World Jump Day

Scientists from the ISA/Munchen (Germany) have published a report (interview excerpt, Prof. Hans Peter Niesward, June 23 2004) which confirms that planet eart could be driven out of its current orbital rotation by the combined force of human beings jumping. Pro, Hans Niesward and his colleagues at the Department of Gravitationsphyik estimated that it would take a minimum of 600 Million people on the western hemisphare to jump at the same moment.

The Scientist incorporated a variety of seismographic recordings ranging from impacts of comets (comet "Joulios" hitting the surface of the Pacific Ocean, 03 21 2001)


More info at www.worldjumpday.org


This is gonna be one huge fun events, too bad I didn't live in one of those Time Zone range...

No matter how exciting this sounds, its not in accordance with the fundamentals of nature.
well...its pretty simple...when you are jumping you are landing back on earth which means there is no net force to generate enough momentum to displace the earth travelling with an orbital velocity of 29.8km/s within those 1-2 seconds of the jump...unless you have those 600 million ppl jump across the earth's atmospheric boundary with a velocity greater than the terminal velocity, i think.

I want to know what other ppl think?

They gotta have some scientific proven to be able to get this far, I'm pretty sure they can do it... Just a matter of how many people are going to participate in this events... Btw I hate doing science, but I love it... Hmmm am I contradict myself? :stickout:

I don't know even if it were proven that I'd want to jump to move the earth out of rotation. I like Earth just where it is and I'd rather not stray off course. :)

Well if it only take us just 1 jump to reduce the global warming, why da hell not? I'm going for it...

It would be fun if the earth goes offcourse, and into the sun (apart from the massive heat). Or maybe colide into another planet. Woo hoo. :bounce: :bounce: :bounce:

Lolz now that is some scary ****... :bounce: :dead: :angel:

Ahhh yes this is technically possible using the formula Force = Mass x Acceleration. Lets say one person jumps at a weight of 45kilograms.
Force = 45kg x 9.8m/s (the acceleration due to gravity). So the force that is exerted on you is 441 newtons. Assuming newtons third law is correct. Which states that every action has an equal and opposite reaction. We can say 441 newtons= the mass of the earth x acceleration. or 441 newtons = (5.974 x 10^24 kg) x acceleration. Which means that the acceleration of 441 newtons on the earth is 7.3x 10^-23 m/s. Or 2 protons per second. Multiply this by 600 million and you almost have the earth off course by an entire atom!! Isn't science exciting?

Not posible - not even an atom.

The force exerted in jumping is equal to the force exerted on the earth by landing. As both forces operate in opposite directions, they cancel each other out (don't blame me, blame Newton).

It would be fun if the earth goes offcourse, and into the sun (apart from the massive heat). Or maybe colide into another planet. Woo hoo. :bounce: :bounce: :bounce:
what if D-O-G really spelled C-A-T ?

Hmmmmmmmmmmmm

who would win in a fight a three legged dog with a spear for a tail or a one eyed cat?

ahh, them scientists are full of s***, 6 billion people don't weigh enough to affect the earth.

There must be a thousand other variables. Like for example would all 600 million people have to be standing next to each other in like one big mass? Or 600mil anywhere within a large radius? What about altitute and thus different pressures? What about the material of earth? For example if someone jumps and lands on sand, that would be less force against earth then a person on concrete, where his weight is spread over a larger area.

I'm not very scientific, I don't know any fancy formulas, but picture this okay?

600 million people, all standing next to each other, at 0 altitute, on a hard surface of earth. Everyone jumped the same height and landed at the same time. Now how does an "impact" like that, compare to, say, a meteor hitting? Like what would the diameter be of 600 million people standing in a circle? Picture all those people as like a big hammer against earth.

What is interresting is, when two objects collide with equal force, they cancel each other out. This HAS to be, or else one object would always be pushing the other object to move. Also, if one object is stationary, and able to resist certain forces, it can't be moved. Like if you put both your hands together in front of you and push equally with both arms so that your hands stay still, this is equal force. But then walk up to a block wall and lean on it. If you're leaning 20 pounds against the wall, it is pushing 20 pounds back at you. If you push 150 pounds, it pushes 150 pounds. So until you push more then it can resist, it will stay still and neither of you will move. But if you push 1000 pounds, that wall may push over, and you don't cancel each other out anymore.

So then, what possible difference can ONE person do, jumping? And then multiply that by 600 million. The earth, by far, has enough resistance to cancel such force. Especially if the force is spread over so much space as "western hemisphere".

