Eagle Station

The long shadow cast by the Chang’e-10 lunar lander stretched across a gray moonscape of compacted, fine-grained dust, rocks, and pebbles. There were no other shadows. This was the highest point on the lunar surface, rising nearly two thousand meters higher than Earth’s Mount Everest. Of course, since the approach slopes were so much more gradual, the vistas were not as dramatic.

Bulky in his space suit, Colonel Tian Fan leaned over the wheeled lunar rover he had just successfully extracted from a storage bay in the lander’s lower descent stage. He pulled open a small control box located on the rover’s side and flipped a switch.

Inside the rover’s chassis, a small rod of radioactive plutonium-238 slid out of its protective graphite container and into a radioisotope thermoelectric generator, or RTG. Now active, the RTG converted the heat produced by radioactive decay into electricity. An indicator light glowed green, showing that power was being produced. Unlike batteries or solar panels, the RTG would produce electricity continuously — even during the coming two-week-long lunar night, when temperatures would plunge three hundred degrees Celsius.

Tian waited a few more seconds for the system to stabilize and then flipped a second switch. This one activated the rover’s computer. More lights glowed. Satisfied, he closed the control box and stepped back.

Moments later, the rover started up and moved off slowly across the lunar surface. Guided by its programming, it drove a couple of hundred meters away from Chang’e-10 and parked. Although it was approximately the same size as the rovers carried by America’s long-ago Apollo missions, this machine had a very different purpose.

Equipped with a raised blade at the front and a hopper in place of seats, the rover was designed to scrape up regolith — loose dirt, dust, and rocks — and then feed it into an automated furnace and chemical reaction unit built into the base of the lander. Over the next several weeks, remotely controlled by technicians back on Earth, the system would accumulate stores of hydrogen, oxygen, and water separated out of the regolith. Those vital life-support and fuel supplies would significantly reduce the amount of payload mass needed by future manned missions to this site.

Tian turned and moved off toward where Kirill Lavrentyev was working, gliding and hopping across the loose gray surface at a rapid clip. Their EVA suits, though still awkward to move in, were more flexible than those worn by America’s Apollo astronauts. “How’s it going?” he asked.

“The last beacon is set and operating,” the Russian cosmonaut reported, looking up. He backed away from the small radio antenna and transmitter he’d just finished anchoring in place.

“Excellent work,” Tian said. Setting up a network of six radio beacons across a stretch of the crater rim had been one of their primary tasks for this landing. Signals from those beacons would help guide China’s Mă Luó automated cargo landers to precise touchdowns during planned follow-on missions. “Then it’s time for us to prep for takeoff.”

“Twenty-four hours seems a very short time to spend here after so many months of training,” Lavrentyev said somberly. “Especially after so many decades.”

Tian knew what he meant. Both men were aware of the bittersweet irony involved in this mission. It had been more than half a century since anyone had walked on the moon. And while he and the Russian cosmonaut were only the thirteenth and fourteenth men in all of human history to do so, their achievement must remain a closely guarded secret for the time being. He laid a gloved hand on the other man’s shoulder. “Remember, Kirill, we’ll be back. And soon.”

Lavrentyev nodded.

Together, they turned and headed back to the waiting Chang’e lander.

Two hours later, Chang’e-10’s ascent engine fired. The upper half of the lander, separating from its descent stage, soared into space. It climbed fast along a rising arc that would intercept the Federation 2 spacecraft as it swung back around the moon’s far side. From his command pilot’s station, Tian monitored their progress. He glanced across the tiny cabin at Lavrentyev. “I show a good burn. Our trajectory looks perfect.”

The Russian studied his own readouts and nodded. “I concur.”

Quickly, Tian entered a series of orders on his display. “Ascent engine command override is off. Engine Arm is off.” Now that they were off the surface and on course to rendezvous with Federation 2, they no longer needed their powerful rocket motor. From now on, Chang’e’s smaller reaction control system thrusters would handle any necessary last-minute maneuvers.

Beside him, Lavrentyev moved on to his next task. “Standing by to deploy our camouflage stage.” He entered a command on his own MFD. “Deploying now.”