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Venus May Have Been the First Habitable Planet In Our Solar System, Study Suggests (theguardian.com)
An anonymous reader quotes a report from The Guardian: Venus is often referred to as Earth's evil twin, but conditions on the planet were not always so hellish, according to research that suggests it may have been the first place in the solar system to have become habitable. The study, due to be presented this week at the at the American Astronomical Society Meeting in Pasadena, concludes that at a time when primitive bacteria were emerging on Earth, Venus may have had a balmy climate and vast oceans up to 2,000 meters (6,562 feet) deep. Michael Way, who led the work at the Nasa Goddard Institute for Space Studies in New York City, said: "If you lived three billion years ago at a low latitude and low elevation the surface temperatures would not have been that different from that of a place in the tropics on Earth," he said. Crucially, if the calculations are correct the oceans may have remained until 715m years ago -- a long enough period of climate stability for microbial life to have plausibly sprung up. "The oceans of ancient Venus would have had more constant temperatures, and if life begins in the oceans -- something which we are not certain of on Earth -- then this would be a good starting place," said Way. With an average surface temperature of 462C (864F), Venus is the hottest planet in the solar system today, thanks to its proximity to the sun and its impenetrable carbon dioxide atmosphere, 90 times denser than Earth's. At some point in the planet's history this led to a runaway greenhouse effect. Way and colleagues simulated the Venusian climate at various time points between 2.9 billion and 715 million years ago, employing similar models to those used to predict future climate change on Earth. The scientists fed some basic assumptions into the model, including the presence of water, the intensity of the sunlight and how fast Venus was rotating. In this virtual version, 2.9 billion years ago Venus had an average surface temperature of 11C (52F) and this only increased to an average of 15C (59F) by 715m years ago, as the sun became more powerful. Details of the study are also published in the journal Geophysical Research Letters.
I'm making the popcorn right now.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
reminds me of the one-shot manga Hotel (where global warming on Earth turns it basically into Venus).
But Venus inhabitants smoked too much, this explains the CO2 excess...
Now we can see what happened when Venusian politicians used climate change as a political tool.
My ism, it's full of beliefs.
Isn't it 'Venerian' not 'Venusian'? After all we don't say 'Marsian'.
-- Ed Avis ed@membled.com
(just fire some fukken lasers at Jupiter, maybe we might even make a minor star in a few billion years)
Fraid not. Jupiter is too small to sustain fusion temperatures at its core. If you fire lasers at it, you'll heat it up, and increase its volume. You'd make it *less dense*. If you somehow made Jupiter more massive, it would become smaller, and eventually yeah it'll be a red dwarf. But you need about 8-10 times the current mass.
So yeah - that plan wouldn't work.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
No, Venus was first, and had a thriving civilisation. At first, they never bothered to explore the rest of the solar system because it didn't make economic sense. When it became clear that their planet was rapidly warming up and would soon become uninhabitable, they made a last ditch effort to migrate to earth. The colony did not survive, but their bacteria and some other simple life forms did. The rest is history.
Except for a technological achievement that led to their utter and total extinction: the development of the Galaxy Note 7. If it weren't for the recall that is in effect today, we would have hurtled on toward our self-destruction. A disaster of Bibilical proportions.
WARNING: Smartphones have side effects--most of them undocumented.
So if Earth's climate changes too much, we'll eventually have an atmosphere 90 times as denser ? How interesting... It's amazing how such thing as a runaway greenhouse effect never happened during 4.5 billion years of our fragile planet existence...
"Like Ringo Said"
Wrong Beatle
Venus and Mars was the title track or the 1975 album by Paul Mcartney and Wings
If we can build (presumably) ships that are sealed enough to protect us from the great vacuum that is space, and that can last years in the great nothingness that is space, then we can certainly build habitats here on earth to survive the most extreme changes in climate.