It is interresting to think about though :)

Especially if the force is spread over so much space as "western hemisphere".


A very good point..

when you jump, all of your kinetic energy is transfereed to whetever you're standing on, whether it be sand or concrete. if the material beneath your feet compresses/crushes it can absorb some or all of the hit. sand does not compress.

but whatever you stand on, wherever you are, the answer remains the same.

The total energy exerted on going upwards equals the total energy exerted when going downwards. It's simply newtonian physics.

Yes but what about the impact itself? I mean, if you jump and hit the ground with 400 pounds of force, surely it didn't take 400 pounds of force against the earth to get you up in the air. Or does it?

I does, though it's slightly more complicated if you look at it in fine detail as it will involve a variety of different forms of energy conversion etc, but when it's all added up, it comes out the same, as "every action has an equal and opposite reaction" :)

Imagine you weigh 200 pounds.

You would have to expend 200 pounds of force simply to stand on the ground. To get off into the air, lets say you require another 200 pounds of force, which would take you far enough into the air to land with 200 pounds of force plus your own weight of 200 pounds, and so it's 400 pounds from jumping to 400 pounds on landing.

Even if you were to climb on something (which would certainly complicate things!!!) the force used to climb is equal to additional force from hitting the floor again.

Of course, it goes into energy conversion from various forms to other various forms, gravitation, etc, etc, but essentially it works out the same due to equal and opposite reactions to whatever you do.

when you jump, all of your kinetic energy is transfereed to whetever you're standing on, whether it be sand or concrete. if the material beneath your feet compresses/crushes it can absorb some or all of the hit. sand does not compress.


After 20 odd years in the paving business, I can assure you that sand does, indeed, compress. Sand is crushed (or eroded) rock. Using a vibratory compacting device, and with the optimum moisture content (very low %) you can make sand quite stable, especially extremely fine sand (crusher dust). In fact, it can become almost as stable as the rock from whence it came.




witless is bliss

You would have to expend 200 pounds of force simply to stand on the ground. To get off into the air, lets say you require another 200 pounds of force, which would take you far enough into the air to land with 200 pounds of force plus your own weight of 200 pounds, and so it's 400 pounds from jumping to 400 pounds on landing.

by your logical then the actual jump its self would "expell" enough force to move the planet???? your reasoning is correct but the actual application of it is nonsense... too many variables..
its all complete b*llox IF if if if if..

....if your Aunt had balls she'd be your uncle...no offence like

What if 600 million people in the western hemisphere simultaneously farted, and 600 million people in the eastern hemisphere simultaneously LIT A MATCH??!!




witless is bliss

What if 600 million people in the western hemisphere simultaneously farted, and 600 million people in the eastern hemisphere simultaneously LIT A MATCH??!!

excellent point...taking into account Oprah Wimphrey's 18th law of thermo dymanic structual explosive methane law it would be possible to float the planet nearer to the sun so we all get better tans..sounds like a plan

sand will settle and what have you, but the grains retain thier mass and shape. railroad engineers will dump sand under the drive wheels of a train for traction because of this.

Sand that is not interfered with will settle, it's true. Sand under the massive weight of a locomotive becomes instant dust, thus proving a brief period of increased friction. Still- sand can be compressed. I would also posit that the grains plced under that train DO NOT retain individual mass and shape.

My my where this thread has gone!

How about this: Why don't they just go out in a desert someplace and set up 600 million impact machines. Then let all the machines slam the earch with far more force then a person jumping, could?

Or maybe, how about explosives? If the force exherted jumping is the same as that of landing, surely the force of an explosive against the earch doesn't equal the few pounds that make up the explosive. Assuming the force of the blast can be directed strait down.
Or suppose a bunch of rockets, flew up and then dropped tons upon tons of metal onto the earth. Being that it is dropped from the air, there is no opposing force of the object leaving; on top of gravity and acceleration, can surely hit the earth with as much force.

But then again, if the force of jumping equals the force of landing, wouldn't that just mean that the earth is being pushed twice? Once for jumping and once for landing? And with a second or two in between, that would turn the impact of 600 million people in to 1.2 billion impacts wouldn't it?

