On August 23, 1976, a small probe streaked through Earth’s atmosphere, crash-landing in a remote region of Siberia, 124 miles southeast of Surgut. On board was precious cargo—soil from our planet’s only natural satellite. It had been scooped up by a robotic lander and launched homeward three days earlier. Now, with its priceless payload successfully delivered, Luna 24’s mission was over. It would prove to be the Soviet Union’s final trip to the moon.
Beginning in January 1959 with the launch of Luna 1, the Luna program scored a number of historical firsts, but it also came with its fair share of failure. Soviet secrecy covered up 21 failed robotic launches directed at the moon—meaning Luna 24 was really Luna 45. And that doesn’t include the dozens of other missions during the 1960s that tested hardware to put a cosmonaut on the moon—an aspiration that never came to pass.
Nearly 50 years since that last lunar mission, Russian scientists hope to revive the historic work of their Soviet predecessors. The 21st-century incarnation of the Luna lander bears an uncanny resemblance to its Luna forebears with its clustered tanks and cylinders—a signature look of all spacecraft designed by the legendary NPO Lavochkin design bureau. But with modern electronics, the new Luna lander will be dramatically scaled down, and it also comes with a brand-new instrument module with vertically positioned solar panels.
Its mission will be different, too. While previous Luna missions primarily explored middle-latitude regions of the moon, Luna 25 is going to its south pole, a geological area that interests NASA and Jeff Bezos alike. If Luna 25 discovers these ancient deposits of ice, scientists will write a new chapter in the geological history of the moon—a fitting legacy for one of humanity’s greatest space programs.
The First in Space
The Soviet Luna program hid four generations of progressively larger and sophisticated probes, whose achievements read like the chronology of the Space Age itself.
The very first series of probes, developed in the late 1950s under the codename E1, were built to test the capability of the Soviet R-7 ballistic missile. These probes were topped with an extra booster to escape Earth’s gravitational field and push payloads toward the moon. After three failed attempts in 1958, the fourth probe, retrospectively named Luna 1, passed near the moon in October 1959 but missed its target (becoming the sun’s first artificial satellite). After another launch failure, Luna 2 finally reached the moon in September 1959. Clouds of sodium intentionally released from the inert rocket stages that carried the probes confirmed the success.
Following these first rudimentary probes, a far more sophisticated one, called Luna 3, succeeded in taking the very first photo of the far side of the moon. The ingenious machine developed the photo on board and beamed it to mission control—an incredible feat of engineering at the time. U.S. intelligence was so fascinated with Luna 3 that it organized an elaborate “kidnapping” of its copy for an overnight examination before returning it without incident.
The Soviet space program, having crashed probes into the moon and snapped photos of its surface, moved on to a much more difficult mission—designing a probe that could land on the moon and survive the experience. From early 1963 to the end of 1965, the USSR fired 11 rockets carrying small, flower-shaped E6 landers equipped with inflatable air bags to soften the landing. They all failed.
So the development of planetary spacecraft was transferred to Semen Lavochkin, who was famous for his World War II fighter planes. Like some other Soviet aircraft designers, Lavochkin shifted to rocket science after the war. Lavochkin died from a heart attack in 1960 and never saw the stunning success of the bureau that carried his name.
And those successes happened immediately. Lavochkin’s engineers succeeded on their first try at a “soft landing” with Luna 9, which touched down on the moon on February 3, 1966. The same team then modified its off-the-shelf probe to create the first ever lunar orbiter, which beamed back the melody of “The Internationale,” the anthem of the USSR. The E6 landers also confirmed that the lunar surface was indeed solid and not blanketed in a deep layer of dust capable of swallowing entire spaceships (as Arthur C. Clarke colorfully described).
In other words, it was possible to land humans on the moon.
The Race to the Moon
The Soviets’ lunar expedition scenario called for prepositioning of a backup return vehicle on the moon ahead of the arrival of a lone pilot—the maximum human payload the Soviet moon rocket could deliver at the time. In this scenario, a cosmonaut needed to cross the treacherous lunar terrain from a stricken landing ship to a spare escape rocket. That’s where the Lunokhod rover came in.
Not surprisingly, Lavochkin developed the rover, its landing platform, and the rollout ramp. But the project required expertise far beyond what the space industry could provide. So Soviet engineers who worked on military tanks contributed to the design of the chassis, while nuclear specialists provided a heater fueled by highly radioactive polonium.
The Soviet space program now had its rover and eager cosmonauts, but it was missing one vital piece of equipment—a reliable rocket to get them there. In 1969, two test launches of the giant N1 rocket ended with disastrous crashes, seriously derailing the Soviet Union’s dream of putting bootprints on the moon. In a last-ditch attempt to steal the limelight from NASA’s Apollo program, Lavochkin engineers configured the Lunokhod for remote control operations.