At the end, a spaceship that will take us to another solar system is essentially a huge dwelling that contains everything we will need to restart life on another planet - there is no guarantee that we will find the necessary building blocks there. So we would not only have to take our food, but the plants that can produce the food, the animals that would provide meat, the bacteria that all plants and animals depend on, the birds and the bees - everything needed to bootstrap another earth.
And this assumes that we can find a planet that contains the right ingredients to support life. All the minerals that are necessary to grow life e.g. the right quantities of magnesium to create chlorophyll. If we were doing this, we might need a thousand years to get it right.
Put it another way, if you were a weary space traveller, and you happened upon an earth who surface had heated to, say, 25 degrees on average, would you settle there and try to make it work, or would you travel on?
The solar system is comprised of the sun, plus miscellaneous junk (0.14% the mass of the sun).
If you want to be more precise, the solar system is comprised of the sun-Jupiter binary system (barycentre outside the sun), plus miscellaneous junk (~30% the mass of Jupiter)
If you want to be more precise, the solar system is comprised of the sun, the gias giants, plus miscellaneous junk
If you want to be more precise, the solar system is comprised of the sun, the gas giants, the ice giants, and miscellaneous junk
No, the mass for making Jupiter a star just isn't here, unless you want to take it from the sun (which actually might be nice - extending its lifespan). Easier might be selective removal of gases from Jupiter - remove part of the 1H and 4He but leave the 2H, and you might be able to get it up to a sufficient D-D reaction rate to be considered a star (although I haven't done any simulations; the compression might be too low).
The internet is not a series of tubes. It's more like a net. Or a network of computers. Or an internet.
I was inclined to poo-poo this paper but it does make an interesting observation. Venus has a crushingly dense atmosphere now (mostly CO2) but it is 3.5% Nitrogen. The authors point out that the weight of Venus's Nitrogen is actually comparable to the Earth's (10^19 kg). The field of astrobiology runs off the rails in its endless focus on carbon and water when what you also need is nitrogen (and reduced at that). Since the sun was once cooler and Venus was once wetter there is good reason to investigate the possibility that conditions were once life favorable.
Too bad it is most assuredly dead now.
Hang on though, we're working very hard to catch up and maybe we'll be #1 soon.
I'm a 2000 man.
This whole article and the research conducted to produce it are from Uranus
Although that's certainly how some people will try to spin it. Venus' atmosphere is theorized to have begun much like Earth's. The crucial difference was its proximity to the sun caused its water to mostly turn into vapor, instead of remain as a liquid. This (1) contributed to the greenhouse effect - water vapor is the biggest greenhouse gas contributor on Earth despite only a tiny fraction of our water being in vapor form, and (2) rose above heavier CO2 thus shielding it from being lost into space or being broken apart into its elements by solar radiation (Venus has almost no magnetosphere to protect it).
So Venus' CO2 was allowed to build up instead of being lost to space, eventually leading to the enormous pressures Venus has today. Mars's atmosphere has a similar composition (both are 96% CO2), but due to its weaker gravity and lack of water vapor, most of Mars' CO2 was lost into space giving Mars a surface atmospheric pressure only 0.6% that of Earth's. Venus' surface pressure by contrast is 92 times Earth's atmospheric pressure at sea level. CO2's critical point is at 73.9 bar (atmospheres) and 31 C, above which the difference between the gas and liquid phases disappears. So the CO2 "atmosphere" on Venus' surface is more like a sea of CO2 fluid (the Venera landers didn't even use parachutes for the final descent - they gently floated down using nothing but hull drag). You basically have the greenhouse effect of the CO2 gas, compressed into the higher density of liquid CO2. All made possible by excess water vapor early in Venus' early history.
Earth's early atmosphere was also nearly the same as on Mars and Venus. But Earth retained liquid water, which was able to dissolve most of the CO2, creating the "habitable" conditions for life we have today. So it's actually liquid vs gaseous water which is the key difference, not CO2 levels. In fact Venus' present atmosphere is theorized to actually be much more hospitable. In the past when water vapor was still present, temperatures there were probably twice what they are today.