Moon and Venus

The crescent Moon and Venus, the “morning star,” will peek through the dawn twilight early tomorrow. They’re quite low in the east about a half-hour before sunrise.

In close-up photographs, Venus looks featureless. It’s completely blanketed by yellowish clouds, which hide the surface.

But ultraviolet images of the planet show some details in the clouds. In particular, they reveal dark streaks, which may extend deep into the atmosphere. The stripes absorb a huge amount of ultraviolet energy from the Sun.

So far, scientists aren’t sure just what makes up those stripes. The surrounding atmosphere consists of layers of clouds made of sulfuric acid and other compounds. The dark regions appear to contain sulfur compounds as well. But something else must be contributing to them.

Some have suggested the extra “something” could be microscopic organisms living in the clouds. The chemistry of some microbes on Earth matches some of the observations of Venus’s atmosphere.

Today, Venus’s surface is hellish — the atmosphere is extremely hot, dense, and toxic. Early in the planet’s history, though, it could have been much more comfortable, with oceans of liquid water. If life evolved on Venus, it could have been carried to the clouds by winds or other processes. Over time, it could have adapted to changing conditions.

So it’s possible that life could help fashion the dark stripes in Venus’s atmosphere.

Script by Damond Benningfield