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New Map Hints At Venus' Wet, Volcanic Past
Matt_dk writes with this excerpt from Space Fellowship: "Venus Express has charted the first map of Venus' southern hemisphere at infrared wavelengths. The new map hints that our neighbouring world may once have been more Earth-like, with a plate tectonics system and an ocean of water. The map comprises over a thousand individual images, recorded between May 2006 and December 2007. Because Venus is covered in clouds, normal cameras cannot see the surface, but Venus Express used a particular infrared wavelength that can see through them."
Venus... Wet... Volcanic... - sounds like the perfect title for some strange alien porn :-)
That title would have been so much better if it was:
"Infrared Scan Of Venus' Southern Regions Hints At Wet, Hot Past"
The new map hints that our neighbouring world may once have been more Earth-like, with a plate tectonics system and an ocean of water.
Yep. Until the Venusians burned all those fossil fuels and released all that CO2....
When I read that title, I thought of the mythological Venus, not the planet. SCNR.
Does molten rock really mean there has to be a volcano? The thermal map shows that some parts get up to 715 K, hot enough to melt lead.
"The Y chromosome is genetic. The odds are very good that if you are male then your father was too." -Internet Commenter
that title sounds so subliminally suggestive, lol
Did you not read that part about how you can't see the surface because of the clouds? Yeah, that's an atmosphere, it's just not a very pleasant one.
Plate tectonics stopped on venus long ago and this lead to overheating which caused a massive planet wide resurfacing and out gassing ever few hundred million years, causing venus to be the craphole it is now. If it had a moon and decent rotation plate techtonics would have likely been persevered. and life may still have been there.
Tsukasa: All I really want, is to be left alone...
Why is that so many people who dream of colonizing other worlds and traveling faster than light rarely leave their own houses?
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So Venus lost it's atmosphere eh? good thing it did because now we can send landers that don't have to worry about the 100X sea level pressures.
Tsukasa: All I really want, is to be left alone...
but i always thought venus was a better target for terraforming
its easier to subtract out of venus' atmosphere than put in mars' atmosphere what isn't there. i didn't say EASY, i said EASIER
some sort of genetically engineered bug that sequesters all of the CO2 and H2SO4, and permanently precipitates it out, preferably leaving O2 and H2O. something that could live on top of the clouds and in them. there's a lot of energy in that atmosphere, and you're closer to the sun... which is actually good: something to work with. rather than being far from the sun and feeble with resources, like mars
again, this is in no way easy, but if we ever reach the technological acumen and sustained effort needed to terraform one of our neighbors, i really think venus is a much better target than mars. more available energy to work with, almost identical gravity profile, and the need to subtract something out of the atmosphere, rather than to somehow create what isn't there, which is a lot easier to do, logically
mars has a long and sustained following and fan base, in science fiction as well as real science, but venus is the real future of mankind's first off-world colonization (besides the moon), if we ever get to that level of sophistication to even consider the possibility
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
There seem to be a high percentage of historically "Wet" satellites in our solar system. Earth,Venus, Mars possibly Europa, Titan....... Are our assumptions about solar system formation and the likely hood of liquid water covered satellites off?
but dry present is discouraging.
weinersmith
Umm... someone correct me, but doesn't Venus have a pretty THICK atmosphere, rather? Just with insane pressure and a composition that would even make smog-accustomed LA residents refuse to take a breath?
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Is it me, or did the "cool" parts of the map look to be over 400C?
Venus is actually quite terra-formable. It does have an atmosphere, an extremely thick one at that, which has caused its high temperature. It also has gravity closer to ours than the moon or Mars. If we could turn the CO2 into O2 and usable carbon (like for soil), we could eventually live on it. Wouldn't be easy, but probably more feasible than terra-forming Mars.
Just because you are wrong and I called you out on it doesn't mean I am a Troll.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
...and the submission's title.
There's a joke here. I just know it...
Think... think... think....
Nope, can't think of one.
I've lost all my marbles except one & It's fun to test angular & centripetal acceleration in my skull
All we need is a wormhole to suck the atmosphere from Venus to Mars and we are all set.
I Am My Own Worst Enemy
Bradbury was right about the wet part at least!
Gravity is a nice thing, but since you eventually want to launch more stuff into space, Mars-like gravity is better than something close to 1g. It allows all the niceties (indoor plumbing, showers, toilets, kitchens, cups of coffee, etc) while still making it much easier to launch something.
If we could turn the CO2 into O2 and usable carbon (like for soil), we could eventually live on it.
Unfortunately, you'll need hydrogen, too, and most of Venus' hydrogen has already escaped into space. Large amounts of nitrogen would be nice, too, which Venus seems to be lacking, too.
