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A comment on Feasibility of a Dune Ornithopter. Parent comment

Re:Feasibility of a Dune Ornithopter by straphka on Saturday October 23, 2021 @03:14AM (#28966378)
Just so you know, those numbers are way off. If you think about it how would a hummingbird consume that amount of calories in half its bodyweight? See https://www.birdspot.co.uk/bird-brain/how-many-calories-do-h...

I mean, when extrapolated to human size it's still 125k calories a day, but 6600 for a bird of 3g is just not possible.

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Re:Feasibility of a Dune Ornithopter by vkou on Saturday October 23, 2021 @04:27AM (#28966666)
They are (deliberately?) juxtaposing calories (the scientific unit of energy) and kilo-calories (the nutritional unit of energy).

Unfortunately, the latter are, confusingly, also called called 'calories', despite one nutritional 'calorie' being 1000x of a 'regular' calorie.

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Re:Feasibility of a Dune Ornithopter by FunnyLookinHat on Saturday October 23, 2021 @09:03AM (#28967993)
I thought it was accurate - k-cal are usually represented as Calories (capital C) as opposed to the individual unit of measure: calories.

See: https://en.wikipedia.org/wiki/Calorie

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Re:Feasibility of a Dune Ornithopter by adrian_b on Saturday October 23, 2021 @06:23AM (#28967132)
Yes, that must be the source of confusion.

6000 to 12000 calories, not kilocalories, per day, means 1.5 g to 3 g per day of sugar, which is plausible for a humming bird.

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Re:Feasibility of a Dune Ornithopter by chrisseaton on Saturday October 23, 2021 @07:14AM (#28967376)
125k calories is about half a chocolate bar. It’s not a lot.
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Re:Feasibility of a Dune Ornithopter by alisonkisk on Saturday October 23, 2021 @08:18AM (#28967706)
Only the "6,600 to 12,000 calories per day." is way off, because it's physics cal not nutritional (k)cal.

And it's more like 100lb of hamburger for a human, not 300lb.

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