T.S. SUBRAMANIAN

On October 22, 2008, India joined a select band of five countries when its rocket called Polar Satellite Launch Vehicle (PSLV-C11) erupted into life in its launch pad at the spaceport at Sriharikota in Andhra Pradesh and put Chandrayaan-1 spacecraft into its initial orbit 18 minutes and 20 seconds later. The other countries/agencies to have sent spacecraft to the moon are Russia, the U.S., the European Space Agency, Japan and China. Thus Chandrayaan-1’s journey to the moon, which is about 3.84 lakh km away, has begun. It will be November 15 when the spacecraft ultimately reaches its destination at an altitude of 100 km around the moon.

In orbit

Chandrayaan-1 being put into orbit on its journey towards the moon opens a new chapter in the history of the Indian Space Research Organisation (ISRO). The latter’s truly indigenous space programme began on February 22, 1969, when ISRO launched a “pencil” rocket, weighing 10 kg from Thumba, near Thiruvananthapuram, Kerala. This “toy” rocket was a few feet tall. It rose a few km into the air. Today, the PSLV-C11 is 44.4 metres tall and weighs a massive 316 tonnes. Chandrayaan-1 itself weighed 1,380 kg on the ground. It will weigh 590 kg when it travels around the moon at an altitude of 100 km.

Chandrayaan-1 carries 11 scientific instruments. Of these, five instruments are from India and six from other countries. They will take pictures of the moon’s soil to gather information on its hills, valleys, craters, chemicals and minerals such as uranium, thorium, silicon, magnesium and so on. These instruments will also confirm whether there is water ice on the moon. An important instrument, built by India, is the Moon Impact Probe (MIP). This MIP, with the Indian flag painted on it, will eject from the mother-spacecraft, that is, Chandrayaan-1 and crash on the moon. That will be a truly historic moment when the Tricolour is dropped on the moon’s surface.