For the first time, NIST physicists have calculated the exact rate of the Martian clock: on average, it will tick 477 microseconds faster than a day, but Mars' eccentric orbit and the influence of the Sun and neighboring planets can change this rate by up to 226 microseconds per day over the course of a Martian year.
According to NIST, a Martian day is 40 minutes longer than an Earth's, and the year lasts 687 days. Scientists note that it is important to know not only the length of the day, but also the accuracy of each second in comparison with the Earth.
“If you landed on the surface of Mars with an atomic clock, it would still tick the same way as on Earth. But if you compare the Martian clock with the Earth's, they will be out of sync. The problem is to determine how much Martian time is offset from Earth's, much like calculating the difference in time zones,” NIST informs.
Physicists chose a point on the Martian surface as a reference point, an analogue of the sea level at the Earth's equator. Thanks to years of data from Mars missions, it has been possible to estimate Mars' gravity to be five times weaker than Earth's.
But, as scientists noted, it was necessary to take into account not only the gravity of the planet. The Sun makes up more than 99% of the mass of the Solar System, and Mars is influenced by the Earth, Moon, Jupiter and Saturn. This forms its eccentric orbit, which has a significant effect on timing.
NIST noted that although 477 microseconds seems small, it is critical for precision communications networks. Currently, communications between Earth and Mars are delayed by 4–24 minutes. This is reminiscent of pre-telegram communication, when people sent handwritten letters by sea and waited weeks or months for a response, the scientists pointed out.
The introduction of a system for accurately determining time between planets opens the way to the creation of synchronized networks over vast distances. According to NIST physicist Bijunath Patla, scientists are now closer to realizing the idea of expanding the solar system, which was previously only written about in science fiction.
Patla noted that if you get synchronization, it will be almost like real time without losing information. He added that knowing the exact passage of time on Mars not only helps in preparation for future missions, but also deepens scientific understanding of Einstein's theories of relativity.
