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Comment by purpleblue | Hacker News Reader

Can they just do one more #YOLO flight at a high speed and high altitude as possible and see what happens? Seems more useful and fun than just leaving it to rot.

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It won't make it off the ground. Ingenuity has to spin it's rotors about 10 times faster than it does here on Earth. With that big of a chunk missing there's no way it can fly it'd tear itself to pieces during the spin up.

> more useful and fun than just leaving it to rot

Ginny has an independent solar panel/battery set-up. Perhaps it could be rigged as a lone stationary sensor?

I wonder if it could even use its rotors to periodically blow away dust on the panels?

It can't communicate over long distances, so it wouldn't be able to communicate with Earth after Perseverance drives out of range.

Probably don't want any flying debris hitting the rover.

It's nearly a kilometer from the rover, should be fine.

But I agree that it's better to leave it, download the remaining images and data from memory, maybe leave the software running as an experiment in non-rad-hardened computers on the surface, and eventually put it in a museum, than risk it crashing in spectacular fashion.

The tips of the rotors approach the speed of sound. Around Mach 0.95.

I'm sure someone can do the math on the maximum debris field, but I think it'll be larger than you're thinking.

Agreed: Our earth-based intuition is probably pretty off when the atmosphere creates 1% as much friction as it does here.

I doubt the debris field would be 1km in size. Assume you throw a high-speed small piece of propeller tip debris at the optimal angle at 240 m/s or about 800 fps. I'm sure it goes farther in lower Martian gravity and atmosphere but a spinning lead air rifle pellet at that speed and the optimal high-arc trajectory could barely make it half that far on Earth. None of the ballistics tables have columns for Martian atmosphere or gravity. (Yet! I hope I live to see a day when we could use this information, but not quite as much as I hope that we never have to use this in anger.)

But even in the worst case, you're scattering a 1.8 kilogram robot (more accurately, a few grams of the rotor blades) over an area of pi square kilometers. The chance that a large chunk hits Perseverance just wrong is negligible.

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