New paper thinks looking beyond deadly Venus to find life in the universe

A new paper argues that uninhabitable Venus offers important lessons about the potential for life on other planets, despite surface temperatures hot enough to melt lead, lava-spewing volcanoes and fluffy clouds of sulfuric acid.

“We often assume that Earth is a model of habitability, but if you think about the planet in isolation, we don’t know where the boundaries and limits are,” said Stephen Kane, an astrophysicist at the University of California, Riverside and lead author on the paper. . “Venus gave us this.”

Published in the magazine today natural astronomy, a paper that brings together much of what is known about Earth and Venus. It also describes Venus as an anchor point from which scientists can better understand the conditions that make life impossible on planets around other stars.

Earth and Venus have some similarities, although it also has a pressure-cooker-like atmosphere that could crush humans instantly. Their masses and radii are roughly the same. Given the close proximity to the planet, one would naturally wonder why things are so different on Earth.

Many scientists believe that insolation flux (the amount of energy Venus receives from the sun) caused a runaway greenhouse effect that destroyed the planet.

“If you consider that Earth receives 100 percent of the solar energy, Venus collects 191 percent. A lot of people think that’s why the results for Venus are different,” Kane said. “But wait. Venus doesn’t have moons, which gives Earth things like tides and affects the amount of water here.”

In addition to some known differences, more NASA missions to Venus will help eliminate some of the unknowns. Scientists don’t know how big its core is, how it reaches its current relatively slow rotation rate, how its magnetic field changes over time, or anything about the chemical composition of the lower atmosphere.

“Venus has no detectable magnetic field. This may be related to the size of its core,” Kane said. “Core dimensions also give us information about how the planet cools itself. Earth has a mantle that circulates heat from its core. We don’t know what’s going on inside Venus.”

The interior of an Earth-like planet also affects its atmosphere. This is the case on Earth, where our atmosphere is largely the result of volcanic eruptions.

NASA does plan two missions to Venus by the end of this decade, and Kane is assisting with both missions. The Da Vinci mission will probe the acid-filled atmosphere to measure noble gases and other chemical elements.

“Da Vinci will measure the atmosphere from top to bottom. This will really help us build new climate models and predict such atmospheres elsewhere, including here on Earth as we continue to increase the amount of carbon dioxide₂,” Kane said.

The VERITAS mission, led by NASA’s Jet Propulsion Laboratory, will not land on the surface, but it will allow scientists to create detailed 3D reconstructions of the landscape, revealing whether the planet has active plate tectonics or volcanoes.

“Currently, our map of the Earth is very incomplete. Knowing how active the surface is is very different from knowing how it changes over time. We need both kinds of information,” Kane said.

Ultimately, the paper advocates for such a Venus mission for two main reasons. One is the ability to use Venus with better data to ensure that inferences about life on distant planets are correct.

“One of the sobering parts of the search for life elsewhere in the universe is that we will never get live data on exoplanets. We won’t go there, land or measure them directly,” Kane said.

“If we thought another planet had life on its surface, we might never know we were wrong and we would be dreaming of a lifeless planet. We can only correct this through appropriate means.” Learn what we can visit The Earth-sized planet, Venus, gives us this opportunity.

Another reason to study Venus is that it provides a preview of Earth’s future.

“One of the main reasons to study Venus is our sacred duty as guardians of this planet to protect its future. My hope is that by studying the processes that gave rise to today’s Venus, especially if Venus had a more benign past It’s been destroyed now, but we can learn from it, it’s just a matter of how and when.