Lavochkin also hastily designed a small return rocket compatible with Lunokhod’s lander and ordered an ingenious drilling mechanism capable of extracting lunar soil and loading it into a sealed capsule at the top of the return rocket. This latter invention, known in Russian as lunocherpalka (lunar scooper), was intended to bring back lunar rocks automatically, proving the Soviet idea that exploration of the moon could be done faster, safer, and cheaper with robots.
Despite working in three shifts and on weekends at Soviet rocket factories and design bureaus throughout 1969, a familiar problem reared its ugly head: The Proton rocket, responsible for launching Lavochkin’s probes, was far from reliable. After several delays and a launch failure on June 14, Soviet engineers finally managed to put the Luna 15 scooper on a path to the moon on July 13, 1969, just three days before Apollo 11 blasted off from Kennedy Space Center.
If Luna 15 could pull off the soft landing and drilling, it still had a chance of bringing lunar samples back ahead of Apollo 11. But the probe suddenly cut communications with ground control during its descent. Its exact fate remains unknown, but it likely crashed into the moon’s surface.
Nearing the End
A total of five Soviet attempts to return samples failed between 1969 and early 1970. The very first Soviet Lunokhod rover was also destroyed in a launch mishap in February 1969, triggering a frantic operation to recover its radioactive heat source. (Thankfully, it survived the fiery crash without being breached.)
Finally, Luna 16 succeeded in bringing “moon rocks” back to Earth in September 1970. The 1,666-pound rover completed a record-breaking 6.5-mile trek across the moonscape in 10 months of operation. Despite moving no faster than 1.25 miles per hour, the eight-wheeled robot exceeded the time and distance covered by the Apollo expeditions.
While a cosmonaut never made it to the moon, Soviet engineers succeeded with seven soft landings of robotic probes, drove two robotic rovers on its surface, and got their hands on three capsules with precious lunar samples—a dress rehearsal for what NASA would attempt on Mars years later. But the spectacular exploits of Apollo astronauts on the moon largely overshadowed these amazing advancements in robotic space exploration.
The crushing blow for the Soviet lunar program wasn’t that Apollo 11 crossed the finish line first; it was that the U.S. lost interest after achieving its primary mission of beating the Soviets. After NASA’s last astronauts left the lunar surface on December 14, 1972, as part of the Apollo 17, the Soviet Union’s robotic lunar exploration program continued for years afterward, culminating with the final Luna 24 mission in August 1976.
Some nearly completed hardware from the E8 series were stuck on the ground, and even more designs were left on the drawing board. One completed copy of the Lunokhod ended up in the demo room at Lavochkin. Despite some interesting proposals for new generation E8 probes, Lavochkin was primarily consumed with the monumental, top-secret, and ultimately fruitless effort to return soil samples from Mars—something that nobody has been able to accomplish to this day.
With the collapse of the USSR in 1991, Russia’s ambitions for the moon mostly disappeared for three decades.
Luna 25: A Celestial Sequel
Russian planetary scientists spent much of the post-Soviet decades looking for commercial applications for their expertise and piggybacking their instruments and experiments on American and European spacecraft—but the world wasn’t standing still. Emerging space powers, including Europe, Japan, China, India, Israel and South Korea—along with the new crop of private companies like SpaceX and Blue Origin—set their sights on the moon.
While there were initial attempts to jump-start several lunar projects that lingered on the drawing board, the Roscosmos State Corporation had to start largely from scratch, as many Soviet-era veterans had retired or died. A new generation of engineers at NPO Lavochkin emerged, taking advantage of much lighter electronics and other new systems to develop a smaller, lighter lunar lander.
Responding to the latest discoveries of potential ice deposits in the lunar polar regions, Russian scientists now aimed their lander to the moon’s south pole, which still remains largely unexplored.
Luna 25’s multiple cameras will image the lunar surface from orbit during the descent and beam back stereo panoramas of the landing site. A miniature robotic arm will transport soil samples to the analytical sensors and test the mechanical properties of the surface. And most importantly, the 66-pound suite of scientific instruments will perform chemical and spectral analysis of the surrounding regolith with the primary goal of finding lunar water.
But Luna 25 also has more terrestrial aims. The Kremlin hopes the mission can boost Russia’s standing as a major space power, a reputation that has undergone decades of erosion. The official Russian strategy is for Luna 25 to be the first in a whole new crop of orbiters and landers that will carry 21st-century versions of the Soviet Lunokhods and sample-return rockets. There is also a plan to preserve lunar soil during drilling in its original cryogenic state so that potential water and other easily evaporating chemicals can be retained during the return trip.
Now, the big question: When will it launch? Roscosmos says as soon as October 2021, but if history is any indicator, that date is unlikely. Don’t expect Luna 25 to launch skyward until 2022—or beyond. Only time will tell if the name “Luna” will once again inspire the world to explore the cosmos.