ISRO is set to initiate the replacement of navigational satellite with the launch of new IRNSS-1H (Indian Regional Navigation Satellite System) satellite. The new satellite boasts much-improved version of atomic clocks which ensure correctness of time and will improve synchronization of equipment on Earth.
As per the ISRO officials, the satellite weighing 1,425 kg will be launched using India’s most reliable rocket Polar Satellite Launch Vehicle (PSLV) on Thursday at 7 pm from Satish Dhawan Space Centre, SHAR, Sriharikota. This will be the eighth version of IRNSS satellite that will replace IRNSS-1A after the failure of atomic clocks.
Atomic clocks are the most accurate clocks in the world and are used as primary standards for international time distribution services. They use an electron transition frequency in the microwave, optical, or ultraviolet region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element.
IRNSS 1A satellite was using rubidium-based atomic clocks that were imported from Europe at a whopping price of $4million euro. However, three Rubidium Atomic Frequency Standard (RAFS) clocks on the IRNSS 1A that was launched four years ago started malfunctioning. It is to be noticed that three other satellites of the European Galileo satellite system that we’re using same clocks also reported the similar problem where clocks failed to perform.
“Except for malfunctioning of the atomic clocks in IRNSS-1A, the other components are functioning perfectly and it is being used for satellite messaging. The failure of atomic clocks had no impact on the overall performance of NaVIC,” a scientist in Shar said.
Scientists are optimistic that the new clock installed on IRNSS-1H will function properly for the longer duration. A team of scientists are testing the new clocks thoroughly at the Satellite Application Centre before sending it to the orbit.
ISRO always installs multiple backup systems in case of failure of the primary system, said Dr K. Sivan, director of Isro’s Vikram Sarabhai Space Centre, Thiruvananthapuram. He further added, “every organisation providing navigation system makes it a point to have the number of backup satellites for uninterrupted service to the users. Isro has readied two more satellites as per original plan and one among them, IRNSS-1H, is being launched now.”
The new satellite will have three atomic clocks but only one will be used and other two clocks will be used after the malfunctioning of the primary clock.