Wouldn't be easy, but probably more feasible than terra-forming Mars.
Mars is probably closer to being terraformed now than Venus will be for thousands of years (even if we start working on it now). You could take a walk on Mars in a spacesuit right now, on Venus, you'd be well-done within seconds. A Martian day is about 25 hours, compare that to a few weeks on Venus, with all the associated problems (even if we get rid of the atmosphere, someone on the planet will be in direct sunlight for weeks, and without sunlight for weeks).
The approach for terraforming Venus that sounds most promising to me was to build a giant sunshade, wait until the atmosphere solidifies, and then ship it offworld or shoot it into space. Then crash some comets rich in hydrogen and nitrogen on the planet.
You got me, I wasn't trying to saying Venus didn't have an atmosphere, but its lighter gases (Hydrodren, Helium, Oxygen were all burned and or pull off) do to its close proximity to the sun. Leaving it with the dense gases which it is currently made of (Nitrogen and Carbon dioxide..maybe a little methane, but don't quote me I haven't taken an atronomy class since freshman year of college). So sorry in forgetting to say part of.
Just because you are wrong and I called you out on it doesn't mean I am a Troll.
That technology using some particular wavelength of IT to see through? Do they have any plans to incorporate them into sun glasses?
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Planetary rotation and the presence of moons has nothing to do with plate tectonics. The moon's gravity isn't strong enough to move whole sections of the planet's crust. The direction of plate motion varies from place to place and over time. If it were affected by the Earth's rotation, plates would only move CCW or CW. Plate motion on Earth is powered by mantle convection - magma from the lower mantle rising towards the surface, cooling, sinking back down, heating up, rising, etc. The recycling of magma essentially drags the plates around, like a conveyor belt.
Venus has a kind of tectonic cycle, but it works much differently. Based on the presence and relative age of craters and volcanoes on the surface, Venus seems to undergo catastrophic, global volcanism every 500Ma. This massive periodic volcanism, among other things, replenishes the planet's super-thick CO2 atmosphere. Otherwise, solar winds would have long ago stripped Venus of its atmosphere, since the planet has no significant magnetosphere.
How about bio-engineering some extremophiles to due some conversions for us? Then, when we land, we just release some extremophile-eating microbes to clean up. Then winter comes, and they all freeze to death.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
I wonder how many people will get fired as a result of reading this article, and then googling for "wet venus" at work, and getting NSFW results.
You see? You see? Your stupid minds! Stupid! Stupid!
I like to point out to those people that granite is radioactive and some forms have been shown to give off levels of radon several times higher than the FDA recommends as safe. Then ask how much food they prepare on them.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
I was thinking that too, but can any organism in existence thrive at 422-442 celsius (792F - 828F), consume CO2 and expell O2 at a good speed (approx 25 years?) Can it be bio-engineered? Oh, and we have to keep it dormant for the trip to Venus, have it survive impact, wake up after the trip, then we have to be able to handle it after the work is done.
I call it 'The Aristocrats'
42. It's everywhere!
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don't depend on temperature differences. the only difference between hypothetical terraforming bug #1, functioning at high temp, versus hypothetical terraforming bug #2, functioning at low temp, is that bug #1 will work orders of magnitude faster than bug #2. regardless, we're not going to be terraforming with industrial sized reactors that do depend upon temp differences, but with nanotech, or more likely, genetically engineered critters
furthermore, suncreen with high SPF is the least of your concerns. with no water, nothing on venus exists to lubricate plate tectonics. with no plate tectonics, there is convection in the core, and therefore, no geomagnetic field. meaning venus is being bombarded with cosmic rays and other nasty high energy rays from the sun. i think the order of the day for living on a terraformed venus would be: have a nice fashionable lead umbrella ;-P
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
If we could turn CO2 into useful oxygen and free carbon, don't you think we'd be doing it here on Earth first?
"I guess the moral of the story is, don't paint your airship with rocket fuel." -- Addison Bain
I was wondering what would happen if you placed a mirror in an orbit between the sun and Venus so that the mirror remained between the two at all times (I am sure there is a term for it, geostationary but relative to the sun). Anyhow, if it were a few tens of square miles, would it be able to deflect enough of the sun's energy to bring about an appreciable drop in temperature. My thought is that once you started the cooling, that other processes like thinning of the atmosphere would cause a multiplier effect.
Please feel free to shoot holes in this idea :)
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Plenty of hydrogen in the atmospheric sulfuric acid. Also, a Venusian day is 243 days back here on Earth; this is related to Venus being the only planet to rotate backwards compared to the other planets, probably the result of a collision long ago.
