Full coverage: China Tiangong-2 Space Lab Launch

Now let's go back to our guests -- Professor Yang Yuguang AND Director General Nasir Mahmood.

Q1: Several countries, such as China, Russia, and the U-S, have very active space programs. What is the significance of this?

Q2: What challenges are they facing?

Q3: At which stage is our space program now, in terms of development?

Q4: China is going to send a rover to the surface of Mars by the end of 2020. Other countries also want to explore the Red Planet. For instance, NASA will launch another Mars rover in 2020. The United Arab Emirates will also send an orbiter to Mars in the same year. What are the prospects for Mars exploration?