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If the Earth were 100 pixels wide

distancetomars.com

51–60 of 216 posts

Re: If the Earth were 100 pixels wide

#51
Is anyone else a little bothered by the fact that the reported speed was 1/5 the speed of light, yet the flyby necessarily increased to well over the speed of light in order to actually get you to Mars before you got bored and closed the tab? Traveling at the speed of light would have taken 5-20 minutes. Traveling slower than that would have taken even longer...

Re: If the Earth were 100 pixels wide

#52

This simple graphic of the Earth and Moon and the distance between them, to scale, is also pretty thought provoking http://www.traipse.com/earth_and_moon/index.html edit: just large image: http://www.traipse.com/earth_and_moon/earth_and_moon_1280.jp...

You can draw a circle in the palm of your hand, then a smaller circle on the other. Spread your arms out to your side, and that's about the distance from the earth to the moon.

I would get that tattooed if I was into that kind of thing.

Re: If the Earth were 100 pixels wide

#53
post #47

It bothers me a little that they show the motion against a starfield like that -- the stars are so far away that they won't shift perceptibly even on a journey to mars. I mean, I don't have any better ideas, but given that the whole point is to give an idea of scale I wish they'd come up with something else. :)

You're talking about a first-person view, aren't you? But we don't start with that, we start with a third-person view of Earth and then "pan" across the sky... So wouldn't panning across the sky from whatever vantage point actually produce that movement? Same as when you point a telescope and pan, the stars move against your view...?

Hmm, I see what you're saying, but that's not what the demo is trying to convey. At one point it says "You're now traveling at [1/5 the speed of light]" -- that would be nonsense if it was conceived as a panning motion.

e: Ah, but as someone else points out, the trip must actually exceed the speed of light, so the whole thing is nonsense. The author should recast things the way you describe them, and thus solve multiple problems at once.

Re: If the Earth were 100 pixels wide

#54

Here is a photo of the Earth and Moon, with the to-scale distance between them. It makes a great desktop background: http://www.traipse.com/earth_and_moon/

This is really cool, though I would like to see a version in higher resolution with some stars. Not oppressively bright stars, just a hint to remind you that there are billions of billions of violent, fiery balls of self-contained exploding gas out there...

Re: If the Earth were 100 pixels wide

#55

This simple graphic of the Earth and Moon and the distance between them, to scale, is also pretty thought provoking http://www.traipse.com/earth_and_moon/index.html edit: just large image: http://www.traipse.com/earth_and_moon/earth_and_moon_1280.jp...

You can draw a circle in the palm of your hand, then a smaller circle on the other. Spread your arms out to your side, and that's about the distance from the earth to the moon. I would get that tattooed if I was into that kind of thing.

This would depend heavily on the size of the circles.

Re: If the Earth were 100 pixels wide

#57

Here is a photo of the Earth and Moon, with the to-scale distance between them. It makes a great desktop background: http://www.traipse.com/earth_and_moon/

That's actually a pretty cool photo. I was staring at it, as my new background, and was thinking how amazing it is that their mutual gravitational influence is actually enough to keep the moon in its orbit. I guess I mean it's hard to tell just how massive yet, in contrast, how small something like the earth and moon are. That or it's the half bottle of beer I've had.

Re: If the Earth were 100 pixels wide

#58
post #33

it says it is traveling at 1/10 th of light speed. it takes less than minute to get to Mars in pixels, but from other sources I know it takes 13 minutes for radio signal to get to mars. Something does not play here.

This is at the closest pass, when Mars is ~0.5 AU away from the earth; that's 4 light minutes.

It takes 13 minutes from light to get to Mars from the sun, and I think that'll also work out to be close to the "average" time from Earth to Mars.

In any case, you're right that apparently the demo exceeds the speed of light at some point, because it doesn't last for 4 minutes. Someone else suggests that the motion be interpreted as a fast pan rather than a physical motion, which is how this should have been implemented to not contradict the laws of physics. :)

Re: If the Earth were 100 pixels wide

#59
post #47

It bothers me a little that they show the motion against a starfield like that -- the stars are so far away that they won't shift perceptibly even on a journey to mars. I mean, I don't have any better ideas, but given that the whole point is to give an idea of scale I wish they'd come up with something else. :)

You're talking about a first-person view, aren't you? But we don't start with that, we start with a third-person view of Earth and then "pan" across the sky... So wouldn't panning across the sky from whatever vantage point actually produce that movement? Same as when you point a telescope and pan, the stars move against your view...?

You're right, we do start with a 3rd person view of Earth .. but I still interpreted the motion as translation rather than rotation.

By your interpretation, the camera lens is at a fixed point and then simply "swings" from pointing at Earth to point at Mars. But, from such a supposed point, both the Earth and Mars would be fixed points rather than objects with "multi-pixel" width.

So the fact that both the Earth & Mars are viewable as non-point objects implies translation rather than rotation... and so GP's gripe stands =)

[edit: oh, and what shardling says too]

Re: If the Earth were 100 pixels wide

#60
post #47

Earlier quoted context omitted.

You're talking about a first-person view, aren't you? But we don't start with that, we start with a third-person view of Earth and then "pan" across the sky... So wouldn't panning across the sky from whatever vantage point actually produce that movement? Same as when you point a telescope and pan, the stars move against your view...?

Hmm, I see what you're saying, but that's not what the demo is trying to convey. At one point it says "You're now traveling at [1/5 the speed of light]" -- that would be nonsense if it was conceived as a panning motion. e: Ah, but as someone else points out, the trip must actually exceed the speed of light, so the whole thing is nonsense. The author should recast things the way you describe them, and thus solve multi…

Let's get to the bottom of this. It is a panning motion, this much is physically, visually true. Does it still make sense to talk about 'speed of motion'?

Now I'm confused. What happens when you pan from the moon to the sun (during a new moon, when they're ostensibly both visible)? If you do it quite quickly you are panning faster than the speed of light? (In the interpretatio: 'if a physical object remained at the center of your scope as you panned, and started at the moon, it would have to move faster than the speed of light, to follow your pan?)

So if you pan from one thing to another and they're 1 light-minute away and you take one minute to pan, does it make sense you are 'panning at the speed of light'? For something that leaves one object and goes toward another?

What do you think of this?

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