BEIJING, Jan. 14 (Xinhua) – Night on the moon is dark and cold, yet Chinese scientists still do not know exactly how cold it really is. Chang & 4; and 4, which earlier this month made the first lunar landing in history on the hidden side of our natural satellite, will help them accurately determine the temperatures prevailing there.
A lunar day is equal to 14 on Earth and the nights have the same duration. Temperatures vary dramatically between day and night. According to scientific calculations, the highest temperature during the day can reach 127 degrees Celsius, while at night the minimum can reach less than 183 degrees.
In 2013, China launched the probe Chang & # 39; e-3, the country's first spacecraft to land on the lunar surface. After more than 60 moon nights have passed in the last five years, the scientific instruments of the device continue to function normally.
"It was a success, but Chang-e-3 was designed on the basis of temperature data provided overseas," says Zhang He, executive director of Chang-e-4 drilling project, which is part of China Academy of Space Technology (CAST).
"Without our own information on lunar temperature, we still do not know how cold a lunar night can be," he adds, adding, "Chang-e-4 will measure temperature differences between day and night, so help scientists to calculate the properties of the lunar soil. "
Tan Mei, CAST's consultant for the project, says that the Chang-e-4 will go into "sleep mode" during the lunar night due to the absence of solar energy and meanwhile will maintain a safe temperature depending on source of heat. of radioisotopes, a collaboration between Chinese and Russian scientists.
"We need to turn heat into energy to operate the thermometry and thus measure the temperatures at night," says Tan.
The descent vehicle is equipped with dozens of temperature data collectors, and information collected overnight will be transmitted after the wake-up probe on the lunar day, says Li Fei, a member of CAST and the team of vehicle designers .
Sun Zezhou, chief designer of Chang & # 39; e-4, and also a CAST member, says the probe will obtain firsthand data on moon night by directly measuring soil temperatures, its own surface and its interior equipment. .
Chang-e-4 isotope-based thermoelectric generation technology is being used for the first time in a Chinese spacecraft and is a prototype for future deep space exploration, Sun adds.
NASA's Curiosity explorer also has this technology, which allows it not to rely on sunlight, a factor that has hampered the operations of its predecessors, Opportunity and Spirit, complements.
"It is a technology that we must master if we are to reach the polar regions of the Moon or deep space beyond Jupiter, where solar energy can not be used as the main source of energy," warns Sun.