I got thoroughly confused when they started talking about how the magnetic storm waves were affecting gravity in pockets around the world. Is that plausible? What the heck were they talking about? It was like they were using the terms electromagnatism and gravity interchangeably. I didn't get it.
shareMaybe they shouldn't have been associating them to eachother, but his explanation of gravity was correct (-ish). Heavier mass attracts lighter mass. As heavy as a brown dwarf is (they meant neutron star or something trillions heavier than moon as they said), it would stand to reason it would cause a gravitational pull, but probably one more realistic. And that dust/debris around the moon's impact definitely wouldn't just be sitting there, it would have been attracted. Then again the star probably wouldn't even get stuck in the moon going that fast, it would destroy what it hit, and/or knock the moon aside. Of course, a piece of a star isn't just going to be flying hidden behind meteors.
shareReally much of that debris was from the dwarf star. The dwarf star had hit something else, so it was shattered. To some degree.
shareErrors in the movie:
1) The Moon has absolutely no bipolar (North-South) magnetic field as Earth.
2) "Heavier mass attracts lighter mass." No, no, no! Mass attracts mass, no matter, how heavy or light they are. The Moon pulls Earth with exactly the same force as Earth pulls the Moon, or, another example: Earth pulls YOU with exactly the same force, as you pull Earth.
3) If a "brown dwarf" or what meets the Moon, it completely destroys it (and Earth in the same moment) and the materia of the Moon (and Earth) becomes part of the brown dwarf immediately (read the "Goofs" section).
You're right about #1 and #3, but you're misleading on #2. Mass attracts mass. You're right about that. The force of pull is the same. But since I have less mass, I experience a much effect (moving a greater greater distance). I jump, and I get pulled down 2 feet. The earth doesn't move 2 feet every time I jump. It does move, but like less than a millimeter. So therefore the fact still stands, that a smaller mass (such as Earth) would be attracted by a larger mass (such a star - ie. the Sun).
shareOK, the scientific fact is what I've said, the everyday interpretation is yours. :-) Precisely: if you jump, both of you (you and the Earth) will move in direction of your (yours and Earths) common center of gravity. :-D This movement is proportional to the weights, so yours is BIIIIIIIIIIIIIG, Earths is unmeasureably small. And yes, thats why the common belief "heavier attracts lighter" (but once again, thats only the half of the truth).
shareEveryday interpretation? I was just using English people would understand. It's half the truth, as you say. The entire details may vary, but the result is the same, so I don't know why you need to be pedantic about it. Neither of us said anything completely false.
Anyway... I'm only watching this show because I can use my imagination and let this new dooms day version fill in the blanks. Gotta love the technology they're sporting in this one, and the honesty that yes.. of this were happening hundreds of other scientists would know about it at the same time.
You said I'm misleading, but I think the "heavier mass attracts lighter mass" sentence is misleading. If you stop here, someone can think that's all and the lighter mass doesn't do anything in the example.
But never mind, you're right, this is a good/bad (choose one) movie and NOT the physics class. I never wanted to hurt you with my opinion.
Regards,
Peter
You're both right. The writers did seem to be playing rather fast and loose with the notion of an interaction between the gravitational force and the electromagnetic force.
I am finding that the quantity of English needed to express this properly at a level commensurate with the (perceived) language level of the (average) Message Board User (for whom English may not be a first language) could result in a rather lengthy explanation.
g ~ Mm/d²
(Sorry, this character-set doesn't include subscripts.)
In most cases experienced on Earth, the Earth's mass is so enormously greater than anything an individual person can manipulate that the Earth's proportional reaction is immeasurably small.
The idea of being able to magnetize the Moon's core so as to expel the foreign object (whatever it was) is purest nonsense — but so is the original premise of the movie: that something could hit the Moon with enough force to change its orbit without smashing it into little bitty pieces parts.
I pointed out a few other things on the thread titled "What exactly Will Life Be Without a Moon- Won't We Still Get Wiped Out?"
The amount of real science in this movie is not enough to make you blink if it were to fly in your eye. Given a choice between this "science" and Lewis Carroll, I'll follow Alice and her white rabbit any day.
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All I can say to the writers, director(s) and producer(s) is:
I admire your ability to get paid for this.
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"The time has come," the Walrus said, "To talk of many things,"
Of atoms, stars and nebulæ, of entropy and genes;
And whether one can bend space;
And why the spaceship shrinks.
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[deleted]
They also made reference to the famous "levitating frog" experiments, which used extreme magnetism to counteract gravity. Of course you can defeat gravity with magnetism every day with refrigerator magnets, but that usually only works with metallic, magnetized objects. Now we know that magnetism can be used to counteract gravity's effect on ANYTHING.
I was under the impression that the film was combining and/or conflating the moon/star's gravity and extreme magnetism, then using the "very large version" of the levitation machine to magnetize the moon's core. So much of the movie was bogus, but I kinda liked that they referenced the new, very real levitation experiment and basically combined that with fantasy-science.
The Doctor is out. Far out.
I don't know if anyone has floated a frog before but magnets actually repel organic matter. Although you will only notice that if you have a VERY strong magnetic field concentrated in a VERY small space. I believe only one magnet exists in the world that can do that.
And gravity and electromagnetism are or rather were part of the same force. Right after the big bang all forces were combined into a super force, though it didn't even last a second though. And string theory hopes to explain all forces at once.
