Thursday, June 9, 2016

Dave Murphy's Open Letter

There is a petition on petitions.whitehouse.gov asking the government to answer the twelve questions posed in the video entitled An Open Letter To Neil DeGrasse Tyson on YouTube by a fellow named Dave Murphy. Here's his "letter" in video format. I have not found a text version online.


Now, let me mention a couple of things before I even address the questions in the "letter." At the beginning of the video, Murphy calls himself a "former man of science." He has no background in science that I can see in his biography, and in fact he seems to specialize in pseudoscience of many kinds. So, this opening to the letter is, at least, disingenuous.

Murphy then goes on to criticize Dr. Tyson's out-of-hand rejection of the flat Earth. He thinks that the flat-Earth deserves the same respect as new ideas in real science. This is nonsense. You don't earn respect for you ideas for just throwing them out there; you earn it by presenting ideas with substance, that ask real questions about the world, and make predictions that can be tested. The flat-Earth crowd does none of this.

Further showing his ignorance of how science works, Mr. Murphy says "Nothing in science is ever settled." If that were true, no progress would be made in science. Facts are settled, laws are about as settled as anything gets in the world, and theories are settled for as long as they continue to be the best descriptions for observations.

Murphy also says "The scientific method demands that you treat each point of view with respect, as it has the potential to overturn the existing model." Only extraordinary evidence and theories of magnificent explanatory power can overturn established principles. It is through this process that we build on existing ideas to discover more about the Universe. But the flat Earth has none of this.

Lastly, Murphy uses the word "scientism." This is casting science as religion, and undermines Murphy's credibility, even before he poses his first question.

He also says he wants answers in simple layman's terms. Kind of lazy for a "former man of science," don't you think? Flat-Earthers often accuse others of not doing their research. If they have something so important to offer, shouldn't they at least do their homework?

But, of course, when he does get around to posing his questions, his credibility just flies out of the window. These are not legitimate scientific questions. These are attempts (and mighty poor ones) at "gotcha" questions,

Let's have a look at these twelve questions:

1. Why is there land at the equator?
Murphy is off to a bad start with this one. He's referring to the slight bulge of the Earth at its equator cause by the Earth's rotation, which makes the Earth slightly oblate. He includes a portion of an interview with Dr. Tyson in his video which explains this. But, like every flat-Earther, he omits the last, and most telling, part of the interview, meant to give its audience a sense of scale.

Here's a terrific video by the YouTube user fiverredpears on the interview with Dr. Tyson:



So, let's move on from that bit of flat-Earth trickery to his next point. He claims the equator should be covered in water because water is "easier to move" than rock. As if the Earth was made from nothing but water and rock. And if if a spin of one revolution per day has enough force to pull the seas out to cover all the land masses at the equator.

Look, Mr. Murphy, this oblateness, this bulging at the equator, has happened gradually throughout the four-billion-year history of the planet, and affects all of its components. Your out-of-scale diagrams (a favorite tool of flat-Earthers going all the way back to Rowbotham) don't change the physics involved.

Ultimately, it's just a very silly question.

2. Am I able to see the curvature or not?
I addressed this question myself in this blog entry.  But I'll say this much more. Murphy is making some very odd assumptions in the video about how we see, and more importantly how much we see, when we look at the horizon. If you see five miles out, do you see 10 miles across? Only with a 90-degree field of view, and though the total human view is nearly 180 degrees, we can only focus in the middle two or so, and our perception of both detail and color drops off quickly outside that area.

So the answer is, no, for the most part, unless you are very high above the Earth with a nice wide view, you will not see the curve from side-to-side even when you can detect it by watching ships go over the horizon.

3. Why haven't we ever seen curved water?
We have. Every time we can't see something—or even a portion of something—beyond the ocean horizon, we're looking at a curve in the water. Murphy alludes to a very large frozen lake in Siberia. Now, if he would like to travel there, it seems that it would be the perfect place to reproduce Wallace's version of the Bedford Level experiment, since, on top of the ice, you need not worry about your depth in the water.

The experiment can be performed with three tall ladders, some simple wood targets, and an inexpensive spotting scope. And lots of hot coffee. Next question.

4. How are we breathing right now?
This is Mr. Murphy confusing the vacuum of space, which is the absence of matter, with a vacuum cleaner, which actively pulls things into it. The vacuum of space doesn't pull the atmosphere away; it is not negative pressure. We have an atmosphere because we have gravity. If the gravity was stronger (because the planet was more massive) our atmosphere would be denser. Also because of gravity, the air is less dense as you get further from the surface. Because of this, Mr. Murphy's column of rising hot air will not escape the planet because it will eventually meet an area of less dense air through which it can not longer rise.

5. Is the Earth very very small, or is the sun very very near?
The video that accompanies this question is so rife with errors it's hard to know where to begin. No, the "official" explanation (as if there was some government-approved version, instead of a standard scientific explanation) of crepuscular rays (those seemingly divergent rays in the picture) is not light refracting around the Earth. Refraction only comes into play because that's what allows to see the rays in the first place; you can only see light rays that enter your eye, not from the side.

The explanation for crepuscular rays is that they are, indeed, parallel, are coming right at you (which is why you can only see them close to sunrise or sunset), and the angling is an illusion caused by perspective.

So much for refracting, divergent rays, which also pulls the rug under Murphy's little bit about Eratosthenes' experiment.

6. How does a convex lens make light diverge?
It doesn't, at least not between the lens and its focal point. But, since the light doesn't diverge, it's a silly question. So why is the shadow of the airplane Murphy shows appear larger than the plane itself? Perspective. The shadow is closer to the camera than the plane, and so appears bigger. This is really basic stuff.

