Whoa! Is That Death Star Wreckage on That Planet?



What if we use something easier—like the moon? I listed the size and mass of the moon in the code above. If you change the values to those of the moon, you still get an impact velocity of more than 2,000 meters per second (4,474 mph). Still no good.Kind of a DragWait, what if there’s an atmosphere to slow it down? When an object moves through a gas, there’s an air drag force that pushes in a direction opposite to its motion. Now, I’m not going to lie—at high speeds this gets really complicated. But we can get a rough estimate of the effect with this simple equation:Illustration: Rhett AllainThis says air drag is proportional to the square of the velocity (v ). So, yeah, the faster something goes, the more important air drag becomes. Here ρ is the density of the air (1.2 kg/m3 at Earth’s surface). A is the cross-sectional area of the object. C is a drag coefficient that depends on its shape—let’s go with 1.0, which is on the high side. (A cube would have a drag…



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