Atomic clocks on navigation satellites by Isro and ESA are failing, and nobody has an explanation

10 atomic clocks on board the Galileo navigation satellite constellation by the European Space Agency (ESA) have failed. Navigation satellites require highly precise clocks, which are instrumental in providing precise information about co-ordinates on the ground. The clocks conked off mysteriously, with no known explanation.Co-incidentally, over a period of six months, three of the rubidium timekeepers on board the IRNSS-1A satellite also failed.The Indian Regional Navigation Satellite System (IRNSS) is India's version of a navigation satellite, meant for both civilian and military use. There is no known explanation for the failure of the clocks on the Indian satellite as well, according to a report in The Hindu.Isro plans to launch more satellites to replace the damaged ones in the constellation later in 2017, according to a report in The Hindustan Times.Now there is no clear evidence that the failures of the atomic clocks of the IRNSS satellite flock by Isro is in any way related to failures of the atomic clocks in the Galileo constellation by ESA. An unidentified phenomenon could have taken down the clocks. The atomic clocks used by both Europe and India were supplied by Spectratime. Isro has imported the atomic clocks, and intends to question the supplier.Do you think you have an answer to this mystery? Let us know in the comments section below.