Author Archives: mir

The idea of turning Earth-to-LEO (“low earth orbit”) into a commodity product for human access as well as for hardware opens a number of significant possibilities. As important is the idea of modularity of hardware launch: things done in large numbers become cheaper through mass production; things done in a structured market with multiple vendors become cheaper through competition and proper incentives. This was the topic of the last post on manned spaceflight. But the question is: what does this enable? If we have no big rocket (like the SLS), are we doomed to keep circling the planet? I would argue an emphatic “no” – this model opens up the opportunity to do revolutionary things at costs vastly lower than Apollo.  And by the infusion of the commodity concept from inception, it inherently allows the NASA exploration to feed into more sustainable commercial activity. There was simply no way that Apollo could ever do this, and this is why Apollo was much more of an “Egyptian Pyramid” than an “Eisenhower Interstate System.”

Recently, interest has been stirred again in orbital fuel depots. This is a brilliant alternative to the NASA’s new and doomed big rocket project (the Space Launch System). Doomed because its Apollo style approach means it will be impossibly expensive to build and will consequently also kill any projects in the near term that could ever use the rocket.  Fuel depots make vastly more sense because you can loft fuel on existing rockets. Placing depots in space also means that companies know there’s a market for certain types of launch. Fuel launch should be the cheapest of all. The fuel itself costs almost nothing, and thus the vast effort that goes in to making human rated rockets safe and comfortable for passengers can be completely avoided (only range safety needs be considered). Rockets can also be “right sized” for the market.  Secondary effects of having fuel depots could be significant in terms of businesses that might to refuel commercial and scientific satellites from fuel purchased from these depots.

(NOTE ADDED IN PROOF: Here’s what the former head of NASA’s Johnson Spaceflight Center has to say on the topic – somewhat similar!)

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The thing that makes science unique in all human endeavour is that it is independently verifiable. In this regard, the Berkeley Earth Project (composed largely of physicists outside of the climate community) recently announced their independent assessment of land surface temperature trends. This study was motivated after the impartiality of groups like the University of East Anglia Climate Research Unit and the NASA Goddard Institute for Space Studies was questioned. The Berkeley Earth Project assessment of trends is shown in the figure, below. In fact, the Berkeley numbers are remarkably similar to the NASA GISS estimates, and suggest greater warming than CRU were claiming. In retrospect (and indeed at the time), the idea that such a large number of climate scientists in full view of an even wider audience of geophysicists and planetary scientists could have colluded in a multi-decade-long sham reflects a profound ignorance of how science itself functions amongst a distressing large fraction of the populous. That said, independent checks are an essential part of science, and it’s fantastic that this was done.

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I started out to write a very long article for this blog on US human spaceflight with the goal of getting it online near the time of the last shuttle flight. That didn’t happen and it was probably a bad idea as there’s just too much ground to cover. Since then, NASA has announced a new heavy lift rocket. I think this is a horribly bad idea and am willing to bet, right here, that it will be cancelled in four years, tops. OK, so lots of nay-saying. Does this mean I think US human spaceflight is or should be dead? Most definitely not. Indeed, this period after the shuttle could be used to radically change human spaceflight and dramatically increase the volume and ambition of spaceflight without increasing the budget. Even trimming the budget. Will it happen? Probably not.

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