Note: This is post #60 in a weekly video series on basic microeconomics.

While the probability of an asteroid hitting the planet is very low, its effect would be disastrous for all of us. Who then should pay for asteroid protection? As Alex Tabarrok of Marginal Revolution University explains, public goods like asteroid defense have some unusual properties that challenge markets.

(If you find the pace of the videos too slow, I’d mend watching them at 1.5 to 2 times the speed. You can adjust the speed at which the video plays by clicking on “Settings” (the gear symbol) and changing “Speed” from normal to 1.25, 1.5 or 2.)

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