7. Why doesn't the artificial horizon roll backwards during straight and level flight?
Murphy shows a shot early in this video of a meter labelled "Bullshit Detector." Mine pinned the needle in this segment. He talks of two conversations he had, one with airline crew members, and one with the manufacturer of the airliner's artificial horizon. I see two problems with this. It is doubtful that the crew on this jet knew who manufactured their horizon indicator, and it is doubtful that the commercial jet had a mechanical artificial horizon.

Modern avionics has moved to the AHRS, the Attitude and Heading Reference System which, as the pilots said (if this conversation actually took place), contains sophisticated electronics, including three-dimension accelerometers and magnetometers, and no mechanical rotors at all.

To be fair, though, older artificial horizons are, indeed, completely mechanical devices, which have, as a little research will show, completely mechanical gravity compensators installed.

8. Why is the Coriolis Effect so selective?
The Coriolis Effect does influence planes, just not as much as prevailing winds and the airplanes' engines. Pilots don't think about it because course corrections are made for all forces in play throughout the flight. Artillery gunners and (to a lesser extent) snipers have to compensate up front because they don't get to make course corrections once the projectile has left the barrel.

As is so often the case, the graphic for this is overly exaggerated; the plane (and the guns) are already moving with the Earth, and so the Coriolis Effect is, relatively speaking, quite small.

9. What is the International Space Station flying over?
The Earth. Murphy's evaluation of the change in speed of surface features is wrong; the features do move faster as they get closer, but not as much as the landing airplane, because you aren't as close to them. This is how perspective works, and Murphy's choice of video footage is extremely misleading.

10. How can microgravity be selective?
It can't. Why is it that flat-Earthers identify every little blurry blob of something that moves across the screen in a video shot in space as a drop of water? Murphy's "drop of water" is likely no such thing. And the ketchup bottle has Velcro on it.

11. Why are there craters on the moon?
This reflects Murphy's awful sense of scale. Yes, the Earth is four times the diameter of its moon. But it is more than 30 times its own diameter away from it. That leaves lots of room for debris to miss the Earth and hit the moon.

The Earth has craters, too, and was hit many times in its early formation. But having an atmosphere, and water, does much to erode those features over billions of years.

12. Why don't we see permanent hills, mountains, and valleys in the ocean?
Because the natural physics of fluids (not just liquids) make them tend to find their lowest-energy state. The path of least resistance is to go with gravity (something I keep having to remind my teenagers of when they put bowls in the dish drainer with the opening up) toward the center of the Earth. That results in a surface that tends to be (but isn't always!) perpendicular to the center of gravity.

Why not always perpendicular to the center of gravity? Because, as with everything else in the Universe, there are always other forces at play that have to be taken into account. That's why we have waves and waterfalls and raindrops and all of the other familiar water features that are not, for a time at least, perpendicular to the center of gravity.

The Petition
So, after posting this video, Murphy posted the petition on the White House site, asking the government to answer these 12 questions, despite the fact that he originally posed these questions to Dr. Tyson, who doesn't work for the US Government; he is the Director of the Hayden Planetarium, which is under the auspices of the American Museum of Natural History, a private organization.

As we can see here, it doesn't take a astrophysicist to answer these questions. Mr. Murphy, in fact, could easily have answered them himself if he were interested in the truth instead of "winning" an argument or convincing people of the "truth" of the flat Earth.

The petition, nine days old as I write this, has about 1,050 signatures out of the 100,000 needed to receive a response from the White House. So there's little chance that anyone in the government is going to have to waste their time on this nonsense.

Meanwhile, if Mr. Murphy or anyone else wants to probe the possibilities of a non-spherical Earth, I think they could start with some better questions.

And more than a little research.

Wednesday, June 1, 2016

Yet Another Stupid Meme

One of the things flat-Earthers can't admit to, of course, because it destroys their entire world-view, is that men actually travelled to the moon. It's not only flat-Earthers that contest this, of course, but you cannot seriously believe that the Earth is flat and that we've traveled to the moon at the same time. So it was from a flat-Earther that I ran across this meme:


The implication of this meme is, of course, that they are inside this zero-G plane, faking the moon walk. Hmm. Ostensibly, they are faking photos like this one:


I hope, if you are not completely brain-dead, you can see how ridiculous this notion is. But let's do a quick run-down. First of all, yes, this is Buzz Aldrin doing training in a zero-G plane (though probably not at zero-G, but at 1/6th G to simulate conditions on the moon). That's the only thing this meme got right.

The ladder is a mock-up of the LEM ladder, but it's obvious that the rest of the mock-up looks nothing like the LEM. The background is the walls of the plane, not a picture of the moon surface with the black sky in the background or a chromakey screen to matte it in later (and the notion of placing a chromakey screen in such a tight space is ludicrous to anyone who's ever shot chromakey, especially in the 60s or 70s). The lighting is completely wrong, and couldn't be made right in so tight a space.

Then there is the matter of time. The reduced-gravity effects in the plane are very short-lived. For zero-G, you get 25 seconds of weightlessness for every 65 seconds of flight. The times are probably somewhat longer for 1/6th G, but certainly it cannot be sustained for the length of a live broadcast from the moon, with no cuts to hide the special effects.

And finally there is the matter of the "film crew." For a film crew, they are missing something: any of the essential equipment that would have been needed to film in 1969: a camera, camera mounts, lights, sound equipment, grip equipment. The only reasonable conclusion is that what you're seeing is not, in fact, a film crew.

The other reasonable conclusion is that the flat-Earthers and moon-hoaxers are really reaching in their vain quest to "prove" that the moon landings never happened.

It's going to take more than some stupid memes.