Their orbital velocity, about 7700 metres per second, is only 0.0000257 times the speed of light, yielding a time dilation factor of 1.00000000033; each second on board Mir, 1.00000000033 seconds pass on Earth. For every second you age on Earth, the cosmonaut in orbit ages 3 nanoseconds less. This doesn’t seem like much, but it adds up; after a year the cosmonaut’s watch will be 3.8 seconds behind your earthbound timepiece.17,500 mph the spacestation travels around the earth.I could make rocket time machine.That is my name for it.You could put a bunch of objects with the same speeds on top of each other that push up each other to add up to 17,500 mph.Make two of these rows and then start the second row after 3.8 seconds pass.Then you could go into the future a total of 7.6 second.You could repeat that process over and over again for greater effect.
There is an additional time calculation you left out. The further one moves away from a gravity source, the quicker time will transpire.
Time tunnel, you would also be a very long way away physically just to grab a few minutes time dilation over the whole journey: is it worth it?
Vodkafan what do you mean by that ?Einstein i never heard of that before.
Well if you are adding propulsion elements to make it go faster there are limits…it won’t stay in orbit it will break out of orbit and shoot off into space…you could make it go on a bigger orbit (of the whole solar system perhaps) and return but that would take a lot of years…the ship would have to be provisioned for that length of time, you are basically and primarily a space traveller not a time traveller..
I could redesign the device to be a spiral.That way it would take up less space.There are other designs i am considering.Anyway a years time lenght could start within another years time lenght.Do you understand what i am getting at.For every year
there would be 3.8 seconds added.It all depends on the time when i start each spiral row of speeding objects.
Apologies, not really getting it time tunnel . If they are separate objects running at the same time (or staggered even)they will each make 3.8 seconds yes but you can’t add those 3.8 seconds together? They will be the same 3.8 seconds shared. I misunderstood I thought you were talking about some sort of craft with a cosmonaut (chrononaut!) inside.
And yes, what Einstein was saying is true. It is gravity (curvature of space time) that slows time down. Time gets thick and heavy and slow down here and thin and zippy out in space. But it’s all relative, depending on were you are observing from, accelerating, decelerating, whatever.
They don’t run at the same time one will run 3.8 seconds later than the other.To gain 3.8 seconds more in time or slightly less.Can we agree that a years time is a years time no matter where you start in that year.Like if you started from january 1,2014.It would be a year from that time.If you started on june 1,2014.It would be year from that time.
Let’s go back to your original post. I assume we are still talking about a spacecraft with a man inside it orbiting the Earth. There is a slight time dilation effect, 3.8 seconds in a year. You want to increase it’s speed drastically to increase the time dilation effect.
First off, there are physical reasons you can’t increase the speed a whole lot. An orbit is the result of two forces; gravity of the Earth pulling it down and it’s speed which stops it falling. There is a relationship, a balance between these two that keeps it where it is.
Imagine you have a tennis ball on a thin string and you are swinging it around your head. You are the Earth, the ball is the ship and the string is gravity. You are swinging it hard enough to make a nice circle. The ball wants to escape; you can feel it. Now you start swinging it much faster and harder. The increased force overcomes the strength of the string; it breaks. The ball flies off into space.
Exactly the same will happen if you increase the speed of your space ship. It will escape the gravity and break orbit and fly off into space (but as Einstein says, it will enjoy even better time dilation effects out there)
But lets for the sake of argument ignore all that and say that you CAN increase the speed and stay in the same orbit . Let’s increase the speed by 100 x, an incredible amount. The time dilation becomes 380 seconds, or getting on for 6 and 1/2 minutes. The astronaut will be six and a half minutes younger than he would be if he had stayed on Earth.
But he hasn’t done anything: he has sat in a tin can for a year looking out the window. He hasn’t travelled in time per se.
I am not talking about a spaceship.I am taking about a machine on the earth.
According to einstien theory of relativity if a person goes the speed of light time would pass by faster for people on earth.Than a person on a spaceship that is going the speed of light.I believe that applies to low speeds as well but in smaller increments.
The time dilation is not linear with an increase in speed. Most of the slowing down of time occurs at significant velocities closer to light speed.
Actually if you manage to escape earths gravity, time will speed up. The earths gravity field will no longer be present to contribute to the time dilation effect it has on us down here.
OK got it. But you would have REAL problems there. The Earth is moving around the sun at 108,000 km/h and on top of that it is spinning on its axis at 1670 km/h . These speeds are a fraction of the speed of light (at 299 792.458 km **per second! **). So if you somehow managed to get even half way to the speed of light, within a second your machine would no longer be anywhere near Earth it will have ripped itself off the planet and be 150 million km away.
Thanks Einstein I didn’t know that. 
I am not talking about going the speed of light in relation to my mchine.I am talking about time travel using evderyday speeds.If you do not get it reread everything i wrote and think it over or do you want me to spell it out for you.
Ah now I am making you mad, which was not my intention. I am tired so I will leave it for now. I must be completely misunderstanding you. Any further explanation you want to put, yes please do.
Einstein what make you think that time dilation does not increase with speed.How else would it increase as a object gets closer to the speed of light.What are you saying really?I may not accept it but you can try.
Can I ask potentially stupid question?
What is light speed? It it 3*10 ^8mtrs /s? As in it does not matter if it is a photon or a space ship. It must travel that many metres per second.
Or, is it the speed of the photon itself. Therefore if the photon was only moving at 1 mtr /s and you passed it travelling at 2mtrs /s then you are travelling twice the speed of light…
If that makes any sense at all…
It is the speed of the photon itself.
It does increase with speed. But the increase in time dilation is very small compared to speed under say half light speed.
I just wanted to point out that the gravity field of the earth, produces more time dilation than any publicly known about, man made spacecraft, will ever achieve.
In order to offset the absence of gravity time dilation, a spacecraft would probably have to travel faster than half the speed of light.
Remember most of the orbital calculations are for spacecraft relatively close to earth. So a very high orbit spacecraft might actually have time dilation in reverse. And the occupants could come back slightly older than us here on earth.