For the first time, the Earth and the moon's mysterious "far side" have been photographed together in a beautiful group shot.
The scene was captured by Longjiang-2, a lunar micro-satellite developed by students at the Harbin Institute of Technology (HIT) in Heilongjiang Province in northeast China and launched as part of the China National Space Administration's (CSNA) latest lunar lander mission. As a testament to the extreme distance from which this shot was taken, it took the Dutch Dwingeloo Radio Telescope 20 minutes to download the relatively tiny 16-kilobyte file.
"This image represents the culmination of several observing sessions spread over the past few months where we used the Dwingeloo telescope in collaboration with the Chinese team from Harbin University of Technology, who build the radio transceiver on board Longjiang-2, and radio amateurs spread across the globe," the team wrote in a blog post.
A new chapter in lunar exploration
On Jan. 3, 2019, the China National Space Administration (CSNA) made history by becoming the first country to ever land a craft on the moon's far side, successfully touching down its Chang'e-4 probe and accompanying rover on the lunar surface.
This has naturally led to some spectacular photos, such as the one of the Yutu-2 rover below exploring its new home, beamed back to CSNA.
The Chang'e-4 probe landed in the Von Kármán crater, a lunar impact crater located within an even larger crater known as the South Pole–Aitken basin. This massive crater — the oldest scar on the lunar landscape — is one of the largest impact craters in the solar system, stretching some 1,600 miles in diameter and reaching a depth of more than 8 miles.
For some scale, NASA's Lunar Reconnaissance Orbiter recently approached the Von Kármán crater from the east and snapped a shot of the Chang'e-4 probe. At only 2 pixels wide in the below image, it's a stunning reminder of just how large the moon truly is.
While it's often nicknamed the "dark side" of the moon, the far side actually receives as much sunlight as the tidally locked near side that faces Earth. Because line of sight is impossible with Earth, the Chang'e-4 relies on a relay satellite called Queqiao — located some 40,000 miles from the lunar surface — to transmit data back to China's mission control.
The Longjiang-2 micro-satellite was originally unloaded by the Queqiao relay satellite with a twin unit called Longjiang-1. The latter micro-satellite unfortunately malfunctioned, leaving Longjiang-2 as a sole survivor in lunar orbit. Nonetheless, the little 100-pound unit — about the size of a large shoebox — has continued to operate flawlessly, testing out, as the Planetary Society reports, "future radio astronomy and interferometry techniques."
In addition to the student-developed camera which captured the historic shot, the micro-satellite also has a second imager built by Saudi Arabia.
As China expects its latest lunar mission to continue for at least "a few years," we can look forward to many more spectacular images from this side of the lunar coin in the days ahead.