Venus could have active volcanoes as new evidence suggests its lava flows may only be a few years old
The finding regarding Earth's nearest neighbor could help astronomers understand the evolution of planets, say experts
Lava flows on Venus might only be a few years old, suggesting that the planet could have active volcanoes today, making it the only planet in our solar system, other than Earth, with recent eruptions.
Experts say this makes Venus one of the few worlds in our Solar System that has been volcanically active within the last three million years.
The finding could help astronomers understand the evolution of planets like Earth, according to new research led by the Universities Space Research Association (USRA). The study, for example, could help experts understand how planets cool and why the Earth and Venus have active volcanism, but Mars does not.
"If Venus is indeed active today, it would make a great place to visit to better understand the interiors of planets," says Dr. Justin Filiberto, the study’s lead author and a Universities Space Research Association (USRA) staff scientist at the Lunar and Planetary Institute (LPI), in the analysis.
According to the research team, future missions should be able to see these flows and changes in the surface and provide concrete evidence of its activity.
Radar imaging from NASA's Magellan spacecraft in the early 1990s revealed Venus to be a world of volcanoes and extensive lava flows.
In the 2000s, the European Space Agency's (ESA's) Venus Express orbiter shed new light on volcanism on Venus by measuring the amount of infrared light emitted from part of Venus' surface, during its nighttime. These new data allowed scientists to identify fresh versus changed lava flows on the surface of Venus.
"However, until recently, the ages of lava eruptions and volcanoes on Venus were not well known because the alteration rate of fresh lava was not well constrained," says the study published in Science Advances.
The research team studied the hot caustic atmosphere of Venus in the laboratory to investigate how the observed minerals react and change over time.
The experimental results showed that an abundant mineral in basalt — olivine — reacts rapidly with the atmosphere and within weeks becomes coated with the iron oxide minerals – magnetite and hematite. They found that the Venus Express observations of this “change in mineralogy would only take a few years to occur."
Accordingly, says the team, the new results indicate that these lava flows on Venus are very young. This, in turn, would imply that Venus does have active volcanoes.
"Our results indicate that lava flows lacking visible to near-infrared (VNIR) features due to hematite are no more than several years old. Therefore, Venus is volcanically active now," say the researchers in their findings.
They say, "This active volcanism is consistent with episodic spikes of sulfur dioxide in the atmosphere measured by both the Pioneer Venus Orbiter and the Venus Express, which could have been produced by the same eruption that formed the young lava flows."
In 2010, scientists detected clear signs of lava flows on the surface of Venus. The observations revealed that volcanoes on Venus appeared to erupt between a few hundred years to 2.5 million years ago, suggesting that the planet may still be geologically active.
A few years later, scientists reported transient spikes in sulfur dioxide in Venus' upper atmosphere, another potential signal of active volcanism.
The 2012 study showed large changes in the sulfur dioxide content of the planet's atmosphere, and one intriguing possible explanation is volcanic eruptions. Results from the long-term study of Venus found evidence of a clear injection of sulfur dioxide into its upper atmosphere.
One possible interpretation, said researchers, is that volcanic activity increased the sulfur dioxide component of the upper atmosphere, although an alternative is that a change in atmospheric circulation dredged up the gas.
Again, in 2015, an international team of scientists found some evidence that Earth's nearest neighbor is volcanically active.
In combing through data from the European Space Agency's Venus Express mission, the scientists found transient spikes in temperature at several spots on Venus’s surface. The hotspots, which were found to flash and fade over the course of just a few days, appeared to be generated by active flows of lava on the surface.
The hotspots turned up in thermal imaging taken by the Venus Express spacecraft's Venus Monitoring Camera. The data showed spikes in temperature of several hundred degrees Fahrenheit in spots ranging in size from 1 square kilometer to over 200 kilometers.
The spots were clustered in a large rift zone called Ganiki Chasma. Rift zones are formed by stretching of the crust by internal forces and hot magma that rises toward the surface, said the study.