# Traveling to Mars and time dilation

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If/when we go to Mars how will we deal with time dilation due to the gravitational differences between the two planets?

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PeterDonis
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The time dilation difference is too small to matter for most activities. For example, we have had unmanned spacecraft on Mars for several decades and the time dilation difference has never been an issue. If we wanted to set up GPS satellites orbiting Mars, then we would have to take the difference into account for the "Mars GPS" system to work correctly, yes.

The Wikipedia page on gravitational time dilation gives a good overview (although not perfect, it is Wikipedia), including the mathematical formulas for calculating the time dilation factor for someone standing on the surface of a non-rotating planet (which is still a pretty good approximation for Earth and Mars) and someone in a circular orbit about a planet.

https://en.wikipedia.org/wiki/Gravitational_time_dilation

Thank you, reading up on this now.

We humans are very adaptable. We have always found a way to make the environment fit us. The long trek to Mars is possible and then when we get there, we will have gravity. As I heard a quote in a movie once, "life finds a way".

If/when we go to Mars how will we deal with time dilation due to the gravitational differences between the two planets?
Significant time dilation occurs in two possible situations.
1, If two objects (including observers of course) are moving relative to each other at close to light speed.
2. An object which is deep inside a very large gravity well is being observed from outside of the gravity well.
The first does not apply at all, and while the second one technically does apply, the gravity of Earth or Mars is not enough to lead to any time dilation that would be noticeable by a human, it's in the region of a few picoseconds in an hour.
As PeterDonis pointed out though, it's enough to be significant where extreme timing precision is needed, as in GPS.

Craftek_Ana