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China has landed a spacecraft on the side of the moon that's never seen from Earth. And NPR's Nell Greenfieldboyce reports it's part of a methodical plan that China has laid out for space exploration.
NELL GREENFIELDBOYCE, BYLINE: The moon is a bright, familiar face in the sky. The moon also has another side, but don't call it the dark side.
DAVID KRING: That's a Pink Floyd thing. It has nothing to do with geologic reality.
GREENFIELDBOYCE: David Kring is a lunar geologist with the USRA Lunar and Planetary Institute in Houston. He says the moon's far side is sometimes dark and sometimes lit by the sun, just like its near side.
KRING: The only thing that distinguishes the far side is it is the part of the moon that we cannot see from the surface of the earth.
GREENFIELDBOYCE: That's why it was a total mystery until 1959, when a Soviet spacecraft flew by and snapped the first fuzzy image. Flybys have pretty much been it. Until now, no probe ventured to its surface.
KRING: We have had 27 successful missions to the surface of the lunar near side and zero to lunar far side. So it really represents unexplored territory.
GREENFIELDBOYCE: State-owned Chinese television reported that the Chang'e-4 spacecraft touched down at 10:26 a.m. Beijing time. The China Global Television Network broadcast remarks by Wu Weirin, the chief designer of the lunar exploration project.
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WU WEIRIN: (Through interpreter) It is of human nature to explore unknown places in the world. That's why we chose to go to the far side of the moon among all the choices we had, even if it means we will face more challenges.
GREENFIELDBOYCE: Being on the other side of the moon is challenging for communications, so China had to add a satellite to relay messages back to Earth. The lander also has a rover to explore what scientists say is a more primitive, ancient surface than the near side because it hasn't been flooded by lava eruptions.
Joan Johnson-Freese is a space policy analyst at the Naval War College. She says China is closely following plans that it previously set out for space. It's pursuing this robotic moon program as well as a human exploration program that's building a large space station.
JOAN JOHNSON-FREESE: And it's highly probable that within the next three to five years, when both of these programs are completed, that they will combine the technologies and announce a human program to the moon.
GREENFIELDBOYCE: President Trump has directed NASA to work towards returning astronauts to the moon. No one has been there since 1972. Nell Greenfieldboyce, NPR News.
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