[Explanation] At 12:41 on July 23, at the Wenchang Space Launch Site on the northeastern coast of Hainan Island, China successfully sent the "Tianwen-1" Mars Rover into the scheduled orbit with the Long March 5 Yaosi carrier rocket, and opened China’s Mars exploration trip. On July 24, Pang Zhihao, the chief science communication expert of national space exploration technology, said that the landing of the probe is difficult.
[Explanation] The "Tianwen No. 1" plan will achieve "circumnavigation" through a single launch, that is, orbiting Mars, soft landing Mars, and patrolling and detecting on Mars. Pang Zhihao expressed the hope that through this launch, the five scientific goals can be achieved.
[Concurrent] Pang Zhihao, Chief Science Communication Expert of National Space Exploration Technology
One is to probe and study the topography of Mars; the other is to detect the soil on its surface, the distribution of water ice, and the composition of the surface of Mars; there is also to detect its ionosphere, the ionosphere in the atmosphere and The characteristics of the climate and some of its special conditions; the detection of its physical field and its internal structure; and the environment including its particles and ions should also be detected.
[Explanation] Pang Zhihao pointed out that Mars exploration is not simple. Since the first launch of a probe to Mars in 1960, humans have explored Mars for 60 years. In 60 years, humans have conducted 44 Mars explorations, but only 24 successful and partially successful missions, with a complete success rate of about 39%.
[Concurrent] Pang Zhihao, Chief Science Communication Expert of National Space Exploration Technology
Landing is difficult. One is that Mars is too far from the earth, so many of its signals, one is that the communication itself is difficult, and the signal delay time is very long, usually 10 minutes to 20 minutes one-way delay, so remote control cannot be carried out, and it must be done independently. , It has to complete a series of actions, one is aerodynamic deceleration, the second is parachute deceleration, the third is braking deceleration, and the fourth is landing gear landing. After it is finished, it will go from 4.8 kilometers per second to 0. There are a series of links in the middle, and no one link can go wrong. Sometimes the machine is shut down in foreign countries, and the hard landing breaks a second early. It must be allowed to soft land, which is almost impossible.
[Explanation] Pang Zhihao said that by studying Mars, we can understand the origin and evolution of the earth, and even predict the future of the earth.
[Concurrent] Pang Zhihao, Chief Science Communication Expert of National Space Exploration Technology
First of all, the day of Mars is about the same as that of the earth, 24 hours and 37 minutes. Second, the inclination of the Mars axis is about the same as that of the earth. There are four seasons in a year. Of course, this year, the time of this year is longer, 680 days. It is equivalent to two Earth years, because it runs in the outer circle, anyway, etc., and there are a lot of signs that Mars was the same as the Earth before.
[Explanation] It is understood that the "Tianwen-1" probe is expected to enter Mars orbit in 7 months, and thereafter it will continue to go through four stages including Mars capture, Mars mooring, off-orbit landing, and scientific exploration. .
Wen Mengxin and Shan Bingjie report from Beijing
Editor in charge: 【Luo Pan】