Is it true that if everyone in the world jumped at the same time, the Earth would be thrown off its axis?

Question

Would our planet go spinning off into oblivion?

It is a question that has troubled me for years.....

Answer 1

No, not even if the jumpers were all jumping on one side of the earth and not the other.

The momentum imparted to the earth will be equal and opposite to that imparted to the jumpers as they leap into the air.

Then both the earth and the jumpers will be attracted back together by their mutual gravitational force.

Net result; The earth will shift very slightly in its orbit and then shift back again (actually as the earth is in fact a big blob of molten lava with a thin solidified crust, the earth will just deform slightly, but this will shift its centre of gravity a little, temporarily)

The energy expended in the jump will go somewhere. It is possible that it may cause a slight change in the earth's angular momentum, such that the length of the day is altered by a tiny, tiny amount (less than a nanosecond is my guess, using the effects of the asian tsunami quake as a ballpark)

If the jump is very tightly coordinated so that the energy is delivered as a very coherent impulse, there is a possibility it will cause earthquakes and tsunamis as tectonic plate boundaries under stress get 'woken up'.

Answer 2

No, not at all. First of all, everyone on the world jumped at once, all of the effects would be distributed around the entire globe in opposing directions, cancelling themselves out. But even if everybody went to, say, the North Pole and jumped, the effects would be minimal. There are about 6 billion people in the world. Let's say that each person weighs an average of 100 kg. I'll bet the average weight is less, but I'm being conservative. That means that people have a total mass of 600 billion kg, or 6 x 10^11 kg. The Earth has a mass of 6 x 10^24 kg. The mass of people is inconsequential compared to the mass of the planet as a whole, and a displacement of that mass by less than a meter is not going to mean diddly squat for a planet with a radius of over 6000 km. We're talking about moving 0.00000000001% of the Earth's mass by less than .000016% of its radius. I'm not concerned.

Answer 3

Well, you can relax now because I can tell you
with no doubt whatsoever that you will never get
all the people on this Earth to do anything together
at the same time.

Reasons:

We all speak different languages.
We all have different cultures , societies, educations, and priorities.
We live in a multitude of different time zones.
Daytime here may be nightime somewhere else.

Then, if we were to get down to the bold faced reality
of the issue, our combined weight is so widely
distributed across the face of the earth that it would
not make the slightest bit of difference nif we all lay
down or jumped up and down.

But, if we all planted a tree today, we might stop
Global Warming.

Answer 4

If not for the simple fact that those people jumping in one hemisphere might well cancel out those jumping in the other hemisphere. But of course its an impossibility anyway because a) the wold populous would never agree to mass suicide and b) try getting everybody at exactly the same time to do that? Sleep well oh challenged one.

Answer 5

That wouldn't happen. First because of the huge rotational inertia of the Earth going around the Sun is so strong. Also, doing something like this would require everyone working together...and we all know the world isn't that good at working together :)

Also, people do not jump really high, so the "potential energy" of their jump isn't as great as a huge asteroid smashing us.

Answer 6

No, there are people all around the world. If they all jumped, the ones on the Southern Hemisphere would counteract the ones on the Northern Hemisphere. Besides, the centre of gravity is in the centre of the Earth, so you couldn't knock it off course by jumping on it.

There's not nearly enough biomass on the Earth to knock it off course anyway.

Answer 7

Now you may relax, as we are not heavier than Earth, and we are at North South East West, means we will be pressing against each other if we happen to jump all together at the same time. Still, we should try it some day to satisfy your curiosity.
You had your fun, haha.

Answer 8

No for several reasons....including

populations are fairly evenly spread around the globe..

initial force of jumping up would be countered by landing, i.e. same force but opposite directions

mass of the earth is so great we would even create much of a tremor

Answer 9

Nope. Even if you can keep half the canarys flying, the total mass and distribution will remain the same in the earth's gravitational field. It could Never happen.

Answer 10

Never, the total mass of every human and animal on earth is insignificant compared to the mass of the earth.