Hail Eris, full of mischief...
E pluribus sanguinem
There is the minor problem of the small fraction sulphuric acid and the small amount of nitrogen. If we really converted all the CO2 to O2 then fires would be a major concern. We would actually need to remove a large fraction of the atmosphere, add nitrogen (or other inert gas), filter out the H2SO4 and also find some way to massively increase the albedo to reduce the far greater heating from the sun. If you can do all of that then you are right - Venus is terraformable. Short of them finding the cure for aging I doubt I'm going to live to see it happen though.
Huh? Venus has a dense atmosphere - much denser than Earth's (something like being under 1km of water at the surface). I believe you meant lost its water, not atmosphere. While Venus is closer to the sun than Earth, it gets about one quarter the sunlight of Mercury yet has a higher maximum surface temperature to to the greenhouse gas effect.
So beyond just the heat, a human would need either liquid breathing or a rigid articulated pressure controlled suit, and liquid breathing has plenty of issues for any long-term use. Something like the Libelle G-suit (body is in a rigid suit immersed in liquid, but still breathing air - the name means Dragonfly in German and is based on them) would probably not work for survival on Venus, but it could be used for higher acceleration to get there (or to Mars).
Hey, Earth had a worm hole until john crichton collapsed, maybe Venus would have one too?
The problem with Venus is that it is closer to the sun. Even if you converted Venus into Earth 2.0 it would almost certainly be too hot to live on. This means that you would need some way to cool the planet significantly as well as shield it better from the increased UV radiation. Not impossible but I'm not so sure it is a better target than Mars. The advantage of Mars is that you can build structures on the surface as a step towards terraforming and build up the process gradually. This is close to impossible on Venus. Mars may have some disadvantages (cooler, lower gravity) but I'm not sure that these are bigger problems than Venus'.
where the temperature is regularly 115 degrees. they do it by just not going outdoors that much and having good ac. so you live indoors on venus, and you have genetically engineered crops that can withstand the high temps and scorching rays (as well as cosmic rays and other nasty high energy rays, since venus has no geomagnetism). you could have some nice architecture with large bay windows, just no skylights ;-P
now compare that limitation with mars, with the very low atmospheric pressure, the much lower gravity, and the bitter cold. you would need a moonsuit to go outside on mars, even a terraformed one, unless you figured out some magical way to bulk up the atmosphere. as opposed to the limitations that most GIs in iraq suffer under on their tour of duties. that would be like going outside on a hypothetical terraformed venus with an atmosphere you would need to precipate and reduce- a hard job, but easier than bulking up mars' atmosphere
furthermore, venus's day is something like 100 earth days long. currently, the temperature is uniform on venus, nightside to dayside, pole to equator, due to the crazy dense atmosphere. but a terraformed venus would definitely exhibit temperature differences like on earth. desert dwellers on earth are familiar with the very hot days and very cold nights. so you'd have a siesta-like culture, where no one would go out in the middle of the night or the the middle of the day (where the "day" is 100 days long), but at dusk and dawn, you would have weeks of pleasant temperatures in between
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
IANAOMS, but I think that for the mirror to be stable at an orbit closer than Venus, it would have to move faster than Venus. If it moved at the same angular velocity as Venus, but was closer in, I think it would be unstable and eventually fall into the Sun. A series of shields in stable orbit around Venus, each a couple of thousand square km, might work better... Cooling the atmosphere is certainly a requirement, but I think that you would need to remove the CO2 before you saw additional benefit. You would also need to remove the SO2 and figure out what to do about the 92 atmospheres of pressure at the surface to make it livable...
Holy shit!!
If you can read this... 01110101 01110010 00100000 01100001 00100000 01100111 01100101 01100101 01101011
To see the remains of ancient smokestacks which should lead to an answer to the Fermi paradox.
well the radiation from the granite kills off bacteria, right? I think that's a win win.
Nowhere near "plenty" as far as the job of converting all that CO2 into organic molecules is concerned, unfortunately. Have a look at http://en.wikipedia.org/wiki/File:AtmosphereofVenus.png - the only hydrogen-bearing compound abundant enough to even make it on the chart is water vapor, at twenty parts per million.
Assuming life was able to start there in the first place (and given large amounts of water and the right temperature, it seems possible it could had). Organisms that thrived on excess CO2 and helped trapped excess CO2 should have flourished and helped regulate the atmosphere.
