Exposing PseudoAstronomy

April 21, 2014

Podcast Episode 107: Clip Show #2


Gravitational
Force, lunar holograms, and
Rainbows. Yay clip shows!

You get three different claims in this episode, from simple misunderstandings to what some may classify as outright crazy (or, as I like to write, cräZ). More specifically, I talk about whether gravity is an accelerative force, whether the moon is a hologram, and something having to do with rainbows. And no, I’m not talking about the sprinkler rainbow lady.

The possibly newly forming moon around Saturn is a Q&A in this episode.

Graham, I swear I’m getting ready to do the Pioneer Anomaly …

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November 12, 2012

Falling through Earth

Filed under: general science,movies,physics — Stuart Robbins @ 8:18 pm
Tags: , , , , , ,

Just a quick post for today (busy busy here as usual, stuff should settle down a bit come December …). What would it be like to take an elevator trip through Earth from one side to the other?

Apparently, in the remake of the hilariously (poor science-)fiction movie Total Recall, the remake which I have not seen, there is a plot point of taking an elevator trip through Earth’s center from one side of the other. Apparently this is the only way to safely travel from one city to the other … I hope it’s not just some stupid thing that seems “cool” that serves no other purpose than to spend a budget on special effects.

Anyway, I came across a Wired article today where a physicist spends great detail explaining what would it actually be like to travel through Earth’s center. As with all great investigations when we have too much time on our hands, he even does numerical simulations, though it looks like he graphed in Excel … but I won’t hold it against him.

He shows several interesting things, including that the elevator would reach speeds no slower than 8 km/sec (around 5-6 miles/second). That’s really really fast. If he includes the higher density of Earth’s core, then you reach speeds up to 50% faster than that, even.

He also addresses the concept of weightlessness. This is something that all physics majors learn about in detail in Classical Mechanics classes (Physics I on steroids after your first and usually second year). But, I’ve always found it somewhat difficult to easily convey why, without drawing diagrams of circles and triangles, you would be weightless if you were stationary at Earth’s center. He goes through that in agonizing detail before letting you know that, actually, in the scenario in this version of Total Recall, you’d be weightless the whole time because you’re in free fall.

So, as I said, quick post for today, head over to Wired if you have a few minutes to reach about the physics of taking an elevator trip through the Center of the Earth.

July 9, 2010

If Darwin Is Responsible for the Holocaust, Newton Is Responsible for Bombs


Introduction

Well, my class is over, at least one student is complaining about their final grade, and I’m diving back in to trying to get back to work and play. And blogging — yeah, that too.

I hadn’t thought of a good quick post topic to write about lately until I saw someone else’s post tonight about the Discovery Institute yet again reviving the canard that Darwin is responsible for the Holocaust. But the blogger raised an interesting point that I hadn’t thought about before, so I decided to do my own quick post on it.

Darwin and the Holocaust

If any of you are unfortunate enough to have watched that Ben Stein docudrama piece of G-rated-term-inserted that came out a year or so ago, “Expelled: No Intelligence Allowed,” then you know that a common claim of the Intelligent Design movement — indeed, any “anti-Darwin” or “-Evolution” movement – is that the idea of human evolution from a more “primitive” creature is directly linked to and the cause of lots of atrocities such as Hitler’s holocaust, Stalin’s holocaust, forced sterilization, eugenics, and so on.

This isn’t a straw man here — if you’re not aware of these claims, then I invite you to read any of the following:

Any of those will do. And now, let’s be clear: Charles Darwin was born on February 12, 1809, the same day and year as Abraham Lincoln. Conjures up an immediate feeling of “cool” and “he must be great” due to that simple association with Lincoln, right? Contrast that with: Darwinism led to Hitler! Gasp! Shudder! Instead of that warm, fuzzy feeling your gut is now reeling in contempt for the man. Hence why comparison with or association with or even just mentioning Hitler these days is almost in and of itself a logical fallacy (poisoning the well or ad hominem).

Anyway, my purpose here is to present what the ID folks and some Christians are doing in order to attack the formalizer of evolutionary theory and the theory itself, trying to link it with culturally distasteful concepts, happenings, and people. Let’s also be clear: Darwin died in 1882, fully a half century before the Nazi holocaust.

Does This Make Sense?

The purpose of this blog is not at all about evolution. But rather astronomy with some physics and geology thrown in. Hence the connection to the above: Claiming that Darwin was the cause of Hitler’s holocaust, or eugenics, or whatever is the same as saying that Isaac Newton is responsible for bombs. Or for missiles. Yes, dear reader, it’s the same thing. It doesn’t matter that projectile weapons had been in use for, oh, maybe 100,000 years before Newton was born. Or that missiles weren’t created until maybe 300 years after Newton died. Doesn’t matter. It’s the exact same logic that the Intelligent Design folks use to say Darwin was responsible for the holocaust.

