold deposits can form on metallic asteroids, we won’t discover evidence for such a process until the Psyche spacecraft visits 16 Psyche. At that point, viable deposits of gold could be discovered by the spacecraft’s Multispectral Imager.
Mining a high quality gold deposit will be difficult due to distance and low gravity.
The Psyche spacecraft will take 6 years to arrive at Psyche. Barring an unexpected breakthrough or the revival of Project Orion, transit times will continue to be absurd. This leads to a horrifically long mission duration (15 years or more).
Companies will need to wait at least half a decade to find out if their spacecraft can successfully extract gold from a high quality deposit. Thus, companies need to succeed on their first attempt.
The light delay of several minutes to several hours will make troubleshooting absurdly difficult, once all expected failure modes have been accounted for and all redundancies exhausted. I am of the opinion that a general intelligence needs to be on site to figure out what went wrong, design an adequate solution and apply said solution to fix the problem.
Both humans and AI could fulfill this role. However, if a true AGI was commercially available to be installed for this mission, then ASI has either been reached or will soon emerge. Hence, humans will probably fulfill the role of general intelligence.
The low gravity makes most cutting tools difficult to use. Large amounts of ballast can be used to make tools like saws work as they would on Earth. Alternatively, high powered lasers could be used to vaporize material attaching a surface gold deposit to the surrounding metal.
Despite all of these difficulties, mining a concentrated gold deposit on the surface of a large metallic asteroid will likely be profitable. Gold is currently about $135,000 per kilogram. Even if Starship brings cost to orbit down to merely $150/kg, then the cost to send a 100 metric ton mining vessel into Low Earth Orbit will be only $15,000,000. I think it’s reasonable to believe that an ion propelled mining vessel with a return payload of 10 metric tons could be built for 500 million dollars. Going by current gold prices, the return payload would be worth 1.35 billion dollars, yielding a profit of 0.85 billion.
It is thought that about 190,000 metric tons of gold have ever been mined, so the gold market should be able to withstand small to medium scale asteroid mining.
Difficulties With Mars Colonization
While colonizing Mars will not be profitable anytime soon, as long as Elon Musk is alive and in control of SpaceX, this won’t matter. I believe that one of Elon Musk’s primary objectives is to send as many people to Mars as possible as quickly as possible. Therefore, in the 2030s and 2040s most of SpaceX’s profits will likely be used to send people, supplies and industrial machinery to Mars. This state of affairs is ultimately unsustainable because Elon Musk will die.
I think there is a less than 1% chance that Elon Musk will have a similarly motivated successor take over SpaceX. In the unlikely event that we do see Elon Musk 2 take over SpaceX, the rest of these bullets will not apply since the Mars colony will still receive the support it needs to develop on a more relaxed timescale.
There is no way for a Mars colony to consistently produce and export the high value, low mass goods it requires to be profitable. As a result, by the time Elon Musk dies the SpaceX Mars colony must have embraced autarky. If it is not adequately designed, the colony will struggle and die as it cannot endure without imports from Earth.
A successful Mars colony will need all of the following factories to keep itself alive. Some of these factories can be built with existing technology, others require new innovations. All of these combined should cover Mars’s basic food, power and fabrication needs.
A solar panel factory that produces solar panels and the machinery required to make solar panels using only solar power, basalt and human/robot labor.
If a concentrated uranium deposit is found and there are nuclear physicists on the red planet, nuclear power can replace solar power and massively simplify the colony.
A factory that can produce space suits using only the resources available on Mars.
Multiple independent methods of satisfying the colony’s food needs. This should include surface greenhouse agriculture, edible algae aquaculture and synthetic food production from H2O and CO2.
A factory that can produce large steel parts using the available energy supplies on Mars.
A factory that can make tunnel boring machines using only materials that can be made from basalt.
A machine shop that can be used to make an identical machine shop to the same or superior tolerances.
A factory that can make batteries.
A factory that can make drills and fasteners.
A factory that can make welding equipment.
A production plant that can produce adhesives, sealants and lubricants from available chemical feedstocks.
Other miscellaneous assembly lines necessary to support the solar panel factory, food production, steel production, general colonial construction and tunnel boring machines.
Unfortunately, some of the most important technologies with long lead times have not been developed. For instance, of all the solar panel factories on Earth, exactly none of them can produce solar panels from basalt using only solar power and human labor. Blue Origin’s Blue Alchemist program may eventually accomplish this, but I’m not sure if their technology will be fully developed soon enough.
Meanwhile, SpaceX (the only Western entity that has the technical knowhow and financial resources necessary to build a Mars colony) has not designed and built a test colony of appreciable scale. I’m disappointed by this since test colonies on Earth and the Moon are the best way for SpaceX to demonstrate and iterate the technologies needed for Mars.
Essentially, a successful Mars colony must be engineered for immediate, total self sufficiency. Otherwise, it will be crippled when subsidized imports dry up, since Mars lacks any viable export resources. Import scarcity will then cause an unprepared Mars colony to suffer a fate similar to Norse Greenland, a highly isolated, mostly self sufficient island economy that slowly crumbled when support from Norway was cut off by the little ice age.
A Chinese Mars colony will face similar stressors. However, China is more wiling to sink resources into a prestige project with a low return on investment. Therefore, I think a Chinese Mars colony will survive until propulsion technology dramatically improves.
That’s valid criticism. I decided to sacrifice national data coverage for increased granularity before 2000. This is because yearly median rent data cuts off in the year 2000. Before then, data is only available at the beginning of every decade. Since I wanted to get a look into the deeper past without sacrificing resolution, I made my substitution.
In retrospect, this was a bad idea.