When I see the title, before even looking at the tags, I know what they will be. I'm not sure if that is /. polluting my mind, or if polluted minds are intrinsically drawn to /.
if you actually converted venus's atmosphere to something approximating earth's, it wouldn't be as hot anymore. right now, venus is the same temp, pole to equator, night to day. but reduced, the atmosphere would be like living in the desert, you'd have very cold nights, and very hot days. and since a day on venus is 100 days long, it means you'd have a siesta culture where everyone stays inside midday, and inside midnight. dawn and dusk would be pleasant in between, and dawn and dusk would last weeks. ecologically, you'd grow your crops like they do in northern climes on earth, except that winter/ summer would actually be night/ day seasons
as for your unstable balance of o2 and carbon, thats pretty much earth, right now. i can walk into most any nonwater environment on earth and start an inferno by myself if i wanted to. and yet our biosphere has lasted a plenty long time, mainly because the biosphere maintains the balance. it would be maintained biologically the same way on venus
however, you do allude to low amounts of hydrogen, which is an issue. and you don't mention the lack of geomagnetism, another serious constraint (constant bombardment of deadly high energy rays: so you stay indoors)
but those constraints in my mind are certainly no worse than the constraints of low atmosphere, low gravity, and low temperature (mars)
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
If this is true, Venus is now the number one planet to study. If it started out to be that much more Earthlike than we had previouly figured out to be than we need to know what happened to turn a potential Twin Earth to Hell. And is Earth going towards the same route and how much may Humanity have to say about it one way or the other? Why is it's rotation so slow? (Little known factiod, the extra weird thing about Venus' rotation is that it is locked to Earth in that whenever it is at closest approach to our world, it is always showing the same side)
This isn't +5 Interesting, it's a joke from the Simpsons.
Further down, if you would like to look, but I meant to say part of its atmosphere, which include the lighter elements of Oxygen, Helium, and Hydrogen. This left the denser elements which it consists of now(Nitrogen and Carbon dioxide.)
Just because you are wrong and I called you out on it doesn't mean I am a Troll.
Simpsons IS +5 Interesting
It's ok, I coated my granite counter top with lead to block the radiation.
NASA pap shows dent at Uranus' volatile (p)as(s)t.... this could be a cosmogasmic/galactigasmic pit sto(m)p...
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
A human would likely live "on Venus" in a floating city high up in its atmosphere.
Very nice description. However, Earth's plate tectonics can affect the rate of recession of the Moon. The configuration of the continents controls the size of the ocean basins, which in turn controls how dissipative the Earth is. The dissipation rate controls how quickly angular momentum is transferred from the Earth's rotation to the Moon's mean motion. As the moon gets more angular momentum, it moves away from the Earth.
That said, I agree with your post. I just thought this was a neat, if only tangentially related tidbit.
Chances are, it's still present on the planet, all up in the clouds, mixed with sulfur from volcanic activity, and has resulted in a much thicker atmosphere.
I'm probably wrong but an earth-sized planet (it's smaller by a small margin) losing all its water and earth not losing it at all through space (water isnt that lightweight) leads me to believe all of venus' water that isnt trapped in minerals in the mantle (oxygen and hydrogen rich minerals) is more than likely in the atmosphere and unable to fall back to the surface due to the extreme heat at the surface.
Good chance that the reason for this may also be due to why Venus is rotating backwards, It may have experienced an event that we fear happening here. A very large asteroid that was headed for the sun may have hit Venus over 500MYA and causes a resurfacing event, and the heat from the blast vaporized all the water on the planet, and large amounts of sulfur from the resurfacing event mixed with the clouds.
Who knows, Venus may be in the middle of being "reborn" for all we know. Similar to the event that's theorized to have formed the moon in regards to earth. Something huge hit Earth, and the planet was resurfaced.
Hell, it could have been a moon in Orbit around venus that collided for all we know, something HUGE had to have collided with Venus at some point to cause the rotation to not only slow down to 243 Earth days, but to go in reverse.
I've never heard that one before. I know that tidal forces are slowing down the Earth-Moon system's rotation and are causing the Moon to drift farther from the Earth. But, it makes sense that the distribution of ocean water would impart some variability to the equation. I wonder if the Tharsis Bulge on Mars has similar effects . . .
You know, I always tell my students (I'm an earth science professor at a community college in NYC) that Plate Tectonics explains everything on Earth. This is another great example. I'll have to figure out how to work it into one of my lectures. It'll make their ears bleed just a little bit more than usual >)
You're thinking of a Lagrange point. It's analagous to a geostationary orbit -- it's position is fixed in space relative to two large masses.
