On March 5, 1982, a squat, armored Soviet lander settled onto a flat plain on Venus. Outside, the temperature was around 465 degrees Celsius, hot enough to melt lead. The air pressure was about 94 times that on Earth, like being nearly a kilometer under the sea.
The lander had very little time before the heat destroyed it. Its instruments ran on an automatic schedule, one after another. Then one of them, carefully designed and carried tens of millions of kilometers, measured the wrong thing.
Twins sent to Venus
Venera 14 was one of a pair. Its near-identical twin, Venera 13, launched on October 30, 1981, and Venera 14 followed five days later, on November 4. After a four-month journey, both landers plunged into Venus’s thick, toxic atmosphere.
Each lander was built like a pressure cooker in reverse, a sealed, heavily insulated sphere meant to protect its electronics from the crushing heat and pressure for as long as possible. Venera 14 came down about 950 kilometers southwest of its twin, on a basalt plain near a region called Phoebe Regio.
Racing against the heat
On Venus, every minute counts. The lander was designed to survive about 32 minutes on the surface. In the end, it kept working for 57 minutes before the heat won.
Because there was no way for controllers on Earth to react in time, almost everything happened automatically. The cameras switched on. A drill collected a soil sample for chemical analysis. And a spring-loaded arm swung down to press a probe into the ground.
The lens cap problem
That probe, called a penetrometer, was meant to measure how hard or soft the Venusian surface was. It would push into the ground and record how much the surface resisted, telling scientists whether it was like loose soil, packed dirt or solid rock.
But first, the cameras needed to see. During descent, their quartz windows were protected by covers. After landing, the covers popped off and fell to the ground, as planned.
One of them landed in exactly the wrong place. When the penetrometer arm came down, it struck the discarded lens cap rather than Venus. The instrument dutifully measured the compressibility of the lens cap instead of the soil. With no way to move the arm or try again, the measurement was lost.
Venus in color
Despite the mishap, Venera 14 was a major success. Along with Venera 13, it sent back some of the first color images ever taken from the surface of another planet. The pictures showed a strange, orange-tinted landscape of flat, cracked rock slabs and fine soil under a thick, glowing sky.
The orange color comes largely from Venus’s dense atmosphere, which filters sunlight and lets mostly reddish light reach the ground. The probe’s chemical analysis showed the surface rock was similar to basalts found on Earth’s ocean floors, pointing to a volcanic past.
Venera 14 also carried microphones to listen to the Venusian surface. Researchers later used the recordings to estimate the surface wind speed at just a fraction of a meter per second, barely a breeze.
The twin got it right
Fortunately, Venera 13 had better luck. Its penetrometer reached the ground and measured the soil, which turned out to be similar in firmness to compacted sand or soft rock.
Venera 13 also lasted much longer than planned, transmitting for 127 minutes before falling silent. Together, the two landers gave scientists a much better picture of Venus’s surface.
A lesson for planetary explorers
The lens cap incident has become one of the most famous bits of bad luck in space exploration. It’s a reminder of how unforgiving robotic missions can be. A spacecraft can travel millions of kilometers, survive a fiery atmospheric entry and land perfectly, only to have one small part fall in the wrong place.
Modern landers on Mars can wait for engineers on Earth to study images and choose where to place their instruments. On Venus, there’s no such luxury. Even today, no spacecraft has survived on its surface for more than about two hours.
More than four decades later, Venera 13 and 14 still hold a special place in history. They showed humanity the surface of our hellish neighbor in color, and one of them accidentally measured its own hat.