Life On Venus?

A handful of scientists are excited about the prospect of life in the upper atmosphere of Venus. Why? The detection of phosphine (below, left), a gas that, to the best of our knowledge, does not occur unless life as we know it exists.

Challenges remain. The “best of our knowledge” is still in the kindergarten stage when it comes to unlocking the deep secrets of the universe. The universe has confounded scientists and their expectations for centuries.

• Meteor showers were thought to be the anger of the gods. Now we know they are the dust trails orbiting behind comets.
• Galileo’s intellectual peers were astonished when he discovered Jupiter had moons, Venus had phases like our moon, and that moon had mountains and valleys like Earth.
• Mars was first thought to have seasonal changes of plant life and canals. Then in the 60s, the first probes found it cratered like the moon. Now we know it has subsurface permafrost, shield volcanoes higher than any in the solar system, and a valley that dwarfs the Grand Canyon of Arizona.
• The moons of Jupiter and Saturn were thought to be cratered and dead like our moon appears, but now we know they have plate tectonics, volcanoes, geysers, and even subsurface oceans that dwarf the Earth’s component of water.
• Astronomers despaired of finding Earth-like planets orbiting other stars. Now we have catalogued a zoo of planetary types: hot jupiters, super-Earths, diamond worlds, blast furnace bodies with vaporized iron for clouds, and others. Nothing with green plants and animals yet, but a lot of interesting geology and chemistry.

The heavens have done nothing but confound expectations. So I can get a little excited reading about a phosphorus atom substituting for the nitrogen in ammonia. But I’m not ready to set solar sail for Venus just yet.

Planetary scientist Sara Seager:

This is an astonishing and ‘out of the blue’ finding. It will definitely fuel more research into the possibilities for life in Venus’s atmosphere.

In 1962, the Mariner 2 probe confirmed that the surface of Venus was too hot for Earth life–800°F. Later robotic explorers found the air there laced with sulfuric acid. Surfaced landers were crushed by the thick atmosphere, corroded by acid, and melted in the heat. If there was a way for life to float a few dozen miles above the surface, it might survive. But how would it get there in the first place?

We’ve also detected phosphine in the atmospheres of the giant planets Jupiter and Saturn. Is that a sign of life? Or just a high-temperature phenomenon not yet understood.

More study needed. If I were a bettor, I’d put my chips not on biology, but on chemistry.