Our concepts of the cosmos can change in a hurry. A good example is Venus, which comes closer to us than any other planet. Over the past seven decades, our ideas about the planet have changed a lot. And they’re still evolving.

Venus is blanketed by clouds, which hide the surface. So as recently as the 1950s, some scientists thought the surface could be covered by oceans and by jungles teeming with life.

In the 1960s, though, the first spacecraft scanned Venus from up close. They found that its atmosphere is extremely hot, dense, and toxic – not a pleasant abode for life.

Later missions used radar to see through the clouds and map the surface. They found thousands of volcanic features. It looked like the planet had been repaved by molten rock hundreds of millions of years ago, then fell silent. But more recent studies appear to tell us that Venus could be as volcanically active as Earth.

There are even suggestions that microscopic life could live high in the sky, inside clouds made of sulfuric acid. But those ideas are still being debated. So our concepts of Venus could change even more in the decades ahead.

Venus is climbing into better view as the “evening star.” It’s quite low in the southwest as night falls. Tonight, it’s to the right or lower right of the Moon. Antares, the brightest star of Scorpius, is a bit closer to the upper left of the Moon. More about the Moon and Antares tomorrow.

Script by Damond Benningfield