Moon sees first cotton-seed sprout

One of the cotton seeds carried to the moon by China's Chang'e-4 probe is the first ever to sprout on the moon, according to scientists of a mini biosphere experiment on Tuesday.

The first ever cotton sprout on the moon released by Chongqing University who led the design of this biological payload on the Chang'e-4 lunar mission. [Photo: CGTN/ Chongqing University]

After making the first-ever soft landing on the far side of the moon, China's Chang'e-4 mission pioneered the first mini biosphere experiment on the moon.

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.

The cylinder canister, made from special aluminum alloy materials, is 198 mm tall, with a diameter of 173 mm and a weight of 2.6 kg. It also holds water, soil, air, two small cameras, and a heat control system, said Xie.

More than 170 pictures have been taken by the cameras and sent back to Earth, according to the team.

Why were these species chosen?

Xie said potatoes could be a major source of food for future space travelers. The growth period of Arabidopsis, a small flowering plant related to cabbage and mustard, is short and easy to observe. Yeast could play a role in regulating carbon dioxide and oxygen in the mini biosphere, and the fruit fly would be the consumer of the photosynthesis process.

Researchers used biological technology to render the seeds and eggs dormant during the two months when the probe went through the final checks in the launch center and journey of more than 20 days through space.

After Chang'e-4 landed on the far side of the moon on Jan. 3, the ground control center instructed the probe to water the plants to start the growing process. A tube directs natural light on the surface of the moon into the canister to allow the plants to grow.