The Moon still has well-kept secrets. But the way time passes in its atmosphere is no longer one. In a new study published in the Astronomical Journal, American scientists have exemplified Einstein's theory of relativity, reports EOS. Our notion of time is different on Earth and on the Moon. In theory, this is not surprising. Albert Einstein's thesis states that two people cannot experience time in the same way if they do not move in the same direction and at the same speed.
However, the Moon and the Earth do not have the same speed of rotation and revolution. Scientists therefore decided to test Albert Einstein's theory by comparing the time that passes on Earth and its lunar equivalent. “On the Moon, the clock hands do not tick the same way as on Earth”explains Bijunath Patla, a physicist at the National Institute of Standards and Technology (NIST) in Colorado.
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Differences in characteristics between the Earth and the Moon explain the time gap
The Moon rotates on its axis in 27.32 days – as much time as it takes to revolve around the Earth, which explains why we only see one of its faces – at a rate of 16 .7 km/h. The Earth rotates at nearly 1,600 km/h over 24 hours, recalls Futura Sciences. This drastic difference in speed slows down time on the Moon.
On the other hand, the Moon has another very special characteristic: gravity. Much lower on our satellite than on our own soil, it also has an effect on the perception of time. She makes it go by faster. “These two elements act in contradiction and this gives a difference of 56 microseconds per day”notes Bijunath Patla. These 0.000056 seconds ahead of the lunar clocks could have more effects than we think.
An essential discovery for the future of space exploration
On Earth and in our daily lives, 56 microseconds generally makes no difference. But when it comes to guiding missions in Space or communicating with potential astronauts on the Moon from Earth, they are important. Even more crucial, it is the navigation systems of ships and other rockets that will have to take this gap into account.
Current navigation systems work on the principle of clock synchronization, using radio waves, which travel at the speed of light – namely 299,792,458 m/s. In this extremely short time frame for humans, failing to take into account the 56 microsecond gap between the Earth and the Moon could have disastrous consequences for space navigation.
Physicists must now put this new knowledge into practice so that the systems can determine the exact position of objects projected into space, at any time.
