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Car production in the us costs about a million tons of steel per year which is maybe 99% recycled. Say a rocket costs 100 tons and is expendable. Launching 100 rockets yearly is a decent share of global materials consumption.

Is the cost of the space program misleading when expressed in monetary terms?

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  • $\begingroup$ Just as a data point numbers for Falcon-9 FT dry weight are "only" about 15 to 25 tons, (1, 2) and a lot of that is not steel! Aluminum and some carbon composites are used as well. $\endgroup$ – uhoh Sep 9 '19 at 4:33
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    $\begingroup$ If I understand your question correctly, you seem to assume that "monetary cost" equals "cost of the materials". However, that assumption is far from justified (both for cars and for rockets). The expensive part is the work that has to go into the design, development, testing, and manufacturing. And while some materials are expensive, they form just a fraction of the total weight of a rocket (e.g. high-temperature alloys used in the engines). $\endgroup$ – TooTea Sep 9 '19 at 7:25
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Let's refine your calculations a bit. Worldwide, less than 200 rockets are launched each year. They have an average empty weight of 30 tons (rounding up a bit), which is mostly aluminium. That adds up to 6000 tons.

This is a tiny fraction (0.001%) of total aluminium production (60 million tons).

  • if it were economically feasible to recover rocket stages for their scrap value, it would be done already. In fact, when a rocket is launched over land (all Russian and most Chinese launches), the spent stages are routinely recovered and scrapped. Recovery from the ocean is far more expensive than the value of the metals, so this is not done.

  • the fuel is more valuable than the metals. A rocket with an empty weight of 30 tons contains ~500-1000 tons of fuel and oxidizer. There's no way to recover this. A single Ariane 5 contains ~ 500 tons of solid fuel, which contains 20% aluminium. I suspect more aluminium is used in solid fuel than in rocket structures.

  • we routinely throw away far more than 6000 tons/year. Ships sink and are left to rust away. Containers wash overboard. Metals including aluminium foil go into landfills, etc. etc.

And about the cost being misleading: Aluminium costs € 1500/tonne, so there's € 45000 worth of aluminium in a launcher. The launcher costs € 60M, so the materials costs is dwarfed by the cost of R&D and labour.

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  • $\begingroup$ I heard this also spun as an "Why reducing launch costs for programs doesn't work". At the end of the day, most of your cost goes into labor hours for design and manufacturing, and a vast majority goes into operation (especially for comsats). In terms of GPS sats, the launch cost ends up becoming >5% of the overall program cost. Reducing materials cost matters less in this way. $\endgroup$ – mothman Sep 10 '19 at 7:01

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