This is in continuation of Time Travel.

In the previous post, I explained the consequences of using a time machine. However, there's a bigger problem than that. The machine can only travel in time, not space.

Which means, even if we travel in time, we will be on the same spot in space. Therefore, our initial position (from where we travel in time) and our final position (where we arrive after traveling in time) will be different. How different?


The Earth rotates from west to east.

The equatorial circumference of the Earth is 40,075 km. (Source)

That means, if we're on the equator, we travel 40,075 km (in space) every day, just because of the rotation of the Earth. (From this point forward, let's assume the person who is going to travel in time does so on the equator.)

Number of minutes in one hour is 60, and number of hours in a day is 24. So, in a minute, (if at the equator) we travel x km.

x = 40,075 / 24 * 60
x = 40,075 / 1440
x = 28 (approximate value)

So, if the person travels one minute in the past, he will be 28 km west of his initial position (because the Earth rotates from west to east)

But wait. That's just the tip of the iceberg. Not only does the Earth rotate continuously, it also revolves around the sun.



The circumference of Earth's orbit around the sun is 940,000,000 km (940 million) (Source)

The Earth covers this distance in 365.25 days. (Source)

So, in a minute, the Earth travels y km.

y = 940,000,000 / 365.25 x 1440
y = 940,000,000 / 525960
y = 1787 (approximate value)

Put it all together and, in 1 minute, if your position in space remains constant,



where,


So, to overcome this problem, the time machine would also have to travel in space. Therefore, a time machine would also have to possess the ability to teleport us.