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If the Earth were 100 pixels wide

distancetomars.com

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Re: If the Earth were 100 pixels wide

#71

Post by aetherson »

chm wrote: post #61
ohazi wrote: post #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...

Distances are in pixels, with the Earth's diameter being 100 px.

Yes, he knows. But the point is: They say they're going 20% of the speed of light (in pixels). But the closest approach of Earth and Mars is about 4.35 light minutes away from each other. So if our virtual speed is 20% of the speed of light, it follows that the page should take more than 20 minutes to reach Mars. And it doesn't.

It doesn't even take 4.35 minutes, so the page must be continuing to accelerate past the 20% c measure, to superluminal speeds, in order to finish in a couple of minutes or so.

Which they don't mention.

Re: If the Earth were 100 pixels wide

#72

Post by incision »

InclinedPlane wrote: post #29
afreak wrote: post #20

Earlier quoted context omitted.

No. Simply put: the core is likely solidified just like Mars and its magnetic field is very weak, causing the weather to be influenced by only its rotation and solar winds. It would be far more difficult to terraform than Mars really. Also a Venusian day is something like 5,800 hours and its surface temperature is capable of melting lead.

Where'd you get the idea that Venus has a solid core?

An extrapolation from the weak magnetosphere [1] I'd guess.

1: http://www.universetoday.com/36161/core-of-venus/

Re: If the Earth were 100 pixels wide

#73

Post by guy2221 »

finnh wrote: post #59
guy2221 wrote: 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...?

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 & Ma…

Okay, it is problematic.

If the camera lens is at a fixed point and then swings from pointing at Earth to pointing at Mars, and we imagine how fast something would have to travel leaving Earth to remain at the center of the camera sensor as it pans - isn't the obvious question "how far away are we??" So it doesn't really work.

It also doesn't work because at different camera locations the Earth and the Mars would have different relative sizes... I suppose we should state that this will be an equilateral triangle formed between the Earth, Mars, and the Camera, the "height" of the equilateral triangle is x, and that Earth will be so many pixels wide on that camera when zoomed 2000x (or whatever).

This interpretation might be specific enough and also match the experience.

Re: If the Earth were 100 pixels wide

#74

Post by JDGM »

S4M wrote: post #39

It's nice but his scale is wrong. He states that the Earth is 6371 km large, while in reality, it's twice that, as 6371 km is just the radius of the Earth, and what you really see is its diameter.

Indeed, and it appears that 63.71km per pixel has then been used to calculate the pixel distances to the Moon and to Mars so in fact they are twice as many pixels long as they should be.

Re: If the Earth were 100 pixels wide

#75

Post by vacri »

aetherson wrote: post #71
chm wrote: post #61

Earlier quoted context omitted.

Distances are in pixels, with the Earth's diameter being 100 px.

Yes, he knows. But the point is: They say they're going 20% of the speed of light (in pixels). But the closest approach of Earth and Mars is about 4.35 light minutes away from each other. So if our virtual speed is 20% of the speed of light, it follows that the page should take more than 20 minutes to reach Mars. And it doesn't. It doesn't even take 4.35 minutes, so the page must be continuing to accelerate past the…

The page flashes for me a couple of times, after which the starfield is still and then rapidly speeds up again. I assume this means that we're travelling with the assistance of warpgates or similar - and at 127km/pixel, it's unlikely that the warpgate or the ship would show on the map.

Re: If the Earth were 100 pixels wide

#76

Post by doktrin »

ohazi wrote: post #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...

I also wish they would have noted the acceleration. Not doing so in fact undermines the point they're probably trying to make (giving users a visceral feel for the distances involved). Can't say it bothered me, though.

Re: If the Earth were 100 pixels wide

#77

Post by vacri »

millerm wrote: post #50
shardling wrote: post #32

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. :)

How about you just imagine the ship is rotating on an axis for artificial gravity generation. Then, if you were looking out the window, you would see the starfield whizzing by. :-) Edited for smiley.

Interesting idea - all the scifi I've ever seen has had ships rotating around the axis of travel, but never orthogonal to it.

Re: If the Earth were 100 pixels wide

#78

Post by JDGM »

ohazi wrote: post #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...

What is bothering me most now is that if Earth is 100 pixels wide then 1 pixel is 127.42km and Mars should be something like 54600000/127.42 = ~428500 pixels away, not the claimed 857000. The radius of planets has been used where it should be diameter and this error seems to have been carried forward throughout the demonstration.

EDIT: This has now been corrected - nice one!

Re: If the Earth were 100 pixels wide

#79

Post by vacri »

shardling wrote: post #32

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. :)

Does it bother you that Florida and the Mediterranean have gone missing? :)

Re: If the Earth were 100 pixels wide

#80

Post by shardling »

vacri wrote: post #79
shardling wrote: post #32

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. :)

Does it bother you that Florida and the Mediterranean have gone missing? :)

What do I look like, a geographer? :P

But yes, while the project looks superficially nice, it seems to be riddled with small errors. Hopefully the author incorporates some of the feedback!

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