FOURTH STAGE OF PSLV-C19 BURNS UP OVER CENTRAL ATLANTIC

Close on the heels of the Chinese experimental space station Tiangong - 1 burning up over southern Pacific soon after the entry into earth atmosphere on April 1, Sunday, the fourth stage (PS4) of ISRO’s Polar Satellite Launch Vehicle ( PSLVC19) weighing about 1 tonne reentered over the central Atlantic at 14.06 UTC on April 3.

Jonathan McDowell, an astrophysicist at the Harvard- Smithsonian Center for Astrophysics tweeted that ‘ The 1tonne PS4 rocket stage from#@ISRO’s 2012 PSLV C19 launch reentered over the central Atlantic at 1406 UTC Apr 3.

The Polar Satellite Launch Vehicle, in its 21st flight (PSLV-C19), launched India’s first Radar Imaging Satellite - RISAT-1 into a Polar Circular Orbit with an altitude of 480 km (+ 40.5 km) and orbital inclination of 97.552 (+ 0.2) on April 26, 2012. RISAT-1 weighing 1858 kg is the heaviest satellite being launched by PSLV then.

An ISRO scientist said it is a general phenomena that the Lower stages, which are closer to the earth enter the earth atmosphere no sooner their job is over.

Where as upper stages (3rd or 4th stage) of a launch vehicle will also go into the orbit after injecting the spacecraft.

But they lose their altitude and enter the earth atmosphere after a period of time and would burn up in the atmosphere.