Thursday, April 20, 2017

Flat Earth Follies: Mount Denali from Hilltop Ski Area

Another Flat Earth Meme - another pile of lies...

It's either a lie because they purposeful get these things are wrong or they are lying about their level of expertise.  I'll let you judge which one but this level of dishonesty/incompetence is inexcusably disgusting.

Flat Earth Claim:



#RESEARCHFLATEARTH it implores us.  What a load of crap.

It seems to be a nearly universal rule that #FlatEarthers never include any reference data to back up their claims.  This meme is full of assertions which are just flat out WRONG.

Let's unpack...

CLAIM: 4.5 miles of missing curvature


If my eye was half-way underwater at ground-level then it would be 4.5 miles of curvature, relative to THAT point from 190 miles away.  Since our viewpoint is NOT at ground-level -- it's some 240 meters up and the mountain (nor horizon) is 190 miles away -- this claim is complete nonsense.


These factual differences make a HUGE difference in our view, as I will show below.

CLAIM: Mount McKinley


I don't think so TIM.


First of all, fuck you for calling it Mount McKinley.  Secondly, that is very clearly NOT Denali.

Why do flat earthers feel the need to lie about everything?  Oh right, the facts don't support their claims.

DENALI itself is ~140 miles away -- and guess what you CAN see Denali from there also (see FEI Calculator), only about 7459.5 feet would be 'obscured' from here out of the 20,310 feet -- so more than half of Denali should be visible.



CLAIM: 140 miles


Um no.  That's 140 KILOMETERS to the mountain shown, not miles.  And the view shown from that elevation over that distance is completely consistent with the Globe model.

From 140 km at 240m up the obscured value is only 1851.8 feet - or about 16% of the height of that mountain range.  Which means we should still be able to see 84% of the height -- looks about right to me.



CLAIM: 190 miles away (horizon?)


I can only guess that they have pulled this number from their sphincter, like everything else here.

For 240 meters elevation the horizon would be sqrt(h(h+2×R)) which is about 34 miles to the horizon.  Beyond that distance we would expect to only see things that are tall enough to stick up beyond the horizon distance.

Here is most of the above information in one compact 'counter-meme':


Is it possible they tried their level best and got everything so wrong?

Here is the view from peakfinder -- notice how the 20,310 foot tall Denali is the same apparent height of Mount Susitna, which is 65.4 km away but only 4117 feet high and Mount Spurr which is 136.7 km away and 11070 foot high just barely peeks over the line?


The distance alone does not account for the change in apparent height.  Yes, more distant things would appear smaller due to perspective but not in this proportion.

We can verify this by applying the law of perspective which is very simple -- the angular size (α) of something in our field view is given by dividing one half the size (g/2) by the distance (r) -- which gives us a slope, which we convert to an angle with the arctangent function and we double that.

α = 2*arctan((g/2)/r)

Let's try it:

Denali - 225.0 km - 20308' (6.19 km) - angular size: 1.576°
Mount Susitna - 65.4 km - 4117' (1.255 km) - angular size: 1.099°
Mount Spurr - 136.7 km - 11070' (3.374 km) - angular size: 1.414°

So you can very plainly see that peakfinder is taking into account curvature of the Earth.

You can also line this up with photographic evidence and compare -- and you'll find that your view of the Earth matches the view expected ONLY when we take the curvature into account.

This is as close to an 'original' as I could find for this image - I wasn't able to find the source, nor a very high-resolution version.  But this version makes it extremely clear that this isn't Denali.  If you find a high-resolution version or the original source please let me know as I would like to credit them.


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