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The comet conundrum

By Jon Kelvey

February 2023

Hollywood loves its comets, but many of those in the planetary defense field are more focused on the threat of an asteroid strike, given the long odds of a comet smashing into Earth. Who is right? Here’s what Jon Kelvey found out.


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So you think you know lift? Better read this

By Ben Iannotta

February 2023

Given how deeply air transportation is woven into modern life, it’s surprising that the precise workings of aerodynamic lift remain a topic of debate among the experts. To sort all this out, I met on a video call last month with Paul Bevilaqua, retired from Lockheed Martin Skunk Works, and Haithem Taha of the University of California, Irvine. I learned about several myths and at least one collapsing theory. Here is our discussion, lightly edited and compressed.


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