For many years, scientists believed that Venus was a quiet, geologically inactive world where major surface changes stopped long ago.
New research now challenges that view, suggesting that Earth’s closest planetary neighbor may still be tectonically active today, with giant rift valleys that formed much more recently than previously thought.
The study, led by researchers at ETH Zurich, was published in the journal Nature Geoscience.
It provides new evidence that Venus may still have an active interior that continues to reshape parts of its surface.
Venus is often called Earth’s “sister planet” because it is similar in size and composition. However, the two worlds are very different.
Venus has surface temperatures hot enough to melt lead, a thick atmosphere filled mostly with carbon dioxide, and crushing air pressure. Unlike Earth, it has no oceans and no plate tectonics like the moving continents that constantly reshape our planet.
Even so, Venus has enormous cracks in its surface known as rift valleys. These features look similar to Earth’s African Rift Valley, where the Earth’s crust is slowly pulling apart.
On Venus, some of these rift systems stretch for as much as 10,000 kilometers, making them some of the largest geological structures on the planet.
Until now, many scientists believed these rifts formed more than 100 million years ago and had remained largely unchanged ever since. That assumption suggested Venus had become mostly inactive.
The ETH Zurich research team decided to test this idea using a new generation of computer simulations. Led by Professor Taras Gerya and master’s student Xi Yang, the researchers created highly detailed three-dimensional models that are much more realistic than previous studies.
Earlier computer models could only simulate Venus in two dimensions and relied on simplified assumptions about how rocks behave. The new model allowed scientists to better recreate how rift valleys actually form and evolve over time.
The simulations revealed that young and active rift valleys develop wide, raised ridges along their edges, known as rift flanks. These ridges are steep and narrow while the rifts are still opening or have only recently stopped moving.
The researchers also found that these rifts may spread much faster than previously believed, widening by about three to ten centimeters each year. Once movement stops, the raised ridges gradually flatten over time as the planet’s crust slowly relaxes.
Unlike Earth, where wind, rain, rivers, and ice wear away mountains through erosion, Venus has no liquid water. Instead, its landscape changes mainly because the crust slowly sinks and settles under its own weight.
To test their findings, the scientists compared their computer simulations with images collected by NASA’s Magellan spacecraft, which mapped most of Venus during its mission in the early 1990s. They found that several Venusian rift valleys still have the wide, steep flanks expected of relatively young geological features.
This close match between the computer models and spacecraft observations suggests that some of these giant rifts may have formed much more recently than scientists once believed. It also supports the idea that Venus still has an active interior capable of driving tectonic activity today.
The discovery comes as interest in Venus continues to grow. NASA and the European Space Agency (ESA) are both preparing new missions that will explore the planet in far greater detail during the coming decade. One of these projects is ESA’s EnVision mission, which is expected to launch in the early 2030s. Researchers from ETH Zurich are helping develop instruments that will study Venus from orbit, examining everything from its surface to its deep interior and upper atmosphere.
The new findings could help scientists identify the most active regions on Venus for future spacecraft to investigate.
Beyond improving our understanding of our neighboring planet, the research may also provide valuable clues about how rocky planets evolve throughout the universe, including distant Earth-like worlds orbiting other stars.
Source: KSR.
