Full coverage: China Tiangong-2 Space Lab Launch

We turn again to our studio guest, Professor Yang Yuguang, a researcher at the China Aerospace Science and Industry Corporation. Let's talk some more about this launch.

Q1: Authorities have said it will happen sometime between tomorrow and the 20th of this month. Tell us how they will choose the exact time for the launch. What factors are they weighing?

Q2 : We know China is aiming to build a permanent manned space station by 2022. There are now only six years left. How far away are we from this goal?

Q3: China is the third country after Russia and the United States to be able to launch astronauts into space. Could you please compare the current status of China's manned space program with the other two?

Q4: Astronauts will try to grow plants in Tiangong-2. Tell us the significance of this experiment.