How does a laser gyroscope change the way changes in Earth’s rotation are measured?

a Accurate knowledge of The Earth’s instantaneous rotation speed necessary for Navigation and geolocation precise. the Fluctuations Throughout the day it is caused by The exchange of momentum between Earth’s fluids, That’s by saying, Atmosphere, hydrosphere, cryosphere and solid part.

Since many different Autonomous and globally distributed mass transit phenomena, The resulting effect on rotation It is unpredictable and must be measured on an ongoing basis. Now the team Scientists A. has developed A new way to measure He mentioned this in his article published in the magazine Nature photonics. There the team explains How your new approach works and how well it works when tested.

For many years, scientists have tried Improving accurate measurements of Earth’s rotation to Describe more clearly the length of a particular day. What makes matters more complicated is the length of the given day It depends on many factorsas Moon clouds, ocean currents, and wind direction.

Previous efforts to measure day length involved the use of radio telescopes or signals sent from several Earth-based facilities. More recently, Earth-orbiting satellites have been used, which has increased accuracy. In this new effort, the researchers tried a new approach: using a gyroscope.

This new tool, gyroscopewhich is simply called “G”, is headquartered in German Wetzel Geodetic Observatory. It is manufactured using a 16 meter laser cavity, making it a type of ring. Inside, two laser beams moving in opposite directions interact, creating an interference pattern.

The system works because a laser moving in the same direction as the Earth is more stretched than a laser moving in the opposite direction.

Then, as the Earth rotates, fluctuations in its speed are reflected in changes expressed in the interference pattern. From this, researchers were able to calculate the amount of distance traveled by a certain point on Earth during a certain period. Repeating the exercise over several days gave them the ability to calculate variations over time, allowing them to measure the length of a given day with an accuracy of just a few milliseconds over four months.

In our paper, we report monitoring minute changes in the Earth’s rotation speed at the level of five parts per billion, that is, with an accuracy of a few milliseconds, over 120 days of continuous measurements. We use an inertial measurement technique based on an optical ring laser interferometer rigidly attached to the Earth’s crust and operated in the Sagnac configuration.

The researchers concluded by suggesting that their method of measuring day length, as well as its variations, could be used to build better geophysical models, which could be used for global transport.

This wide-field gyroscope integrates more than three clocks per data point, in contrast to an entire global network of very long baseline interferometry and navigation satellite system receivers that can provide only one measurement per day.

* K. Ulrich Schreiber, First author of the study; A professional from the Satellite Geodesy Research Unit of the Technical University of Munich in Germany