Thirty-five years ago this month, a pair of balloons took a high-speed joyride through the clouds of Venus. They zipped along at 150 miles per hour, transmitting details on the Venusian atmosphere back to Earth. By the time their batteries died, they’d skirted a third of the way around our sister planet.

The balloons were part of twin Soviet missions, Vega 1 and 2. They actually had two destinations — Venus and Halley’s Comet. In fact, the name “Vega” comes from the Russian names for Venus and Halley.

As they sped past Venus in June of 1985, each one dropped off a lander and a balloon. Each lander survived on the surface for about an hour. They measured a surface temperature of 865 degrees, and pressure more than 90 times greater than at the surface of Earth. They also measured a sample of the surface, finding that it consisted of volcanic rock.

The balloons deployed about 35 miles high. That’s in the middle of Venus’s three layers of clouds. They measured temperature and pressure, the composition of the atmosphere, and more. Driven by strong winds at that level, each of them covered about 7,000 miles — providing what is still our only long and close look at Venus’s clouds.

And Venus just peeks into view in the dawn sky now. Tomorrow, it’s close to the crescent Moon as the sky brightens, quite low in the east-northeast. It’s the brilliant “morning star.” It’ll move higher into the sky, and into better view, over the coming weeks.

Script by Damond Benningfield

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