The crew on board the China Space Station are preparing for their second spacewalk since they arrived in October. They're expected to carry out the operation on Sunday. The three-member crew that includes China's first female astronaut Wang Yaping who is in space for a second time. They carried out their first spacewalk last month. And two weeks ago, they gave a science lesson from the space station to Chinese students. The Shenzhou-13 crew conducted their first space walk last month. Let's take a look back at the mission.