After the Sun and Moon, Venus is the brightest object visible from Earth—a barren, desolate world that is both familiar and eerily alien.
From 1961 to 1984, as NASA prioritized its Apollo Moon missions, the Soviet space agency conducted the less-publicized Venera program, aiming to unravel the mysteries of Venus. Throughout this period, numerous probes and landers were launched to gather data and capture images of this enigmatic world.
Of these, 13 probes successfully penetrated the Venusian atmosphere, with ten managing to land on the planet's surface.
While the success rate might not have met Soviet aspirations, it denoted a remarkable accomplishment: these were the first human-made objects to enter another planet's atmosphere.
What most perplexed engineers and researchers was that after successfully landing, the probes would soon encounter abrupt, catastrophic failures. Their operational lifespan ranged from 23 to 120 minutes.
On December 15, 1970, Venera 7 entered the Venusian atmosphere. Unfortunately, its parachute malfunctioned, causing it to plummet for 30 minutes before crash landing on Venus at 38 miles per hour.
Remarkably, it survived long enough to transmit data, revealing a surface temperature of around 900 degrees Fahrenheit and a pressure analogous to being more than half a mile underwater on Earth. Venera 7 became the first spacecraft to soft land on another planet and the first to transmit data from there back to Earth.
Venera 9 would be the first device to return images from another planet. It became one of just four to ever do so successfully due to the conditions of the planet's atmosphere quickly rendering the probes useless.
The rare images reveal a bleak world of cracked rocks, arid plains, and hostile desert. Later probes produced sepia-tinged wide-angle panoramas of the surface.
More advanced probes were then sent, which measured wind speed using microphones and attempted to map the surface using radar, but all ultimately succumbed to the harsh environment.
The data from the Soviet landings offer vivid insights into Venus. The planet's sulfur content would create a repulsive rotten egg odor, its rain—acidic enough to dissolve human flesh—and the consensus is that the harshness of the environment precludes the existence of familiar life forms.
Yet, in 2012, Russian scientist Leonid Ksanfomaliti published a paper suggesting that images from the 1982 Venera 13 probe hinted at potential life forms. He believed that certain objects, which appeared mobile, resembled a "disk," a "black flap," and even a "scorpion." These, he proposed, might be creatures that evolved to thrive in Venus's extremes.
Ksanfomaliti's claims, while stirring conspiracy theories about classified photos and potential signs of extraterrestrial life and structures, were met with substantial skepticism from the broader scientific community.
While we can be reasonably certain that the terrific heat and crushing pressure on the surface of Venus is responsible for the short lifespans of the probes to have landed on it, it remains surprising that so few should have managed to transmit a single image back to Earth.
There remains a great deal to be learned about Venus.