NASA climate modeling suggests Venus may have been habitable

NASA climate modeling suggests Venus may have been habitable
Observations suggest Venus may have had water oceans in its distant past. A land-ocean pattern like that above was used in a climate model to show how storm clouds could have shielded ancient Venus from strong sunlight and made the planet habitable. Credit: NASA

Venus may have had a shallow liquid-water ocean and habitable surface temperatures for up to 2 billion years of its early history, according to computer modeling of the planet's ancient climate by scientists at NASA's Goddard Institute for Space Studies (GISS) in New York.

The findings, published this week in the journal Geophysical Research Letters, were obtained with a model similar to the type used to predict future climate change on Earth.

"Many of the same tools we use to model climate change on Earth can be adapted to study climates on other planets, both past and present," said Michael Way, a researcher at GISS and the paper's lead author. "These results show ancient Venus may have been a very different place than it is today."

Venus today is a hellish world. It has a crushing carbon dioxide atmosphere 90 times as thick as Earth's. There is almost no . Temperatures reach 864 degrees Fahrenheit (462 degrees Celsius) at its surface.

Scientists long have theorized that Venus formed out of ingredients similar to Earth's, but followed a different evolutionary path. Measurements by NASA's Pioneer mission to Venus in the 1980s first suggested Venus originally may have had an ocean. However, Venus is closer to the sun than Earth and receives far more sunlight. As a result, the planet's early ocean evaporated, water-vapor molecules were broken apart by ultraviolet radiation, and hydrogen escaped to space. With no water left on the surface, carbon dioxide built up in the atmosphere, leading to a so-called runaway greenhouse effect that created present conditions.

Previous studies have shown that how fast a planet spins on its axis affects whether it has a habitable climate. A day on Venus is 117 Earth days. Until recently, it was assumed that a thick atmosphere like that of modern Venus was required for the planet to have today's slow rotation rate. However, newer research has shown that a thin atmosphere like that of modern Earth could have produced the same result. That means an ancient Venus with an Earth-like atmosphere could have had the same rotation rate it has today.

Another factor that impacts a planet's climate is topography. The GISS team postulated ancient Venus had more dry land overall than Earth, especially in the tropics. That limits the amount of water evaporated from the oceans and, as a result, the by water vapor. This type of surface appears ideal for making a planet habitable; there seems to have been enough water to support abundant life, with sufficient land to reduce the planet's sensitivity to changes from incoming sunlight.

Way and his GISS colleagues simulated conditions of a hypothetical early Venus with an atmosphere similar to Earth's, a day as long as Venus' current day, and a shallow ocean consistent with early data from the Pioneer spacecraft. The researchers added information about Venus' topography from radar measurements taken by NASA's Magellan mission in the 1990s, and filled the lowlands with water, leaving the highlands exposed as Venusian continents. The study also factored in an ancient sun that was up to 30 percent dimmer. Even so, ancient Venus still received about 40 percent more sunlight than Earth does today.

"In the GISS model's simulation, Venus' slow spin exposes its dayside to the sun for almost two months at a time," co-author and fellow GISS scientist Anthony Del Genio said. "This warms the surface and produces rain that creates a thick layer of clouds, which acts like an umbrella to shield the surface from much of the solar heating. The result is mean climate temperatures that are actually a few degrees cooler than Earth's today."

The research was done as part of NASA's Planetary Science Astrobiology program through the Nexus for Exoplanet System Science (NExSS) program, which seeks to accelerate the search for life on planets orbiting other stars, or exoplanets, by combining insights from the fields of astrophysics, planetary science, heliophysics, and Earth science. The findings have direct implications for future NASA missions, such as the Transiting Exoplanet Survey Satellite and James Webb Space Telescope, which will try to detect possible habitable planets and characterize their atmospheres.


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Simulations suggest Venus may have once been able to support life

More information: Was Venus the First Habitable World of our Solar System? Geophysical Research Letters, 11 August 2016ю DOI: 10.1002/2016GL069790
Journal information: Geophysical Research Letters

Citation: NASA climate modeling suggests Venus may have been habitable (2016, August 11) retrieved 25 June 2019 from https://phys.org/news/2016-08-nasa-climate-venus-habitable.html
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Aug 11, 2016
Re: "Scientists long have theorized that Venus formed out of ingredients similar to Earth's, but followed a different evolutionary path."

Let nobody forget that Venus is one of the most important archetypes in the first stories that people told. It was so feared by the Mayans that they constructed a calendar to try to predict its future state.

Why would anybody fear Venus? There's without a doubt more to this story than a scientific model can explain.

Aug 11, 2016
Sure. Almost anyone can tell you what was happening on another planet 2 billion years ago. Piece of cake. A PS3 can do it.

Aug 13, 2016
There are two serious flaws with this study. First and foremost, they are using Earth-based climate models, which we know from decades of experience that they have never even been close to accurate. Second, when the sun was 30% less luminous than it is today, Venus was also considerably closer to the sun than it is now due to the inward migration of Jupiter. They also fail to factor in the huge number of volcanoes that have been, and still are, raging on Venus' surface creating the greenhouse gases that are causing the planet to bake. It is a completely ludicrous suggestion that Venus could have ever had liquid water on its surface, much less have ever been habitable.

