Chang'e-4 is set to release a rover to map contours and surface features around the crater and look at the geology.
The crater is deep, and it is thought to possibly contain rocks that have never been seen before. Chinese scientists hope the probe might return with soil samples, bringing back clues about how the moon formed.
The moon's orbit around the earth matches its rotation around itself, a phenomenon called tidal locking. It means that on Earth, we always see the same side of the moon and perceive the other one as being dark.
However, both sides of the moon have two weeks of sunlight followed by two weeks of night. It's only when we perceive the moon as being full that the far side is fully shrouded in darkness.
Long unseen by humans
The term "dark" instead refers to a sense of mystery — with the far side of the moon unseen by human eyes until a spacecraft was sent around it.
The far side has long fascinated scientists but was only first observed and photographed in 1959 by the Soviet space probe Luna 3. The Apollo 8 astronauts were the first to see it with the naked eye. But no one has ever landed on it.
"If we are as a species going to study the moon further, we need to go to the far side," NASA Watch editor Keith Cowing told DW.
China aims to become a major space power by 2030, and it aims to start construction of its own manned space station later this year.
Chang'e-4 is the second Chinese probe to land on the moon, after the Yutu (Jade Rabbit) rover mission in 2013.
Fly me to the moon
On July 27, 2018 a rare dual celestial phenomenon occurred: a relatively long lunar eclipse or "blood moon" due to the moon's change in color while shadowed by earth, and the nearest approach of planet Mars in 15 years. The very rare cosmic coincidence had sky gazers out in force. Since the beginning of time, however, the moon has been revered for its magic, mystery and cultural significance.
Religious symbolism and astrology
People have worshipped the moon since the beginning of time, structuring their lives around its patterns and revering its perceived forces. Sometimes time was counted in moons rather than days or months. The bronze Nebra sky disc, found in Saxony-Anhalt in 1999, represents the duality of early astronomy and spirituality. The disc is estimated to be 3700-4100 years old.
The meaning of…
In the visual arts, the moon has been used to symbolize a variety of themes: innocence, the Virgin Mary, female sexuality. However, the overwhelming association has always been one of romance. Artists frequently looked to the moon for its magic, as displayed here in Caspar David Friedrich's "Two Men Contemplating the Moon" from 1820.
Immortal muse of the poets
The moon has played a pivotal role in literature since time immemorial. In poetry, it's often used to express melancholy and longing — or often solace, as in Johann Wolfgang von Goethe's poem "To the Moon." The opening verse of the poem reads: "Bush and vale thou fill'st again / With thy misty ray / And my spirit's heavy chain / Castest far away."
Howl at the moon
The moon may inspire owls and wolves to sing, but humans have also made a habit of howling at it. Famous examples include Matthias Claudius' beloved German lullaby "Gently the Moon has Risen," Elvis Presley's version of Rodgers and Hart's "Blue Moon" and Pink Floyd's seminal 1973 album "The Dark Side of the Moon."
Horror and romance
Mark Twain once said "Everyone is a moon, and has a dark side which he never shows to anybody." Since ancient times, legends have abounded about people who turn into wolves at the full moon. The werewolf has been a perennial cinema favorite — as in "The Wolf Man" of 1941, pictured. But the moon has played a role in every genre, including romantic comedies like the 1987 romcom "Moonstruck."
Blockbuster of the century
With the historic moon landing in 1969, the moon could well have lost its remaining secrets — and luster. Suddenly people were there, exploring its mysteries first-hand — and even taking photographs. Science, it seemed, had finally conquered the Earth's mysterious satellite.
But the magic of the moon wasn't destroyed by its human conquest. Indeed, it still continues to inspire, and in 2013 Chinese artist Ai Weiwei and his Danish collaborator Ólafur Elíasson launched their "Moon" project. At www.moonmoonmoonmoon.com people can immortalize their own drawings of the moon. "Leave your fingerprint and see the shared moon grow as others reach out too," implores the website.