Clocks tick sooner on Mars than they do on Earth, partly as a result of Mars experiences much less gravitational pull from the Solar. Now scientists have calculated simply how a lot sooner — 477 microseconds, on common.
SCOTT DETROW, HOST:
Right here on Earth, we take without any consideration the truth that my watch shows the identical time as all people else’s watch does, at the very least inside my time zone. And while you step again and give it some thought, it’s type of wonderful that the entire world can sync up our clocks like that. However it’s much more difficult to sync up a clock right here on Earth with, say, a clock on Mars. And that’s as a result of time passes in another way, relying on the place you’re within the universe, and relying on the gravitational subject you are in. Fortunately for us, physicists on the Nationwide Institute of Requirements and Know-how have completed the mathematics, so we do not have to, they usually have discovered simply how a lot sooner a clock ticks on Mars. Bijunath Patla is the coauthor of a paper all about that out this month in The Astronomical Journal and joins me now. Welcome to ALL THINGS CONSIDERED.
BIJUNATH PATLA: Thanks for having me on.
DETROW: Let’s simply get proper to it. How a lot sooner do clocks tick on Mars than Earth?
PATLA: The clocks on Earth on common will tick 477 microseconds per day sooner than clocks on Earth.
DETROW: How can I even start to consider a microsecond?
PATLA: It is a millionth of a second, and it is roughly the time it takes gentle to journey 300 meters.
DETROW: OK. So why is it? I imply, I typically perceive the ideas of why time is relative elsewhere, however why is it precisely {that a} clock goes to go sooner on Mars than Earth?
PATLA: So the gap from the solar of Mars is means larger than it’s on Earth. As you go farther out into the photo voltaic system, the gravitational pull of the solar decreases dramatically. And due to this fact, since Mars is farther out than the Earth, the gravitational pull of the solar is far lesser, and due to this fact, the clocks are going to tick sooner.
DETROW: So I believe Einstein’s principle of relativity is, like, a popular culture factor that folks at the very least know the phrase, if not the main points, the final concept that gravity impacts the passage of time. I am questioning, do these calculations that you’ve got been engaged on – do they add something to that dialog? Is there one thing new right here to consider and study extra about?
PATLA: This calculation gives a framework the place we will take a look at basic relativity inside the inside photo voltaic system as a result of there’s a basic consensus inside the group that quantum mechanics and basic relativity are incompatible. And this sort of clocks on completely different planets would permit us to place constraints on the constraints of basic relativity, or to examine whether or not is there any elementary connection between quantum mechanics and relativity.
DETROW: I discover this actually fascinating. I like Mars. I like the final thought of space-time. However is there a sensible use for this, or is that this one step in direction of one thing very sensible for the scientific group to have a greater sense of now that you just figured this out?
PATLA: The sensible side comes from, if you wish to translate the communication infrastructure that we now have on Earth to Mars, then we’ll must have the clocks synchronize fairly precisely. If you wish to have a number of robots and scale up the operation, then the robots have to speak to one another. And due to this fact, we’ll must have a distinct approach to talk. And that is the place the calculation comes into play if we’re envisioning to turning into an interplanetary species.
DETROW: That’s Bijunath Patla, a theoretical physicist on the Nationwide Institute of Requirements and Know-how. I do know that proper now, at the very least, we’re simply speaking Earth to Earth, however I loved the dialog. Thanks a lot.
PATLA: Thanks.
Copyright © 2025 NPR. All rights reserved. Go to our web site phrases of use and permissions pages at www.npr.org for additional info.
Accuracy and availability of NPR transcripts might range. Transcript textual content could also be revised to right errors or match updates to audio. Audio on npr.org could also be edited after its authentic broadcast or publication. The authoritative file of NPR’s programming is the audio file.