Why? Because Newton formulated gravity. Without understanding how gravity works and being able to predict how objects will behave when forces are applied, then we can’t understand how bombs or missiles work. The entire idea behind “The Rocket Equation” (the bane of undergrad physics) wouldn’t have been possible without the gravitational theory Newton formulated or the calculus he is generally credited with creating. (“The Rocket Equation” is a differential equation that describes the motion of a rocket as mass is lost because in a rocket, the fuel is a significant fraction of the initial mass.)

The Bottom Line

Does that mean, from an actual objective view, that Newton really is responsible for missiles? Or is Archimedes responsible for battleships (after all, he’s generally credited with figuring out buoyancy)? Of course not. These men developed ideas of science that could predict how things would behave in the future and explain how things behaved in the past.

Similarly, Charles Darwin formulated the theory of evolution to describe the scientific theory that all creatures are descended from a common ancestor. This theory describes how things behaved in the past, and it is used to predict how things will behave or discoveries that will be made in the future.

So, Darwin Isn’t Responsible for the Holocaust?

No, he’s not. A scientific theory in itself does not have any sense of morality attached to it. It just is. It is neither good nor bad. People can use it and abuse it for good or bad things. Just as Newton’s theory of gravity describes how a missile launched from Iran can strike Israel, it also describes how Apollo 11 landed on the moon and returned safely with its crew. Using a theory to do something that is considered good or bad by the majority says nothing about that theory’s origin, nor should the blame or credit be given, necessarily, to that theory’s formulator.

Science is built upon the shoulders of giants, and if Darwin hadn’t formulated evolution when he did, someone else would have shortly thereafter. Similarly for Relativity — if Einstein hadn’t formulated it when he did, someone else would have very soon after, for the pieces were already out there, they just needed someone to put them together in a new way.

Final Thoughts

If you’re still not understanding this, let’s think of it a different way. Let’s use Christianity. Many Christians, I’m sure, are wonderful people who believe that Christianity stands for helping the sick, feeding the homeless, keeping children off the streets and occupied with productive things, and so on and so forth. Those are the tangible things – I’m ignoring the more spiritual for purposes of this argument.

So under this idea, priests will go to hospitals and sit with people who need to just have someone there with them. Churches will organize groups to work at a soup kitchen, etc.

But, using the exact same philosophy, using Christianity as a justification, the Crusades were launched from Europe, killing tens of thousands. The Inquisition destroyed livelihoods and lives throughout Europe a few centuries later. Literal witch hunts killed dozens in America, but tens of thousands across much of England and some of Europe only a century or two after that.

People will give Jesus credit for the ideas of Christianity and why they are volunteering in a school for underprivileged children, or running a daycare in the church basement. Do they also give Jesus credit for killing hundreds of thousands of people because of everything else people have done supposedly in his name?

Think about that next time you hear someone say that Darwin is responsible for Hitler.

April 11, 2010

What Happens When All the Planets Line Up Against Us?


Introduction

This is a claim that has persisted for a long time, and though people who believe in the 2012 stuff have propagated it, it is not specifically a Planet X / 2012 claim: If all the planets (plus our moon) lined up opposite the sun, they would pull us out of orbit. As the “lolcatz” say, “Oh noez!”

Gravity

The force felt by an object due to gravity is a very simple mathematical function, codified by Newton’s Universal Law of Gravity:

In this equation, F is the force felt, G is the Gravitational Constant, M m are masses of the two objects in question, and r is the distance that separates them.

To figure out how much more or less two different objects will pull on the same object, we can simply remove one of the two masses, so the equation simplifies to F = G * m / r2.

The Math

To determine the relative forces, one simply needs to know the mass of the planets and sun, and the distances between Earth and those objects. This can be found in any basic astronomy textbook or online source. One then can simply plug in the numbers and figure out the forces.

For the sake of argument, let’s say the sun is on one side of this tug-of-war, and the moon, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, and even Pluto are all on the other (Venus and the sun don’t count ’cause they would have to be on the sun’s side). Let’s calculate the force first due to the sun:

Object
Mass (1024 kg)
Distance from Sun (106 km)
Distance from Earth (106 km)
Relative Force
Sun 1,989,100 149.6 0.0059

Alright, now let’s do all the rest, remembering that for the planets, we’ll need to subtract out the distance between Earth and the sun from what are commonly quoted as the planets’ distances:

Object
Mass (1024 kg)
Distance from Sun (106 km)
Distance from Earth (106 km)
Relative Force
Moon 0.07349 0.3844 3.32·10-5
Mars 0.6419 227.9 78.32 6.98·10-9
Jupiter 1,899 778.6 629.0 3.20·10-7
Saturn 568.5 1434 1284 2.30·10-8
Uranus 86.83 2872 2723 7.82·10-10
Neptune 102.4 4495 4345 3.62·10-10
Pluto 0.00125 5906 5756 2.52·10-14
Ceres 0.00095 415 265.4 9.00·10-13

Final Thoughts

This is a really short post because it doesn’t need to be long. To be perfectly honest, I was actually surprised at how small the force of Jupiter actually is on Earth relative to the sun. If we add up the force from all of the other objects, we only get a force that is 0.566% as strong as the sun’s. And then if we take the moon out of the equation because that would be the first to move out of the alignment, then we have a force of only 0.000592% as strong as the sun’s.

If we look at Venus if it were also lined up, helping the sun, its force is 1.90·10-7, or about half as much as all the other planets (again, leaving out the moon), so it would cancel 54% of the effect of all those other objects (again leaving out the moon). The force from Mercury is only about 1/3 that of Mars.

So really, if anyone who makes this claim were to bother to spend about 10 minutes looking up the numbers and plugging them into an Excel equation (what I did), they would quickly see that this claim is simply and utterly nonsense. And this is besides the fact that the planets aren’t lining up any time soon on the other side of Earth to try to pull us out of orbit.

September 20, 2008

Flat Earth Society – Introductory Post

Filed under: flat earth concept — Stuart Robbins @ 11:27 pm
Tags: , , , ,

Like my series on the Apollo Moon Hoax, the idea of a “Flat Earth” will be a topic that I will come back to in future blog entries, discussing some specific claims that are made.  For this first post on the topic, I am going to briefly outline the core concept and explain why it is flawed relative to what we know about the Earth, space, physics, and just plain ol’ common sense.

The main premise of the “Flat Earth” idea is that Earth is, well, flat.  People who believe this idea believe that our planet is a a few miles thick, and everything that is on it – continents, oceans, and ice caps – rest on this flat object (“flat” being a relatively thin object considering how large in diameter it would be).  In terms of basic geography, the North Pole is at the center of this disk, and Antarctica is actually a wall of ice that surrounds the outer rim, keeping the oceans from sloshing over.  I kid you not.  Earth is also the fixed center of the Universe, with everything “revolving around it in a plane level with the flat Earth.”

Flat Earth believers (for brevity, I will call them “flaterthers,” a term that I just made up with the emphasis on the second syllable and the first “a” being pronounced like the “u” in “fluff”, fla-TER-thers) point to five main arguments for their beliefs:

  1. Earth says still in space relative to … something.  In the 1800s, physicists thought that there was a universal “thing” called the “ether,” through which light was supposed to travel.  But an 1887 experiment now called the Michelson-Morley experiment disproved this concept by showing there was no preferred direction (even though they were trying to prove it) in perhaps the most famous “null result” in physics history.  However, the flaterther argument somehow uses this to say Earth does NOT move, there actually IS an ether, and somehow this supports their idea … though I honestly don’t understand how.
  2. The second argument that is made is that Earth can’t possibly orbit the Sun because (a) there’s no way for it to maintain its velocity over billions of years given that it’s traveling through an ether and therefore feels resistance, and (b) because when you orbit an object, there’s an acceleration, and any object “ahead” of the acceleration would get squashed and an object “behind” the acceleration would float away.
  3. Objects on a curved surface would fall off.  They’d slide “down” and when they reached the bottom, they’d fall off.  Hence, according to flaterthers, it’s not possible for people in the USA to be standing up and people in Australia to be upside down, relative to those in the USA … Australians would fall off.
  4. On a curved surface, there’s an inconsistent “down” direction, so if someone from the USA were to fly to Australia, they’d now be upside down!  (I’m not sure why this is a separate argument from #3, but they consider it one on their website).
  5. The only way to keep an ocean on the Earth is to keep it in the large bowl that is bound by the great sheets of ice that we normally think of as Antarctica.  And, the only way to keep the air on Earth is to protect it with a large dome.

Since I honestly don’t understand how #1 is used to justify the Earth being flat (they seem to equate that with Earth being the unmoving center of the Universe), I am not going to address it.  In other words, this is the “Non-Sequitur” logical fallacy – the argument that Earth may be stationary relative to some permeating substance doesn’t say anything about Earth being flat. 