What if all 6 billion of us just gathered up in, say, the far east of Siberia. The combined mass in one spot would surely increase the planets' speed of rotation; then combined with the massive shivering effect, the already slight axial tilt would increase to the point that THE SUN WOULD RISE IN THE NORTH!! Every 18.4 hrs. (my math on that is a little fuzzy- not everyone weighs the same) What a wonderfully calamitous event. Perhaps if it were organized in time, it would make for a truly NEW year!



witless is bliss

What if all 6 billion of us ran in the same direction really fast would this cause the earth to spin in the opossite direction thus sending us back in time?

.....it worked for superman

If so, I'll hafta just watch. I'm old and can't run. Guess I'll just see you guys when you get back to my time. Or are you already back, and don't know you left? If you do go, when you get back, ALL the ice cream sandwiches in the world will be gone! BTW- visited the Jump Day site- absolutely NO expounding of scientific theory, but---they WILL sell you a T-shirt!!!!

We could pick you up on the way..then start running again..its not a bother

Okay, but someone's gotta carry my cooler, I ain't goin without the aforementioned ice cream sandwiches. Course, what with global warming and all, they'll probly melt. OH, WAIT!.. In the future, Jump Day will have fixed that pesky warming thing, so they'll be alright. Main problem as I see it: if you guys stop in Vegas to pick me up, a lot of the faithful might end up at the tables, and we'll only make it to next week or so.

if the earth was an apple, the skin would be the parts we know. it is so massive that even a trillion people jumping would make no diffrence.

lets just say that a person will not crush sand as in the original question...

What they need to do is get all the ****roaches to jump at once. There is more insect body mass on this planet than there is human, anyway. Get 'em all in one hemisphere, let 'em jump, then RAID 'em on their way down.

Even if earth could be moved, it would simply fall back into orbit. Nothing would change. But if we could change the mass of earth and it magnetic properties, perhaps blast 10% of earth into space, earth's mass may change enough to naturally fall in to a new orbit steadily.

You know what would really suck? What if everybody jumped, but instead of pushing earthy farther out, it just increased the speed of rotation? Days and nights would suddenly become shorter, and we'd have 600 days in a year, even though a year is the same length. Weird.

There is no such thing as time. Time was mearly invented to measure between events. If there were no events, would there be time?

PC is everywhere!! (politically correct, that is) Things are pretty tight when a guy gets bleeped for saying ****roaches. Next, it'll be on son-of-a-**n. Vigilante- as per my prev post, it'd be fun, though, wouldn't it, if we had those 600 sunsets in the south?

if we all burned massive fires day and night for the next 5 months we could increase global warming and maybe it wouldn't be so f**king cold and wet in ireland....

Is this "outwit the techspot board censor" day or something?

seriously though, any force landing on the planet that's enough to knock it into orbit would be enough to case an earthquake instead IMHO.

no but it would be hotter than the normal 105F in the summer here in El Paso..... :hotbounce

global warming would submerge ireland, as it would other regions of the world. interestingly enough, chicago's official elevation is 666 feet above sea level (hmmmmm.....) glaciers and whatnot would melt a bit and the released waters would raise the sea level and upset the currents (via salt concentrations)

And those Irish are just stubborn enough to keep living there ;)

The Irish are not stubborn, they are like we Germans - steadfast! He even offered to pick me up on his way to last week. A stubborn man would have kept on running, at least back to the age of chivalry, to throw down his gauntlet. ( While you're there, Irish, have 'em to get them fires goin!!!

And to Zephead: methinks Chicago's elevation might've lifted a bit after Ozzie's boys' feat! Ya think?

Not posible - not even an atom.

The force exerted in jumping is equal to the force exerted on the earth by landing. As both forces operate in opposite directions, they cancel each other out (don't blame me, blame Newton).


I think you (and Newton) are underestimating humanity as an individual force independent from the earth, its energy from human beings and energy from the earth. One person is insignificant but 600.000.000 its a huge mass hiting the earth... I belive it is possible :knock: but iīm not so sure about the consequences of such action and itīs ethical sense.

:) Fair enough. You are indeed entitled to your opinion, iven if it's one that isn't supported by the fundamental laws of physics.

laws are ment to be broken, donīt get so deep into what you read, free your mind and consider all the options :giddy:

I think you (and Newton) are underestimating humanity as an individual force independent from the earth, its energy from human beings and energy from the earth. One person is insignificant but 600.000.000 its a huge mass hiting the earth... I belive it is possible :knock: but iīm not so sure about the consequences of such action and itīs ethical sense.

