Are there any positive aspects to volcanoes? They are unpredictable, dangerous, and aggressive. Volcanoes often cause a nuisance for contemporary people, but they may also sometimes be dangerous and provide an amazing visual show.
However, if there are enough of them, and if they are strong and persistent, they have the potential to destroy the planet where they originate.
Modern-day Venus is a scorching wasteland. The temperature exceeds 464 °C (850 °F, 737 °K), which is hot enough to melt lead, as readers of Universe Today are aware (and spacecraft).
Due to Venus' harsh environment, only four of the missions Russia launched to the planet's surface were able to send photographs before failing.
But Venus in the present day can be quite different from Venus in the past. According to some study, the atmosphere of old Venus was comparable to that of the early Earth.
There was also a chance that the planet's surface had a significant amount of water. There may have once been primitive life on Venus, but the data is still insufficient to confirm or deny that.
According to recent research, the planet's current state may have been changed throughout time by large-scale volcanic eruptions. Volcanoes were the end of primitive life on old Venus.
The research demonstrates how important volcanic activity has been in molding Earth's habitability as well as how Earth nearly escaped Venus' destiny.
The research was published in The Planetary Journal under the title "Large-scale Volcanism and the Heat Death of Terrestrial Worlds." The primary author is Dr. Michael J. Way from NASA's Goddard Institute. The way has been studying Venus for many years and has written and co-written numerous studies on the planet, including its potential for ancient habitability.
In a news statement reporting the work, Way said, "By comprehending the record of big igneous provinces on Earth and Venus, we may assess whether these occurrences may have created Venus' current condition."
Throughout Earth's history, there have been extended periods of continuously occurring volcanic eruptions. The evidence for these eras, which may endure hundreds of thousands or even millions of years, are known as Large Igneous Provinces (LIPs).
More than 100,000 cubic kilometers of rock may be deposited on the surface by LIPs. That would bury Texas a half-mile under the surface. We are aware of several LIPs on Earth, and we also know that throughout the last 500 million years, they have often occurred along with climatic change and major extinctions.
The research hypothesizes that Venus' current atmosphere, with its very high temperatures and pressures, was formed by large volcanic eruptions of its own. More particular, it claims that a runaway greenhouse effect was produced by powerful outbursts over a timescale of only one million years.
When an atmosphere blocks a planet's heat from flowing into space, the runaway greenhouse effect occurs. Extreme temperatures increase because there is no way to cool down, similar to a greenhouse that has all of its vents closed.
Venus seems to lack plate tectonics, which exacerbates the planet's greenhouse effect. The periodic opening of the mantle blanket caused by plate tectonics on Earth enables heat from the planet's interior to reach the surface.
Through weathering and subduction, it also removes carbon dioxide from the atmosphere and incorporates it into rock.
According to this research, our world has gone through five catastrophic extinctions, and each one was brought on by an increase in volcanic activity. (Some experts claim that a sixth mass extinction is now underway as a result of the increasing species loss brought on by human activities.)
The Permian-Triassic extinction that killed out the dinosaurs was mostly caused by the Chicxulub impact event, although volcanic activity also contributed. Volcanic activity has been the primary cause of extinctions on Earth, despite the fact that the Chicxulub dinosaur extinction is well-known and has received significant popularization.
Volcanic eruptions that were enormous and ongoing had a terrible impact on life on Earth. However, it always bounced back, and the volcanoes never set off a greenhouse effect that still affects Venus today. What's the distinction?
One factor was the size of the eruptions. Rock from volcanic eruptions that has hardened covers 80% of Venus' surface. Sulfur in the air is another indicator of intense volcanic activity. Additionally, Venus' surface contains fewer craters than anticipated, which suggests that there has been a lot of volcanic activity in the last few hundred million years.
But everyone should feel uneasy after reading the research. Earth has escaped the runaway greenhouse effect, although it may have been by a hair's breadth.
Because craters disappear, it is difficult to unravel the history of volcanism, impacts, and extinctions throughout Earth's history. Although it's a challenging endeavor, scientists are working to understand the circumstances in the Earth's mantle that cause LIPs.
On a geological time scale, the magmatic episodes that produce LIPs are usually brief, lasting fewer than 5 million years. A sequence of pulses spread out over a few tens of millions of years is another possibility. The chemicals they release into the atmosphere are what cause extinctions, even though the fact that they force a lot of rock onto the surface.