Magnets lift things, YAWN. Certainly not news. And yet there is another "take" on magnets.
Since the 1950's, one of the displays the University of Illinois has used during their annual Engineering Open House is the "flying frying pan".
Using several concentric electromagnets and 3-phase AC, they create a bowl shaped magnetic field, and place a 12-inch cast iron skillet in that magnetic field. It 'floats' about a foot above the electromagnets, and if shoved, moves, but quickly settles in place again.
BTW, the magnetic fields also cause the frying pan to heat up, and bacon and eggs have been cooked in the pan while it 'floats in mid-air'. (Think induction stove tops that only heat the (metal!) cooking pans; same idea.)
I'll try.
(nota bene: I'm going to use "iron" as a generic term for any ferrous metal; iron, steel, the nickel-iron cores of Earth and Moon, etc.)
Electromagnets are made by winding coils of wire around a bar of iron, and then passing an electric current through the wire. This current has to be DC like that out of a battery, not AC like that out of a wall outlet or your car's alternator. The strength of the magnetic field this creates depends on both the number of turns of wire around the iron bar and the power of the electric current through the wire.
Note: You can build an electromagnet without an iron core by wrapping coils of wire around any hollow tube, but it won't be nearly as strong as one with an iron core.
Please note that the wire has to wind around the bar. You can't magnetize anything by attaching one end of a wire to it and the other end of the wire to an electric power source. The process depends on an electric current — and without a closed circuit you have no current flowing.
Now: Given the level of the world's space programs (as stated in the movie), I don't think we could ship enough wire up to the Moon — in the time available — to make even one turn around the Moon's iron core, let alone drill the necessary channel for it so that the astronauts didn't have to wrap that wire around the entire Moon.
Also: Nothing they could have taken into space with them could generate the necessary power to push a current through that much wire — let alone create a magnetic field strong enough to repel that super-dense chunk of meteorite. Besides: They never established that the chunk of meteorite was magnetic, in the first place.
One more thing: All magnets have two poles: a magnetic North and a magnetic South. (The names derive from the magnetic compass.) While a sufficiently strong magnet might have repelled one end of that meteorite, it would have attracted the other end just as strongly. — As someone once said, "The books gotta balance!"
And that's why I said that the idea was nonsense.
Good science fiction is allowed one departure from known science. All the rest has to be logical extensions of known science and that one departure. This movie was getting so far afield I was beginning to think it was one of those "Sci-Fi Channel Original Movies" — quelle fromage!
That's why I've been saying that the amount of real science in this movie wasn't enough to make you blink if it were to fly in your eye.
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And that's why I say to the writer(s), director(s) and producer(s):
I admire your ability to get paid for this.
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"They stated VERY CLEARLY in the film that electromagnetism and gravity are different forces"
And then proceeded to treat them as if they were the same.
"It's easy enough to say that a concept in a film is nonsense, but how about you back it up?"
For every action there is an equal and opposite reaction. If the moon is "pushing out" an object, that object will also be pushing on the moon. Since the object in this case weighs about 160 times as much as the moon, what do you think will happen?
Instead of launching the "brown dwarf" into the sun, they would have launched the moon into the earth.
"...but so is the original premise of the movie: that something could hit the Moon with enough force to change its orbit without smashing it into little bitty pieces parts. "
From what I understood, Dr. Rhodes had originally mentioned this as the reason that the moon was now 30,000KM closer to the Earth, but was wrong. It was not the impact that "moved" the moon, rather it was the pull from the embedded brown dwarf.
But it could not have been a piece of a brown dwarf star that hit the Moon. As someone pointed out on another thread, the weight/mass they claimed for that chunk — at the density of brown dwarf material — would have made for a volume of matter larger than the Moon.
Also, they were misusing the term "brown dwarf". As someone else pointed out on that same thread, a "brown dwarf" is a body midway in size between a giant planet and dwarf star. Basically, it's a sub-dwarf star that didn't collect quite enough matter to ignite nuclear fusion.
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All I can say to the writers, director(s) and producer(s) is:
I admire your ability to get paid for this.
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What a wonderful series to make fun of! People, trains and ships floating at unpredictable intervals. But the crowning achievement was when you could see the moon in two pieces with debris floating around it, and the experts telling the administration that the orbit "is stable" and it's the end of the story.
shareMoon has a extremely small electromagnetic field. it is so negligible most pepel dont even *beep* it in. However the field here was nto caused by the moon, but rather by the brown dwarf latched intisde the moon.
Mass attract mass. higher mass attrract lighter mass stronger than the light one attrack earth. The force betweeen moonand earth is the same force, its not two different forces, both of them are pulling the masses t eachother. other forces keep them from crashing, but those are not gravity. earth does pull moon stronger, hence the moon is the one orbiting. if the frce was equal, the only equalibrium we could get would be orbiting eachother (sort of like how dual-stars work)
Yes, a brown dwarf would run thugh moon an earth an wouldnt even blink. but this was not a brown dwarf. this was a small fragment of a brown dwarf that has collided with something long ago and traveled though space to reach solar system.
If you take a small fragment of brown dwarf it coudl theoretically be stuc isnide themoon. however the frament would really be way smaller than deicted in the movie, more closer to the size of the piece they found on earth at the begining of the movie.
People are of curse correct about the fact that piece of brown dwarf would NOT be riding behind other asteroids.
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Applied Science? All science is applied. Eventually.