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A comment on NASA engineer's 'helical engine' may violate the laws of physics. Parent comment

Re:NASA engineer's 'helical engine' may violate the laws of ... by labawi on Tuesday October 15, 2019 @03:21AM (#21256260)
It is not possible to ride an unanchored (and non-couterbalanced) swing in a vacuum.
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Re:NASA engineer's 'helical engine' may violate the laws of ... by steve_taylor on Tuesday October 15, 2019 @04:57AM (#21256706)
What special properties does an atmosphere confer to a swing?
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Re:NASA engineer's 'helical engine' may violate the laws of ... by dean177 on Tuesday October 15, 2019 @06:27AM (#21257144)
You need “downwards” acceleration for a swing. The vacuum bit isn’t important, it’s the gravity. They probably meant 0g rather than vacuum.
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Re:NASA engineer's 'helical engine' may violate the laws of ... by labawi on Sunday October 20, 2019 @03:06PM (#21306312)
It slows you down :)

The vacuum part was an emphasis on requiring a counterpart to change momentum.

In an atmosphere you could flap your wings, or use electric fans, and argue what it means to ride a swing, but it would be besides the point, as in an atmosphere there is no need for propellant-less engines from the article.

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Re:NASA engineer's 'helical engine' may violate the laws of ... by gpderetta on Tuesday October 15, 2019 @06:25AM (#21257130)
Maybe they meant in 0g?
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Re:NASA engineer's 'helical engine' may violate the laws of ... by SSLy on Tuesday October 15, 2019 @07:35AM (#21257444)
none, but centers of gravity do
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Re:NASA engineer's 'helical engine' may violate the laws of ... by z3t4 on Tuesday October 15, 2019 @06:40AM (#21257199)
If you can move levers, it's possible to rate your body. Maybe the inertia can be used as an anchor? Or you could use a sail.
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