#2 is a little difficult to address because it requires some basic physics concepts and math in order to understand.  First off, there are a few things they say that just aren’t true.  For example, they state that Earth orbits “the sun at a radius of around five-hundred million kilometers.”  This is not true.  Earth’s average distance from the Sun is 149,600,000 km, or about 93 million miles.  At the risk of sounding flippant … every school child knows this.  In addition, they say that “Earth is supposed to be a large, spherical shaped ball of rock flying through space at hundreds of thousands of miles per hour …”  Again, this is over-stated to make it sound impossibly big.  Earth’s average orbital velocity is 29.78 km/s, which is 107,200 km/hr, or about 66,470 mph.  Still pretty fast compared with our every-day lives, but not as big as they make it seem.

Their actual arguments (as opposed to bad math/numbers) are a little more difficult to address with this claim.  First off, no one has actually said Earth has maintained the exact same orbit and the exact same speed for billions of years – that is a Straw Man logical fallacy.  And Earth does travel through a medium – not the ether, but rather the solar wind.  The solar wind is made up of charged particles that are emitted from the Sun and stream outwards in all directions.  In addition, Earth sometimes encounters asteroids that hit it.  Every time something hits Earth, whether it be a giant asteroid or an elementary particle, the momentum from that object is added to Earth’s, and this can act to slow it down or speed it up.  Because asteroids are so much more massive than the solar wind, I’ll address the impact of asteroids:

Earth weighs 5.97*10^24 kg.  That’s a lot.  Let’s look at a dinosaur-killing, mass-extinction-causing asteroid impact – an asteroid that’s, say, 15 km in diameter – or around half the size of Manhattan.  The average velocity of an Earth-crossing asteroid is around 15-20 km/sec, and most asteroids are made of rock, with a density of 3-4 gm/cm^3.  That’s a total mass of 5*10^6 kg, or a difference of 18 orders of magnitude.  That’s about the difference between the mass of our entire galaxy vs. the mass of the planet Mars.  In other words, a dinosaur-killing asteroid event hitting Earth is like you, a person, running into a piece of dust.  Even if that dust is going faster than a speeding bullet, you are not going to feel it.  Similarly, even if Earth gets whacked by these things once every million years, it’s still not going to feel it.  So, unless they are claiming that the ether is more massive than these asteroids, this claim doesn’t hold water (so to speak).

As for the acceleration argument, this is just pretty much wrong.  Our reference frame – the reference frame of EVERYTHING on Earth – is Earth.  We move relative to our planet, our point of view is relative to our planet, and our velocity is relative to our planet.  Yes, Earth goes in a really big circle around the Sun, and so there is a very very very slight accelerating “force outward” away from the Sun, but it is so small that there is no way you can feel it, and you folks who go to Weight Watchers don’t need to try to plan to go and weigh yourself at midnight instead of noon to get a lighter weigh-in.

Argument #3 and 4 I’m going to lump together into the basic concept of a misunderstanding of gravity.  As I said in the paragraph above, Earth is our reference frame for everything in our daily lives, and that’s because it is so big and we are so close to it (relative to everything else) that we are completely dominated by its gravity.  In their third point, they argue that people would simply fall off of a round Earth once they get to the edge that “goes down.”  Their analogy is a beach ball, where if you simply pour sand on the top of a beach ball, it will follow the curve of the ball until it gets to the side and then just fall off.

The reason why this analogy doesn’t work is that the beach ball has effectively no gravity when compared with Earth.  Things “fall down” because gravity pulls it “down.”  “Down” is always towards the center of Earth (until you get beyond Earth’s gravitational pull).  Now, if the beach ball were out in empty space and it was the most massive object around, a grain of sand that was placed on it wouldn’t move … it wouldn’t “fall” anywhere because “down” would be towards the center of the beach ball, regardless of whether the sand was placed next to the part where you blow into the beach ball or placed on the opposite side.

This is why when an American goes to Australia, the American is not standing on their head when they get there.  Throughout the flight (or boat ride) over, “down” is constantly changing so that it always points towards the center of Earth.  In other words, yes, the plane effectively does turn upside down during the flight.  It just does it very very slowly and you don’t notice it because it’s just following the curve of the planet, with the bottom of the plane always facing the surface of Earth.  (And as a side note, if you go to Australia, stay longer in that country than it took you to fly there, speaking from personal experience.)

As for argument #5, I really just have to resort to the ad hominem response:  This is absurd.  The belief that Earth is covered by a dome to keep the air in and that the edge is a giant sheet of ice to keep the ocean in is a juvenile concept that requires massive conspiratorial claims to maintain (which they do) since it negates space telescopes, the Apollo lunar missions, and expeditions to Antarctica, among other things.  In addition, it flies in the face of simplicity, plausibility, and most people who are older than 5.

That’ll wrap up this post on introducing the Flat Earth concept (and flaterthers).  In future posts, I will address more specific problems with it, such as their explanation for seasons, sunsets, tides, their concept of gravity, and other tidbits.

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