Aug 13, 2016
There are two serious flaws with this study. First and foremost, they are using Earth-based climate models, which we know from decades of experience that they have never even been close to accurate. Second, when the sun was 30% less luminous than it is today, Venus was also considerably closer to the sun than it is now due to the inward migration of Jupiter. They also fail to factor in the huge number of volcanoes that have been, and still are, raging on Venus' surface creating the greenhouse gases that are causing the planet to bake. It is a completely ludicrous suggestion that Venus could have ever had liquid water on its surface, much less have ever been habitable.

That's quite a pile of excrement, rolled in bullocks and then dipped in fabrication! You managed to get every single thing wrong! That's quite an accomplishment, I must say.

Aug 13, 2016
@HA,
Let nobody forget that Venus is one of the most important archetypes in the first stories that people told.


How do you know? What stories were being told around Palaeolithic campfires? You haven't a clue, until the quite recent invention of writing. Even then, what was written down had almost certainly been passed down for many, many generations. And changed out of all recognition in the process. All they can tell us about, is what people believed in those times. Given the amount of b*llocks that people still believe in today, then it is best to try not to over- or misinterpret them to create scientifically illiterate and impossible rubbish, such as that written by Velikovsky and Talbott.

Aug 13, 2016
Why would anybody fear Venus?
@hannes/chris reeve TROLL
1- why would anyone fear wolves in the US? (because of the power of myth and delusion)
why would anyone fear a "god" that can't be proven to exist? (because of the power of myth and delusion)

2- just because you believe something to be true doesn't mean it is

3- repeating a lie (especially about myths being factually accurate) doesn't make it more valid nor does it give it substance

any "researcher" should know the difference between fact, myth and what constitutes evidence
https://en.wikipe...evidence

your claims are called "false claims", or more colloquially, blatant lies
http://www.auburn...ion.html

stop proselytizing your religious beliefs without evidence: science lives on evidence, just like research requires evidence, or at least reputable references

Aug 13, 2016
That's quite a pile of excrement, rolled in bullocks and then dipped in fabrication!

That's a perfect description of the "scientific paper" above. Sci-fi journalism written by fanciful computer gamers.

Aug 13, 2016
description of the "scientific paper"
@cantthink
wow... imagine that: you posted a false claim because your delusional religious opinion won't allow you to actually see evidence that refutes your belief
http://www.auburn...ion.html

https://en.wikipe...iki/Bias

where is your evidence?

oh wait... that's right! you believe in the con men running your cult, therefore your evidence is going to be quotes, lies, and more opinion wrapped in delusional ranting about how only your evidence can be considered "real" despite the overwhelming evidence that proves you're in a cult of religious pseudoscience proselytizing eu dogma over validated proof

Aug 13, 2016
"... mean climate temperatures that are actually a few degrees cooler than Earth's today."


Cool!

Having three potential inhabited and close terrestrials may meant a lot of transpermia events over the 0.5 (3 planets) to 2 (2 planets) billion years that could have happened.

Aug 13, 2016
I think we can kill three trolls - BackBurner, TMGrath, and 85xwindbag - with one stone:

"In November 2004, Climatologists Drew Shindell and Gavin Schmidt of NASA's Goddard Institute for Space Studies, New York, received Scientific American magazine's Top 50 Scientist award.[5]"

[ https://en.wikipe..._Studies ]

Having two of the Top 50 scientists (more or less) in climatology reject all those claims.

And HA is a ridiculous mythologist, without even references this time, so no need for a stone as his ideas was dead on arrival.

Aug 13, 2016
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Aug 13, 2016
This comment has been removed by a moderator.

Aug 14, 2016
That's quite a pile of excrement, rolled in bullocks and then dipped in fabrication!

That's a perfect description of the "scientific paper" above. Sci-fi journalism written by fanciful computer gamers.
And yet, except for skreetching like a little chind that it is somehow wrong and doesn't make sense to you, you have provided exactly nothing to argue the central point, nor the data, nor the extrapolation of the data, nor the conclusion that the data led them to.

So, as usual, the Acolyte just throws around comments that show his Faith, with nary a fact or a data point by which to counter the findings f those who actually go out and do the research. Far easier, apparently, to sit in ones basement typing furiously on a computer about how one Faith should be in the moving tales spun by a lunatic who saw lightning bolts in paintings on cave walls.

You need to update your bible Acolyte, 1984 was 32 years ago.

Aug 14, 2016
Let nobody forget that Venus is one of the most important archetypes in the first stories that people told. It was so feared by the Mayans that they constructed a calendar to try to predict its future state.
There is absolutely no evidence for this. It is a made up construct! If anything, Venus was considered a "good" party, allied with Quetzalcoatl (Quetzalcoatl is a deity known as Kukulcan to the ancient Maya), the patron god of learning and knowledge in the Aztec priesthood. Also known as Tlaloc, Venus was a supreme god of the rains, he was also by extension a god of fertility and of water.

You know NOTHING Lesser Acolyte!

Why would anybody fear Venus? There's without a doubt more to this story than a scientific model can explain.
Probably right, very few feared it. Maybe you should take a minute and learn about it.

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