Neil deGrasse Tyson Explains How Time Is Different on Mars

Is there any time dilation on Mars? Neil deGrasse Tyson explains how Albert Einstein’s theory of general relativity can make time go faster depending on your relative speed and gravity. As you move faster in space, time goes slower. As seen in the movie, "Interstellar," Earth’s surface has a higher gravity than the Martian surface, so on Mars you will experience your seconds slightly faster than people on Earth. Plus, as Neil explains to co-host Chuck Nice, because GPS satellites experience less gravity in orbit around Earth than their time-keeping counterparts on Earth’s surface, engineers have to compensate for that difference in time so they don’t run fast.

Follow StarTalk:

About StarTalk:
Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up!

#StarTalk #NeildeGrasseTyson

[patrickroelant]

I wish they would post more full podcasts, because i find them interesting and love listening to them while doing stuff.

[Atouk]

Chuck has the best job ever. He gets to hang with NDT, and have his mind blown every time. I just feel humbled that I have a free, front row seat to all of it!

[secondghost]

I came back from a black hole in space once. The trick to success is dividing by zero.

[Incred_Canemian]

I remember my trip to Mars. Whiplash like you wouldn't believe!

[parthparthparth]

Why does Chuck use his phone to check the time if he is wearing a watch?

[chrisp]

from my understanding: time dilation depends on velocity and gravitational field strength. The faster something travels the slower time is and the more gravity an object has the slower time is. Mars has about 1/3 of earth gravity, so time would run faster. Also, because mar is further away from the sun then earth it travels at slower velocity in order to maintain a stable orbit around the sun. This would make time run even faster on mars. In addition mars experience less of the sun's gravitational field then earth, so yet again it would make time go faster on mars.

But I don't think these factors would add up to much.

[ffggddss]

Very good. But a couple of fine points to clarify things a bit.
1. It isn't the actual acceleration of gravity that determines the time dilation factor, it's how deep you are in the potential well.
So while the strength of gravity on Mars' surface is ⅜ what it is on Earth's surface, the potential depth is only about ⅕ of Earth's.
2. There's also a difference in time-rates due to being higher in the Sun's potential well when you're on Mars. In fact, this difference is substantially greater than that due to the planetary potential wells.
So Mars gets faster clocks than Earth on both counts. But it's still only a few seconds or less over an entire human lifetime.

[jcoronet]

what about the speed of mars as compared to earth?

[anthaaraathmii]

I love that Forget It
.. and Of course Neil Sir. I love your way of thinking

From INDIA🇮🇳🇮🇳🇮🇳

[Xunkun]

'Kay, so, for those wondering _why_ it works, to go really fast or to be in heavy gravity:
SO, what're you doing with increased speed? You're putting more energy into the system, into whatever propulsion system there is.
What're you doing with increased gravity? You're increasing the mass.

Sound familiar? e=mc^2
So, since mass/matter is also energy, adding them is "same difference." Either way, you're increasing that thing's effect on Spacetime (and I think there are some PBS Spacetime vids that can explain this better, about how an object can weigh more than the sum of it's parts, due to having more potential energy in it, therefore more mass, without changing the amount of physical baryonic matter).

So, 1) whenever you saw spacetime represented as a big grid that gets distorted 'under' a heavy object like a star or a planet or Pat's mom: adding energy to increase the speed has the same effect as adding mass. and 2) since time and space are the same thing: the grid itself.

To keep it simple, imaging the scale it's using, and just call it "one unit of space, squared" to make a bunch of squares, natch. Gravity distorts it, so what "one unit of space' _means_ is stretched out. And as mentioned, spacetime, same thing in different directions, so you can think of those squares as also a measure of "one unit of _time, _ squared"--- and there you go, you can see the effect of increased speed on time, on the same thing as increased weight on space, and how all the terms are interchangeable.

It's 4AM so I don't know how well I worded that. Feel free to ask questions if I wasn't clear enough, others feel free to jump in with clarifications.

It's also why accelerating to meet or exceed the speed of light is (conventionally) impossible: because once you get to near-light speeds, you've been putting so much energy into a system, that you're also increasing it's mass. Ergo, it's heavier, so it'd take more energy to accelerate it. Ergo, you increase it's mass again. Loop that, and there you go.

[hrgwea]

What about the fact that Mars moves slower than Earth?
Does that have an effect on time?

[richardcornale]

If a black hole does not allow light to escape why then can jets of energy eminate from a black hole which has consumed a lot of mass and the jets of energy are traveling at less than the speed of light.

[dragoneslayer]

what about the difference between the largest possible terrestrial body that could possibly hold and atmosphere and the smallest possible terrestrial body that could hold an atmosphere?

[allenbonusOFC]

Q1: is a black hole like a giant magnetic in a flush manner. And if so what is at the end of it.. and for ex: something survives it where when what and how does it end?

[rgaud]

What would happen to radio transmissions near a black hole? If you are near a black hole and sending a message to someone else away from it, would your speech sound like it's stretched out and prolonged?

[madiescandon]

hi i have a question. Ever since i little ive always had an interest in the universe. I want to be an astronomer. my question is what is the difference between astrophysicist and astronomer. also, I would love to be an astronaut. I was thinking with astronomy, it could help me get in as an astronaut but looking at the requirements at NASA and it says that they look for people in a higher level in degree for engineering, biological science, physical science, or mathematics. in order for me to become an astronaut, should i consider these, will astronomy help me get in or no?

[lasredchris]

Particle accelerator
Time dilation - live more slowly than others
Reduced gravity

[cryvsspy]

So about the GPS satellites.... the reduced gravity they experience makes their clocks tick faster relative to us, but their high speeds make them tick slower. How strong are the two influences and is the net result faster or slower time passage?

[SelfReflective]

This is what I don't understand; if time is relative, what does it mean to say that some star, or system, or galaxy out there is xx billions of years old? Whose years, Earth years or their own time?

[sysprog]

What is "pre-correct?" Is that like traveling back in time before the mistake was made? Sounds like something from The Minority Report.