Venus and Earth have several things in common. Both are terrestrial planets composed of silicate minerals and metals that are differentiated between a rocky mantle and crust and a metal core. Like Earth, Venus orbits within our Sun’s circumsolar habitable zone (HZ), though Venus skirts the inner edge of it. And according to a growing body of evidence, Venus has active volcanoes on its surface that contribute to atmospheric phenomena (like lightning). However, that’s where the similarities end, and some rather stark differences set in.
In addition to Venus’ hellish atmosphere, which is about 100 times as dense as Earth’s and hot enough to melt lead, Venus has a very “youthful” surface. Compared to other bodies in the Solar System (like Mercury, the Moon, and Mars), Venus’ surface retains little evidence of the many bolides impacts it experienced over billions of years. According to new research from the Southwest Research Institute (SwRI) and Yale University, this may result from bolide impacts that provided a high-energy, rejuvenating boost to the planet in its early years.
Using archival radar images taken in the 1990s by NASA’s Magellan spacecraft, scientists have found evidence of recent active volcanism on Venus. The images revealed a volcanic vent that changed shape and increased significantly in size over an eight-month period.
The scientists say their findings confirm long-held suspicions that the planet, which is known to have a very geologically young surface and evidence of past volcanic eruptions, is still active today.
“We made the discovery in the most likely place that there should have been new volcanism,” said Robert Herrick, a geophysicist at the University of Alaska Fairbanks, speaking at a briefing on March 15, 2023 from the Lunar and Planetary Science Conference in Texas. “Extrapolating from a data set of one for an entire planet could be dangerous, but most scientists would say it’s pretty good evidence that being able to catch an eruption in an eight-month time frame means that others are taking place as well. It confirms there is modern geological activity on Venus.”
We’re lucky to have a neighbour like Venus, even though it’s totally inhospitable, wildly different from the other rocky planets, and difficult to study. Its thick atmosphere obscures its surface, and only powerful radar can penetrate it. Its extreme atmospheric pressure and high temperatures are barriers to landers or rovers.
It’s like having a mysterious exoplanet next door.
While Earth and Venus are approximately the same size and both lose heat at about the same rate, the internal mechanisms that drive Earth’s geologic processes differ from its neighbor. It is these Venusian geologic processes that a team of researchers led by NASA’s Jet Propulsion Laboratory (JPL) and the California Institute of Technology hope to learn more about as they discuss both the cooling mechanisms of Venus and the potential processes behind it.
In a recent paper accepted to Contemporary Physics, a physicist from Imperial College London uses past missions and recent findings to encourage the importance of searching for life in the atmosphere of the solar system’s most inhospitable planet, Venus. This comes as a 2020 announcement claimed to have discovered the presence of phosphine in Venus’ atmosphere followed by follow-up observations from NASA’s recently-retired SOFIA aircraft in late 2022 that refuted it. Despite this, Dr. David Clements, who is a Reader in Astrophysics in the Department of Physics at Imperial College London, recently told Universe Today that “there is something odd going on in the atmosphere of Venus.”
Is there anything good about volcanoes? They can be violent, dangerous, and unpredictable. For modern humans, volcanoes are mostly an inconvenience, sometimes an intriguing visual display, and occasionally deadly.
But when there’s enough of them, and when they’re powerful and prolonged, they can kill the planet that hosts them.
The planet Venus is one of the most inexplainable and mysterious planetary objects in our solar system as its surface is beyond inhospitable for us fragile humans with temperatures at a searing 475 degrees Celsius (900 degrees Fahrenheit) and surface pressures more than 90 times that of Earth. However, its atmosphere is quite a different story as its temperature varies considerably ranging from -143 degrees Celsius (-226 degrees Fahrenheit) at night to 37 degrees Celsius (98 degrees Fahrenheit) in the daytime, and varies based on altitude, as well.
It’s an exciting time to be a Venus watcher. Our sister planet, which has been the target of only one mission since the 1980s, is now the focus of not one, not two, but three missions from NASA and ESA. Combined, they promise to give the closest look ever at the Morning Star, and some of the processes that might have made such a similar world so different from our own.
NASA’s planetary science program is making a big bet on Venus, after decades of putting its chips on Mars in the search for hints of past or present life out there in the solar system.
The bet comes in the form of a double dose of development funding for Discovery Program missions, amounting to as much as $1 billion. Both DAVINCI+ and VERITAS were selected from a field of four finalists in a competitive process — leaving behind missions aimed at studying Jupiter’s moon Io and Neptune’s moon Triton.
“These two sister missions are both aimed to understand how Venus became an inferno-like world capable of melting lead at the surface,” NASA Administrator Bill Nelson said June 2 in his first “State of NASA” address. “They will offer the entire science community the chance to investigate a planet we haven’t been to in more than 30 years.”
Lessons from Venus, which underwent a runaway greenhouse effect early in its existence, could improve scientists’ understanding of our own planet’s changing climate. The missions could also address one of the biggest questions about the second rock from the Sun: whether life could exist in the upper reaches of its cloud layer.
The discovery of phosphine in the upper clouds in Venus’ atmosphere has generated a lot of excitement. On Earth, phosphine is produced biologically, so it’s a sign of life. If it’s not produced by life, it takes an enormous amount of energy to be created abiologically.
On other planets like Jupiter, there’s enough energy to produce phosphine, so finding it there isn’t surprising. But on a small rocky world like Venus, where there’s no powerful source of energy, its existence is surprising.