China’s Chang’e 4 mission to the far side of the moon touched down a few weeks ago and has been investigating rarely-seen parts of the lunar surface since then. And now it has released a surprising finding — apparently the lunar nights are colder than expected.
It’s not just Americans who are chilly right now — the Chang’e 4 rover is feeling the cold on the Moon too. The rover has measured temperatures at night as low as minus 190 degrees Celsius (-310 degrees Fahrenheit) which the China National Space Administration (CNSA) described as “colder than scientists expected.” The measurements came from the Chang’e 4 after it spent two weeks in standby mode since landing. On Wednesday, it activated and began recording data and the temperatures recorded came from its first active lunar night.
The cold temperatures are not merely a curiosity — they could indicate that the geology is different on the far side of the Moon than the nearer side. The temperature difference between the expected and actual readings are “probably due to the difference in lunar soil composition between the two sides of the moon,” Zhang He, executive director of the Chang’e-4 mission, told the Xinhua news agency.
The far side of the Moon is the surface which perpetually faces away from Earth due to the Moon’s rotation. It is sometimes incorrectly called the “dark side” of the Moon because we cannot see it from Earth, though the hemisphere does receive light from the Sun. Communicating with this side of the Moon is difficult because there is no direct line of sight between there and Earth, making communications difficult. China solved this problem by sending an orbiting satellite called Queqiao to the Moon in advance of the rover launch. This satellite can collect information from Chang’e 4 and send it back to scientists on Earth.
Other news from the Chang’e 4 mission is that a probe called Yutu-2 (Jade Rabbit) was successfully deployed last week to perform experiments in the Von Karman Crater. The name Chang’e 4 comes from the name of a Chinese moon goddess, Chang’e or Chang-o, who had a pet rabbit who lived on the Moon. This Jade Rabbit has given its name to Yutu-2, the probe.
