Bangalore to Mars

The container truck bearing the Mars orbiter being received at SHAR, Sriharikota.

THE truck trailer that rolled ever so gently from Bangalore to Sriharikota at a speed of 10 kilometres an hour and covered a distance of 345 kilometres would have fooled any passer-by into thinking that some inconsequential cargo truck was on its way to some port.

The 1,350-kg Mars orbiter carrying five scientific instruments held in a sophisticated container with special contraptions hit the road on the first lap of its journey to Mars on October 2 and reached the spaceport more than 34 hours later. The five payloads, all built by the Indian Space Research Organisation’s (ISRO) Space Application Centre in Ahmedabad, the Laboratory for Electro-Optic Systems (LEOS) in Bangalore and the Space Physics Laboratory in Thiruvananthapuram, were integrated into the spacecraft bus at the ISRO Satellite Centre, Bangalore.

Deviprasad Karnik, ISRO spokesman, said the spacecraft underwent a battery of tests at a facility at the ISRO Satellite Centre where vacuum conditions in space and the solar radiation that would fall on it were simulated to check the orbiter’s space-worthiness and its performance level under such conditions. The orbiter faced thermal-balancing tests to verify whether the heat falling on the various places in the spacecraft during its 300-day odyssey in space would be within permissible limits. Tests were also done to see whether the orbiter’s “appendages” (its solar panels and high-gain antenna) deployed as predicted. The spacecraft was then ferried to the ISRO Satellite Integration and Test Establishment (ISITE), also in Bangalore, where it was subjected to vibration and acoustic tests.

“After qualifying the spacecraft for its space-worthiness, it was put into a special container, which had a controlled environment and monitoring devices, and transported from Bangalore to Sriharikota,” said Karnik.

The container had a console to monitor the health of the spacecraft by constantly checking the temperature, humidity and vibration levels during transportation. The solar array drive assembly, a critical component of the orbiter, was purged by pumping pure, dry nitrogen gas into it. This took place within the container. The spacecraft was mounted on a platform, which was cushioned to enable it to withstand the effect of vibration during its road journey to Sriharikota. On reaching the spaceport, the orbiter underwent more pre-launch tests. It was filled with fuel on October 15 and married up with the fourth stage of the PSLV-XL on October 20.

T.S. Subramanian