BEIJING, Oct 19, 2021 (BSS/AFP) - The first lunar rocks brought back to 
Earth in decades show the Moon was volcanically active more recently than 
previously thought, Chinese scientists said Tuesday.

   A Chinese spacecraft carried lunar rocks and soil to Earth last year -- 
humanity's first mission in four decades to collect samples from the Moon, 
and a milestone for Beijing's growing space programme.

   The samples included basalt -- a form of cooled lava -- from 2.03 billion 
years ago, scientists found, pushing the last known date of volcanic activity 
on the moon closer to the present day by as much as 900 million years.

   Analysis of the samples "reveals that the Moon's interior was still 
evolving at around two billion years ago", the Chinese Academy of Sciences 
(CAS) said in a statement.

   Previous moon rocks brought back by US and Soviet missions showed evidence 
of lunar activity up to 2.8 billion years ago, but left a gap in scientists' 
knowledge about the more recent history of Earth's natural satellite as they 
were from older parts of the lunar surface.

   The Chang'e-5 mission -- named after a mythical moon goddess -- collected 
two kilogrammes (4.5 pounds) of samples from a previously unexplored area of 
the moon called Mons Ruemker in the Oceanus Procellarum or "Ocean of Storms".

   The area was selected as it was thought by scientists to be more recently 
formed, based on the lower density of craters from meteors on its surface.

   "Altogether those results are extremely exciting, providing amazing 
science and results on understanding the lunar formation and evolution over 
time," Audrey Bouvier, a planetology professor at Germany's University of 
Bayreuth, said in a video message at a Beijing press conference on Tuesday.

   The latest findings -- published in three papers in the Nature journal on 
Tuesday -- open up new questions for scientists trying to decipher the 
history of the Moon.

   "How did the Moon sustain volcanic activity for so long? The Moon is 
naturally small and should disperse heat quickly, or so the thinking goes," 
CAS researcher Li Xianhua, one of the authors of the studies, told reporters.

   The Chang'e 5 samples marked a major step for the Chinese space programme, 
which has sent a rover to Mars and landed another craft on the far side of 
the Moon.

   The country, racing to catch up with the United States and Russia, sent 
three astronauts to its new space station on Saturday, which is expected to 
become operational by 2022.