It’s been 12 days since Chang’E 3 embarked on its long journey to the moon. Its 380 thousand kilometer journey is about to end. Through this time, the rover’s rocket carried it only for 7 thousand kilometers and then fell off automatically, but it gave Chang’e 3 a speed of 10.8 kilometers per second rushing to the moon.
Then it slowed down at a distance of 100 kilometers above the moon and entered its orbit becoming its satellite. When it gets to the back of the moon, it will slow down again when it is at a distance of 15 kilometers above its surface where it will prepare for its landing.
Some engines will fire up and push against the direction it is travelling to slow it down so it can make a soft landing. It will take pictures surveying the surface, decide a good landing spot, stop its engines and let the low gravity of the moon bring it down.
Finally, it’s supporting legs will stretch out to contain the final impact. The whole landing process will take about 720 seconds, or 12 minutes.