ISRO atomic clock

After ISRO soon launched its Indian Regional Navigation Satellite System (IRNSS-1A) in the year 2016, it encountered with a problem with its rubidium atomic clock which was aboard in the satellite. This situation further aggravated the position of ISRO when the other two clocks also became unserviceable. The ISRO team failed to repair the clocks as they were all of the European technology whose functionality was not in accordance with that of ISRO’s. Repeated malfunctioning of these atomic clocks has acted as a hindrance to ISRO’s efforts to set up regional GPS, making them lag behind in their inventions and discoveries in the desired field. Something had to be done to get rid of these technological faults and so ISRO came up with a solution based on their own intelligence and expertise.

The solution was to have their self-built atomic clock so that they have complete control over its functionality. Space Applications Center (SAC) has made an indigenous atomic clock that is undergoing a series of tests for regulating its accuracy and durability in space. Once it clears these basic tests, it will be used in the experimental navigation of satellites. But one may feel why these specifically made atomic clocks are necessary for these satellites? Well, the answer lies below:


The accuracy of a satellite navigation system highly depends on the exact synchronization of these clocks. Even a difference of in a microsecond can lead to a positioning error amounting to 300 meters. The perfect synchronization fraction must be within 1/100 of a microsecond. These satellite clocks should have such good functionality that can work without having the need to adjust them for 12 hours. The perfect accuracy needed by these clocks is 1 second over 140,000 years.

The telecommunication system of the earth relies on these atomic clocks. While making a call or sending data across a network, our information traverses the path of different networks. This information is sent in packets and then comes to the receiver in an assimilated and understandable form. These networks need to function at a uniform speed to avoid the loss of data or congestion of the data highways. This speed is 1 second over 3000 years and can only be met by atomic clocks.


The fact that we no longer measure time-based on the movement of the earth is proof that atomic clocks have changed this viewpoint that has been held true since ages. The time is measured against the movement of the cesium-133 atom. Presently the only connection that time has with the average rotation of the Earth is the addition of a leap second that is done so occasionally in order to indemnify the slow rotational movement of the earth. It is here that the atomic clocks are expected to offer the greatest accuracy and stability over time.

Therefore the innovation of ISRO’s own atomic clock has made them acquire one of the few positions that not many space organizations have built by using their advanced methods of technology. Their invention will not only help in India’s development but will also make them acquire a position of prominence in the space world.

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