If this were truly possible- seems like our rotational equilibrium would be wobbly due to the disproportionate number of bodies residing in China/India. Once this counterbalance reaches the inevitable stoppage of rotation, I just hope my side is facing the sun so I don't freeze to death. Also, toffeapple could put out his fires! :rolleyes:

If this thing were truly scientifically possible, every government on earth would be hopping on it like jackrabbits (no pun inteded) :)
Surely the governments and NASA and every other kind of scientist on earth would be all over trying to figure out how such a move would effect everything from the moon's orbit, to tides, to weather, to seismic activity, etc etc etc...

Since no credible agency seems interrested, it must not be within the realm of possibility. But buy up the T-shirts before they are gone!

But then again, if the force of jumping equals the force of landing, wouldn't that just mean that the earth is being pushed twice? Once for jumping and once for landing? And with a second or two in between, that would turn the impact of 600 million people in to 1.2 billion impacts wouldn't it?

Spike is right, but he didn't use the KEY words: Centre of Mass. Gravity is a conservation force, true. What goes up must come down. Unless what goes up moves at 7 miles/second or faster (escape velocity of Earth).
What would happen if 600Meg ppl jumped all at the same time ( consider the technical diffuclties in the statement "all at the same time"), would be a : CentreofMass= (M1R1 +m2R2)/M1+m2, where M1=Earth mass ,
R1=Radius of Earth in meters. m2 =Total ppl mass (of 600Meg ppl), R2 =R1+jump height. (1 meter assume for simple calculation). Ok now we would expand the equation to get M1(R1+r1) and m2(R1+r2), where r2=jump height of 1meter and solve for r1.

simplifying the equation we get. r1=(m2Xr2)/M1, if r2=1m, then r1=m2/M1 or the ratio of jumpingpeople mass/Earth mass. r1 becomes indeed very small!!

What would happen is you'd get a wobble of whatever r1 works out to be during the jump. Then some minor decaying oscillation after the landing. Is 600 million enough, NO.
Edit : Sun_Jupiter Ex: put Sun in position 0, mass = 333,000 Earths. Jupiter in position 778,000,000 km, mass=318 Earths. Center of mass is 742,000 km from the Sun center, 96,000 km outside its surface. As Jupiter does its 11 year orbit, the Sun does a 1.5 million km orbit around the center of mass.

EDIT: I NEED TO GET OUT MORE puke:

Maybe you do, but thankyou anway :D lol

seriously though, someone needs to be interested enough in these things to spend the time with such posts. why not you? lol.

Spike is right, but he didn't use the KEY words: Centre of Mass. Gravity is a conservation force, true. What goes up must come down. Unless what goes up moves at 7 miles/second or faster (escape velocity of Earth).
What would happen if 600Meg ppl jumped all at the same time ( consider the technical diffuclties in the statement "all at the same time"), would be a : CentreofMass= (M1R1 +m2R2)/M1+m2, where M1=Earth mass ,
R1=Radius of Earth in meters. m2 =Total ppl mass (of 600Meg ppl), R2 =R1+jump height. (1 meter assume for simple calculation). Ok now we would expand the equation to get M1(R1+r1) and m2(R1+r2), where r2=jump height of 1meter and solve for r1.

simplifying the equation we get. r1=(m2Xr2)/M1, if r2=1m, then r1=m2/M1 or the ratio of jumpingpeople mass/Earth mass. r1 becomes indeed very small!!

What would happen is you'd get a wobble of whatever r1 works out to be during the jump. Then some minor decaying oscillation after the landing. Is 600 million enough, NO.
Edit : Sun_Jupiter Ex: put Sun in position 0, mass = 333,000 Earths. Jupiter in position 778,000,000 km, mass=318 Earths. Center of mass is 742,000 km from the Sun center, 96,000 km outside its surface. As Jupiter does its 11 year orbit, the Sun does a 1.5 million km orbit around the center of mass.

EDIT: I NEED TO GET OUT MORE puke:
er...WHAT?

the earth simply has too much inertia (on account of it's mass) to be affected by humans jumping. i doubt there'e anything that we could do to alter the earth's position in it's orbit.

yeah very true.....but forget all that did someone say we Irish are like the germans??? did i hear that correctly?

frankly yiz have more chance of putting the earth on your back and jumping from planet to planet singing christmas carols than you have of getting an Irishman to admit he is like a german....not that theres anything wrong with being German there just NOthing like Irish people and I lived there for 4 months so im not stereotyping...

ok back to the physics.....as interesting as that is.....