The Chang’e 3 mission is the latest step in China’s ambitious space program. It is set to carry out some tasks that so far haven’t been done by any other country in the world.
Our reporter Ai Yang sat down for an exclusive interview with Ouyang Ziyuan. The 78-year-old is the senior advisor of China’s lunar probe project, and is sometimes referred to as the father of Chang’e missions.
"It’s very difficult to soft land on the moon because there’s no atmosphere. A soft landing must ensure all equipment is safe on board the lander and the rover. The lander will start working immediately after landing, by observing space using an optical telescope. So this will be a combined exploration of the moon by the lander and the rover.
The lander has boosters, which allow it to remain hovering at about 100 meters above the lunar surface. Then using special cameras it will look for a flat place to land on. Then when it’s about four meters above ground, its engine will stop. The lander’s four legs are shockproof and will ensure a soft landing." Ouyang Ziyuan said.
"The Chang’e 3 mission will achieve three "firsts". Number one: space observation from the moon. This is the dream of many astronomers because atmosphere, wind, snow and pollution don’t obstruct visibility as they do on earth. The result is also better because of the longer periods of uninterrupted observation from the moon due to it orbiting the earth. One day of observation on the moon is equivalent to 14 days on earth.
Number two: we have an ultraviolet camera on the lander to monitor the earth. This camera is different from the one used by America’s Apollo 16. Ours can see the formation of the earth’s plasmasphere and its density change. It’s better than a satellite, which can only record data section by section as it orbits around the earth. On the moon it can observe half of earth at a time without moving. This is something people have always wanted to do.
Number three: we will be the first to learn the structure and layers of the moon 100 meters below its surface with radars installed at the bottom of the rover. As the rover drives on the lunar surface, it will be as it can cut and see what’s 100 meters below. These three highlights are what no other countries have done so far." Ouyang Ziyuan said.
"The human knowledge of the moon is largely derived from samples brought back to earth by Apollo 16. In 1978, US president Jimmy Carter gifted us one gram of their samples and we did lots of research using just half of that gram. Our Chang’e 5 will also return with samples. I believe within 2 to 3 years we will be able to carry out very systematic and accurate research with the samples.
For now, one tough test the Chang’e 3 mission must pass is withstanding extreme cold conditions. The rover’s wings collect solar energy during the day, which allow it to function. But at night none of the equipment works, because the temperature drops as low as minus 180 degree celcius. Electronic devices are damaged if they’re colder than minus 40 degrees, so we will use atomic energy storage batteries to heat them up at night and keep them operational. The batteries have to be able to work for long periods at a time, as one night on the moon lasts two full weeks on earth." Ouyang Ziyuan said.
