What absolute rubbish. I went into the article expecting to have my mind changed and was sorely disappointed. The author makes some basic mistakes. First, while

What absolute rubbish. I went into the article expecting to have my mind changed and was sorely disappointed. The author makes some basic mistakes. First, while they correctly point out that most asteroids are small and the distances between them vast, they incorrectly infer that this automatically makes asteroid mining impractical, saying any given asteroid would yield just a few grams of useful minerals. No one is proposing mining individual grains of dust. Rather, we will probably first mine asteroids ranging in diameter from several dozen meters to several miles; such asteroids can potentially contain substantial quantities of ore. Second, the author makes it sound like we have no idea what minerals any particular asteroid will contain, and must blindly sample the asteroids until we stumble upon a valuable one by chance. This is also false. Asteroids generally fall into one of a few basic types (C, M, and S), each with different compositions. Of course there is some individual variation, but these days we can get a reasonable estimate of the composition of an asteroid from it's orbit and from spectrographic analysis. Third, the author makes some trite observation about whale oil and infers that technological progress here on Earth will obviate any need for asteroid mining. There are several problems with this, but the simplest ones to me are 1) not every resource has a substitute (water, for example), 2) just because people have often found substitutes for resources doesn't mean they will continue to do so in the future. Regarding the second point, many economists have pointed out that rates of technological innovation are decreasing (see The Great Stagnation by Tyler Cohen for a good introduction to this line of work). This suggests we can not unthinkingly rely on technological progress to improve our access to dwindling resources. Another aspect of this issue the author conveniently ignores is the environmental destruction associated with mining minerals on Earth, which gives some motivation to mining them in space. Finally, the author makes one final error, but it's a doozy: they assume the only motivation for space exploration is economic, claiming that anyone familiar with basic economics will recognize the futility of space exploration and that colonies on the moon or Mars are nothing more than a pipe dream. There are many possible reasons for space exploration and colonization, only some of which are based on economic gain. What I can't stand most about the article is the arrogant certainty with which the author writes; the gist of the article is "obviously we will never mine the asteroids or colonize Mars. Anybody who knows economics can see that."