Touchdown 鈥 mysteries of the moon鈥檚 far side to be revealed
Print Edition
THE desolate landscape on the far side of the moon — never visible from Earth — has waited billions of years for the first soft landing of a visitor from Earth.
At 10:15am yesterday, a variable thrust engine on China’s Chang’e-4 lunar probe was ignited with the assistance of the relay satellite Queqiao.
Chang’e-4’s relative velocity to the moon was lowered from 1.7 kilometers per second to close to zero, and the probe was adjusted to face the moon and descend vertically toward the Von Karman Crater in the South Pole-Aitken Basin.
At 100 meters up, the probe hovered to identify smaller obstacles and measured the slopes on the surface. Its computer calculated and selected the safest site.
At 2 meters above the surface, the engine stopped, and then the golden lander with a silver rover on top touched down on the desolate gray surface with four legs, throwing up some dust.
Important milestone for China
The probe performed the entire landing process, lasting about 12 minutes with no intervention from ground control.
The relay satellite then transmitted the first close-up photos of the moon’s far side back to a control center in Beijing.
The China National Space Administration later announced that the probe landed at the preselected landing area at 177.6 degrees east longitude and 45.5 degrees south latitude on the far side of the moon.
“It’s an important milestone for China’s space exploration,” said Wu Weiren, chief designer of China’s lunar exploration program.
Jia Yang, deputy chief designer of the Chang’e-4 probe, from the China Academy of Space Technology (CAST), added: “It is a perfect display of human intelligence.”
Named after Chinese moon goddess Chang’e, China’s lunar exploration program, which began in 2004, includes orbiting and landing on the moon, and bringing samples back to Earth.
“Landing on the far side of the moon is more risky than landing on the near side, the rugged terrain on the far side has raised many problems,” said Sun Zezhou, chief designer of Chang’e-4 probe, from CAST.
“But solving those problems might help lay the foundation for future space exploration.
“High-precision landing is a necessity for further exploring the moon and asteroids. We hope to be able to reach the whole moon and even the whole solar system.”
Zou Yongliao, director of the lunar and deep space exploration division of the Chinese Academy of Sciences, added: “The far side of the moon has unique features never before explored on site.
“The exploration of this virgin land by Chang’e-4 might bring breakthroughs.”
Lunar orbiters have shown the moon’s two sides are very different — the near side is relatively flat, while the far side is thickly dotted with impact craters of different sizes.
Scientists believe that the lunar crust on the far side is much thicker than the near side. However, the reason is still a mystery. Only on-site exploration might reveal the secrets.
The moon and Earth shared a similar “childhood.” But traces of the remote past on Earth have been erased by geological activities.
“The moon might provide some insights to the early history of Earth,” said Lin Yangting, a researcher at the Institute of Geology and Geophysics.
Stage set for return of astronauts
Exploring the Von Karman Crater in the SPA Basin is meaningful in another sense. The crater was named after a Hungarian-American mathematician, aerospace engineer and physicist, who was also the teacher of Qian Xuesen and Guo Yonghuai, the founders of China’s space industry.
Nearly 50 years have passed since people first stood on the moon. Can we return? How will radiation on the moon affect astronauts? How much water is there?
Scientists from China, Germany and Sweden hope to find the answers through Chang’e-4, and make preparations for people to return to the moon.
Robert Wimmer-Schweingruber, professor of the Institute of Experimental and Applied Physics of Kiel University in Germany, said that preparing for future human exploration of the moon was an excellent idea.
“If astronauts come back to Earth, the radiation on the moon is the only danger that remains in their body, so we need to understand that,” he said.
Johan Koehler, head of Solar System Science and Space Situational Awareness, Swedish National Space Agency, said exploration of the far side of the moon was a great achievement by China.
“We are very happy to be a part of it,” he said. “There is a theory that water on the surface of the moon is formed by the interaction of solar wind with the surface regolith. So this is something that Swedish scientists together with Chinese scientists want to answer.”
The Chang’e-4 mission, including the probe, the relay satellite Queqiao and a micro satellite orbiting the moon, is equipped with four payloads developed through international cooperation, providing more opportunities for the world’s scientists and combining human expertise in space exploration.
“I think one of the beauties of space science is that we do cooperate internationally,” Wimmer-Schweingruber said. “Space science to me is something important, also as a message of peace worldwide.”
For astronomers, the far side of the moon is a place of ideal tranquility, as the body of the moon shields against radio interference from Earth.
From there, they can study the origins and evolution of stars and galaxies, peering into the dawn of the universe.
The probe also took six live species — cotton, rapeseed, potato, arabidopsis, fruit fly and yeast — to the lifeless environment to form a mini biosphere, which is expected to produce the first flower on the moon.
Wu said: “Exploring the unknown is human nature. The moon is a mysterious world to us. We have a responsibility to explore and to understand it. Exploration of the moon will also deepen our understanding of Earth and ourselves.”
- About Us
- |
- Terms of Use
- |
-
RSS - |
- Privacy Policy
- |
- Contact Us
- |
- Shanghai Call Center: 962288
- |
- Tip-off hotline: 52920043
- 娌狪CP璇侊細娌狪CP澶05050403鍙-1
- |
- 浜掕仈缃戞柊闂讳俊鎭湇鍔¤鍙瘉锛31120180004
- |
- 缃戠粶瑙嗗惉璁稿彲璇侊細0909346
- |
- 骞挎挱鐢佃鑺傜洰鍒朵綔璁稿彲璇侊細娌瓧绗354鍙
- |
- 澧炲肩數淇′笟鍔＄粡钀ヨ鍙瘉锛氭勃B2-20120012
Copyright 漏 1999- Shanghai Daily. All rights reserved.Preferably viewed with Internet Explorer 8 or newer browsers.
