India – The fifth and final orbit raising manoeuvre of Chandrayaan-1 spacecraft was successfully carried out today (November 4, 2008) morning at 04:56 am IST. During this manoeuvre, the spacecraft’s 440 Newton liquid engine was fired for about two and a half minutes. With this, Chandrayaan-1 entered the Lunar Transfer Trajectory with an apogee (farthest point to Earth) of about 380,000 km (three lakh eighty thousand km).

Though scientists rejoiced as the Chandrayaan blasted off, they knew they had a tougher job at hand, to put the satellite in moon’s orbit. That happened on Saturday evening and the mission was declared a success.

Indian scientists were worried because the last part of Chandrayaan’s journey was dangerous, as it had to go through an area in which the gravitational forces of the earth and moon nearly cancel each other out. Even a small deviation could have sent the spacecraft into a crash course towards the earth or on a path leading into deep space, but everything went according to plan.

When the spacecraft was about 500 km short of the moon, it was to be slowed down. The moon’s gravity would then pull the craft into its orbit. Later, it would be stabilised in a 100 km circular orbit.

PTI adds:

The successful lunar orbit insertion (LOI) was an important milestone for the Rs 386 crore moon mission whose success depended on today’s hit or miss manoeuvre.

According to space experts, the challenging LOI was not without danger because it meant traversing through an area in which the gravitational forces of the earth and moon nearly cancel each other out.

Consequently, even a small deviation could send the spacecraft into a frash course towards the moon or earth–or on a path leading into deep space.

Experts recall that about 30 per cent of unamnned moon missions of the US and former Soviet Union failed during LOI phase.


It (Chandrayaan-1 entering the lunar orbit) will go down in the history of Indian space in golden letters, ISRO Chairman G Madhavan Nair said.

India now has a “big leadership position” as far as space is concerned, he added.

November 17, 2008. Tags: , , , , , , , , , , , , , , , , , , . news. Leave a comment.