The 29-hour countdown for the launch of India's eighth navigation satellite IRNSS-1H began at 2 p.m. on Wednesday at the Sriharikota rocket port. (Photo: PTI)

Nellore: NASA’s Two Element System, which keeps tabs on all objects in space, might spot the IRNSS-1H satellite before it begins to drift back to earth.

Isro former director Dr M.Y.S. Prasad said NASA periodically updates data of active and passive satellites as well non-functional satellites apart from debris after due confirmation.

He said the Vikram Sarabhai Space Centre in Thiruvananthapuram had tracking facilities and it was not difficult to predict the reentry time and trajectory in advance to take necessary precautions.

He said that all satellites in low earth orbits fall back through the atmosphere at one time or the other and burn up during reentry. He said satellites with orbits with a perigee of more than 180 km perigee were safe.

“It is like any other space debris and it will burn up soon after entering the earth atmosphere because of temperatures running into thousands of degrees. We can identify the place where the debris would fall one week before such an eventuality” Dr K. Sivan, director, Vikram Sarabhai Space Centre, Thiruvanan-thapuram, told this newspaper.

Replying to a question on the threat posed by the propellant in the satellite, he said, “we have depleted all the propellant through the gap in the heat shield and the fourth stage.”

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