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How fast are you?
http://predatorhaven.blogspot.com/2013/03/how-fast-are-you.html
Speed is a funny thing. More precisely, it is a relative thing.
If two cars are travelling in the same direction on an interstate highway ~ in adjacent
lanes and at the same speed ~ and if driver A looks at driver B, neither appears to be
moving relative to the other. But when driver A returns his/her attention to the road
and the passing landscape, suddenly the feeling of speed returns, as apparent motion
is visualized with reference to the motionless ground.
Now suppose that both drivers pull over at a rest stop. Both vehicles are still, relative
to each other and relative to the landscape. But is their speed really zero? Not really.
Even when you are standing still or lying down, you are hurtling at mind-bending speeds.
How is this possible? Here's how ~
<snip>
So what's with the interweaving objects in the GIF image at top (click to enlarge)?
That is a sped-up version of what you might see if you were aboard a spaceship traveling
parallel to the sun's path ~ the objects are the planets of the Solar System. This baroque
dance is a far cry from the static concentric orbits usually depicted in illustrations
(see below - sizes are to scale, distances are not). Caveat ~ this image is distorted
by speed, and controversial in that it seems to portray the solar system moving in a helical path.
The planets do not trail behind the sun, at least not perceptibly. Still, it's an interesting
exercise in visually separating the motions of the Sun and planets.
If two cars are travelling in the same direction on an interstate highway ~ in adjacent
lanes and at the same speed ~ and if driver A looks at driver B, neither appears to be
moving relative to the other. But when driver A returns his/her attention to the road
and the passing landscape, suddenly the feeling of speed returns, as apparent motion
is visualized with reference to the motionless ground.
Now suppose that both drivers pull over at a rest stop. Both vehicles are still, relative
to each other and relative to the landscape. But is their speed really zero? Not really.
Even when you are standing still or lying down, you are hurtling at mind-bending speeds.
How is this possible? Here's how ~
<snip>
So what's with the interweaving objects in the GIF image at top (click to enlarge)?
That is a sped-up version of what you might see if you were aboard a spaceship traveling
parallel to the sun's path ~ the objects are the planets of the Solar System. This baroque
dance is a far cry from the static concentric orbits usually depicted in illustrations
(see below - sizes are to scale, distances are not). Caveat ~ this image is distorted
by speed, and controversial in that it seems to portray the solar system moving in a helical path.
The planets do not trail behind the sun, at least not perceptibly. Still, it's an interesting
exercise in visually separating the motions of the Sun and planets.
11 replies
= new reply since forum marked as read
= new reply since forum marked as read
That gif made me feel just a tiny bit short of breath!
Very cool, my dear Ptah.......thank you!
Two photons traveling toward each other, relative to either photon, the other is traveling at 2X the speed of light.
Take that, Albert!
(suggested by a student)