Sulfur dioxide (SO2) is added to the warming caused by enormous amounts of CO2 in the atmosphere. However, only in trace concentrations can toxic substances like carbon monoxide (CO) and hydrogen sulfide (H2S) originate from eruptions.
Because Venus and Earth are "sister planets," the volcanism on one planet is identical to the other. They are both rocky planets in the inner Solar System that are rather similar in size.
However, the crucial characteristic that unites them in terms of volcanism is their mass makeup. They are quite similar in composition since they were created in the same area of the Solar System.
Based on what is known about Earth's volcanic activity and LIPs, the authors of this research used random simulations to reconstruct Earth's volcanic history. In one method, the authors "create a cautious estimate of the rate of occurrence of sets of near-simultaneous LIPs (pairs, triplets, and quartets) in a random history statistically similar to Earth's."
We discover that LIPs closer in time than 0.1-1 million years are probable; noticeably, this is a shorter time than the duration over which terrestrial LIP environmental impacts are known to endure.
This implies that LIP events occur simultaneously, and before the earth can absorb the CO2 from one event that was released into the atmosphere, another is actively releasing more. If you combine enough of them, the runaway greenhouse effect results. Separate LIPs at various locations around the world, even under the sea, increase the impact.
Their study's main focus is on unpredictability Are LIPs causally connected to one another? This is significant because a variable LIP rate raises the possibility of concurrent or overlapping occurrences, which would support a runaway greenhouse effect.
The authors ask "How would variation in the LIP rate over time influence the probability of simultaneous events?"
"The likelihood of concurrent incidents is higher than it would be at normal rates during periods of heightened rate. On the other hand, this chance is reduced in comparison to the average during periods of the lower rate. Which of these impacts is predominant is not immediately apparent."
"We discover that there is a 30% chance that the biggest LIP in known Earth history will coincide with an event of comparable proportions (in the area). If terrestrial planets have Earth-like geochemistries and mantle convection dynamics, then several simultaneous LIPs may be significant drivers of the change from a calm livable surface to a hothouse state "the report asserts.
Everything diverges at a certain point. Our knowledge of Venus' LIPs is far from being as thorough and dependable as that of Earth's. However, the study demonstrates that, even in the absence of precise information, it is plausible that Venus experienced overlapping LIPs that contributed to its demise.
Thankfully, planned missions to Venus will provide this investigation with improved data.
NASA is building an orbiter for the Venus VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy) mission. It will be a three-year mission to study Venus' surface in high resolution using radar and near-infrared spectroscopy; the launch date is not yet set.
It will include thorough details on the planet's impact history, volcanism, geochemistry, and other topics.
Although it will also feature an orbiter, the NASA mission DAVINCI (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging) will also have an atmospheric probe. Scientists may begin unraveling the history of Venus once they have more knowledge on the atmosphere and surface of the planet.
DAVINCI's main objective, according to Way, is to pinpoint the history of water on Venus and when it may have vanished in order to shed more light on the planet's climatic history.
In the late 2020s, DAVINCI and VERITAS will both debut, with DAVINCI doing so earlier.
Additionally, the ESA intends to send an orbiter to Venus. EnVision is the name of it, and it ought to debut in the early 2030s. EnVision will likewise examine Venus' atmosphere, will furtgo butobut it willfurthergofurtherfarther by utilizing its sensor suite to look into the inner workings of the planet.
The knowledge of exoplanets will benefit from these findings as well. The study of exoplanets is expanding, and the James Webb Space Telescope is starting to provide greater information on their atmospheres.
Without improved overall models, it will be difficult for scientists to comprehend the JWST results, and a greater comprehension of the history of our sister planet would undoubtedly improve our models for planetary atmospheres.
Venus is far less hospitable for whatever reason, but Earth has stayed livable for billions of years. If primitive, archaic life ever existed on Venus, it is long since extinct.
(I apologize to anyone who believe there is still life in Venus' clouds.)
Volcanic activity undoubtedly played a part in why Earth and Venus were so distinct from one another, even if we may never fully comprehend all the causes. After VERITAS, DAVINCI, and EnVision complete their tasks, we should have a better understanding of Venus' diverging route.
Comments
Post a Comment