Named for the ancient goddess of fertility, the planet Venus could not be more hostile to life as we know it. Aside from being the hottest planet in the Solar System, Venus has also an atmosphere that is 92 times denser than Earth’s, and regularly experiences sulfuric acid rain. But as we’ve learned from multiple surveys, Venus was once a much milder climate and even had vast oceans on its surface.
For astronomers and geologists alike, the burning question is, how much of its water did Venus hold onto during this massive transition? According to research presented by Moa Persson of the Swedish Institute of Space Physics (IRF), Venus actually retained most of its water over the past 4 billion years. Contrary to what researchers previously thought, Venus lost only a small amount of its water to a runaway Greenhouse Effect.
In September, a team of scientists reported finding phosphine in the upper atmosphere of Venus. Phosphine can be a biomarker and is here on Earth. But it’s also present on Jupiter, where it’s produced abiotically. The discovery led to conjecture about what kind of life might survive in Venus’ atmosphere, continually producing the easily-degraded phosphine.
The authors of that study were circumspect about their own results, saying that they hope someone can determine a source for the phosphine, other than life.
Now a new study says that the original phosphine detection is not statistically significant.
Does it feel like all eyes are on Venus these days? The discovery of the potential biomarker phosphine in the planet’s upper atmosphere last month garnered a lot of attention, as it should. There’s still some uncertainty around what the phosphine discovery means, though.
Now a team of researchers claims they’ve discovered the amino acid glycine in Venus’ atmosphere.
The discovery of phosphine in Venus’ atmosphere has generated a lot of interest. It has the potential to be a biosignature, though since the discovery, some researchers have thrown cold water on that idea.
But it looks, at least, like the discovery is real, and that one of NASA’s Pioneer spacecraft detected the elusive gas back in 1978. And though it’s not necessarily a biosignature, the authors of a new study think that we need to rethink the chemistry of Venus’ atmosphere.
The detection of phosphine in Venus’ atmosphere was one of those quintessential moments in space science. It was an unexpected discovery, and when combined with our incomplete understanding of planetary science, and our wistful hopefulness around the discovery of life, the result was a potent mix that lit up internet headlines.
As always, some of the headlines were a bit of an over-reach. But that’s the way it goes.
At the heart of it all, there is compelling science. And the same, overarching question that keeps popping up: Are we alone?
Ever since NASA’s Magellan orbiter was able to peak beneath Venus’ dense cloud layer and map out the surface, scientists have puzzled over the planet’s geological history. One of the greatest mysteries is the role volcanic activity has played in shaping Venus’ surface. In particular, there are what is known as “tesserae,” tectonically deformed regions on the surface that often stand above the surrounding landscape.
These features comprise about 7% of the planet’s surface and are consistently the oldest features in their immediate surroundings (dating to about 750 million years ago). In a new study, an international team of geologists and Earth scientists showed how a significant portion of these tesserae appear to be made up of layered rock, which is similar to features on Earth that are the result of volcanic activity.
Last week, an incredible announcement was made about the search for extraterrestrial life: Phosphine gas detected in the clouds of Venus – a potential indicator of life or “biosignature.” Now some gases might be a false positive for biosignatures because they can be created by other chemical processes on a planet like photochemical processes in the atmosphere or geological processes beneath the surface that create a given gas. For example, methane can also be a biosignature, and we’ve been hunting it down on Mars, but we know that methane can also be created geologically. Finding phosphine in Venusian clouds is truly remarkable because we don’t presently know of any way to create phosphine abiotically or without life being a part of the equation. Question is – how much life??
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.
Scientists have learned a lot about the atmospheres on various worlds in our Solar System simply from planetary sunrises or sunsets. Sunlight streaming through the haze of an atmosphere can be separated into its component colors to create spectra, just as prisms do with sunlight. From the spectra, astronomers can interpret the measurements of light to reveal the chemical makeup of an atmosphere.