Chinese space, Space Science, The Moon

Chang’e-4 in sleep mode, Videos of rover and the landing, + Cotton shoots sprout

[ Update Jan.16.2019: There has been some confusion about the photos of the cotton plant shoots. A couple of early images circulating in the Chinese press were actually from a ground unit. However, the one shown below is apparently from the lander:

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China’s Chang’e-4 mission on the far side of the Moon has begun initial operations with the scientific instruments on board the lander and has taken a short drive of the rover Yutu-2 (Jade Rabbit-2):

An earlier video showing the deployment of the rover:

A press conference was held this week with managers of the Chinese space program, including “Sun Zezhou, chief designer of the Chang’e-4 probe”. They discussed the challenges of operating the systems in the lunar environment: China’s new lunar rover faces challenges on moon’s far side – Xinhua | English.news.cn

Both the lander and the rover entered a “sleep mode” on Sunday as the first lunar night after the probe’s landing fell, according to Wu.

One night on the moon lasts about 14 days on the earth, during which the temperature falls as low as minus 180 degrees centigrade. There is no sunlight to provide power to the probe, which will survive the night with its thermal control system with a radioisotope heat source.

The landing went quite smoothly:

Sun told reporters that the Chang’e-4 probe had achieved the expected landing precision. The telemetry information and images taken by the probe showed that the spacecraft effectively avoided obstacles during its descent.

“It hovered at around 100 meters above the lunar surface and moved about 8 meters towards the southwestern direction. After its landing, we discovered large craters with a diameter of more than 10 meters on both the southern and northern sides of the probe, and it successfully avoided them,” Sun said.

Scott Manley analyzes the landing video:

I took the best video from an official source, then corrected it for real time, interpolated frames to smooth it using butterflow. Then using the high quality video I try to map through all the features we see to provide an idea of how large the craters are.

The scientific experiments on board the lander include a mini-biosphere to demonstrate growing plants on the Moon. A cotton-seed quickly sprouted: China Focus: Moon sees first cotton-seed sprout – Xinhua | English.news.cn

Professor Xie Gengxin, of Chongqing University and chief designer of the experiment, said a canister installed on the lander of the Chang’e-4 probe contained the seeds of cotton, rapeseed, potato and Arabidopsis, as well as eggs of the fruit fly and some yeast, to form a simple mini biosphere.

Images sent by the probe showed that a cotton sprout had started to grow, though no other plants were found growing.

A photo of the shoots: China’s plants sprout on moon’s far side – Chinadaily.com.cn

“At 8 pm on Jan 12, Chang’e 4 sends back the last photo of the bio test load showing that tender shoots have come out and the plants are growing well inside the sealed test can. It is the first time humans conducted a biological growth and cultivation experiment on the surface of the moon.” – Chongqing University and ChinaDaily.

The plant experiment, however, was a brief one. The seeds will not survive the night-time temperatures.

This sort of research from Chang’e-4 will provide data in support of Chinese human missions later:

A sample return mission – Chang’e-5 – is the next Moon mission on the agenda: China’s lunar exploration program to meet goal of sample returning by 2020: official – CCTVPLUS

The Chang’e-5 probe will be launched by the end of this year and will collect two kg of samples and bring them back to Earth. China plans to launch a probe in 2020 that will orbit, land and rove on Mars the following year, according to Wu.

More reports on Chang’e-5:

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