I really people would learn the rules of the English language - they're not that difficult.
i said it would EASIER than terraforming mars
with mars, you're faced with the problem of making an atmosphere where there isn't any. that seems like a harder problem than getting a high oxygen atmosphere to behave. you talk about bombarding venus with alkali metals or calling up lando calrissian: these seems way harder to me
" Photosynthetic life might help maintain a livable environment after you've made it livable, but it's not going to get there by itself - no way no how"
absolutely opposite that statement: if we are ever going to make venus livable, photosynthetic life is pretty much probably going to be the only route that is arrived at. if we are ever going to terraform venus, we are going to genetically engineer some pretty amazing critters (again: EASIER than mars, not EASY). with all that sunlight, all that energy, enough of those critters can be on full time biochemical effort keeping that oxygen in check. as a case study, i offer you earth: the same problem, on a smaller scale
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
It *is* being done here on Earth -- see photosynthesis. You just need a broader definition of "we".
But, I wanted socialized health insurance!
I have always thought that if Venus had formed in Mars orbit, we would likely have a true second Earth in our solar system. It would have been able to retain surface water. It would have a significant atmosphere. What its atmosphere would be like, I don't have the expertise to hypothesize, but it would have evolved far differently than the current Venusian atmosphere.
The highest temperature ever recorded on Mars is 70F / 21C. With an atmosphere and the greenhouse effect, a Venus in Mars orbit would be significantly warmer with less fluctuation and more stability.
It would truly have been a planet worth sending a manned mission to.
But why lament something that never existed?
This ad space for rent.
Venus is actually quite terra-formable. It does have an atmosphere, an extremely thick one at that, which has caused its high temperature. It also has gravity closer to ours than the moon or Mars. If we could turn the CO2 into O2 and usable carbon (like for soil), we could eventually live on it. Wouldn't be easy, but probably more feasible than terra-forming Mars.
Hah! Venus is not even close to being as easy to terraform Mars.
Step 1. Cool down the planet. I suppose this could be done by placing a single huge or many smaller solar shades at the SOL-Venus L1.
Step 2. As the planet cools, the CO2 in the atmosphere will begin to freeze and fall to the surface. That dry ice needs to be sequestered into a more stable form, like calcium carbonite or maybe even diamond..
Step 3: Venus has a day that lasts 243 Earth days. The only way to speed up this rotation is to smack it with hundreds or thousands of big chunks of rock and ice (more on ice in a minute).
Step 4: Venus is a very very dry planet. Mars is dry too, but for different reasons. The water on Mars is frozen. The water on Venus is gone, baked out of the planet, cracked with UV and had it's hydrogen blow into space. That means that you can't even easily make water on Venus because it doesn't have much hydrogen available. The good thing is, while you're doing step three you can be adding water back to the system in the form of comets and water-ice rich asteroids.
OK, so now you have a colder planet with more water-ice than you started with and a day that isn't almost a year long. At this point, you're about even with Mars.
So what is the value of another Earth-size planet in the terms of real estate, land development, resources, etc?
And what do we do with the excess atmosphere from Venus? We ship it off to Mars, of course.
I recall reading that high up in the atmosphere the temperature wasn't so bad.
Once we have the technology to build floating cities, we'll be able to colonize venus without any terraforming.
And we'll probably have that technology before we get to Venus. See:
http://www.youtube.com/watch?v=5oNHD41MLMk
http://hardware.slashdot.org/story/09/07/12/1612230/Robotic-Glider-Set-To-Break-Autonomous-Flight-Records?art_pos=1
The day length (one sunrise to the next) on Venus is 116.75 Earth days. Interestingly it takes 243 Earth days to rotate a full 360. That's more than a Venusian year (224.7 days)!
Anyway, that long a day would be tough to adapt to. You'd essential have a year in 117 days with very hot summers and very cold winters. But I had a thought that you put a very large mirror in a 24 hour orbit around Venus so as it passes in front of the Sun it provides a simulated night on the sunlit side (I did say very large) and as it passes around to the dark side the elements of the mirror are tilted to provide a simulated day. It might work.
Except that the atmospheric pressure it 90 time that of earth.
Lets compare scientifically. We cannot use the actual temperature of Venus since this is dominated by the greenhouse effect of the atmosphere so lets use radiation. The mean distance of Venus to the sun is 108M km vs. 146M km for Earth so Venus will receive 1.83 times the radiation from the sun (1/r^2). We can assume that it radiates the sun's energy at the same rate (i.e. assume equilibrium) so using Stefan's law we see that the radiation rate is proportional to T^4 (where T is in Kelvin). Hence if Venus radiates at 1.83 times the energy of the Earth then (T_venus/T_Earth)^4=1.83 assuming that Venus and the Earth are identical bodies (which if Venus were terraformed is not a terrible assumption). Solving this we get that:
...but remember this is in Kelvin NOT centigrade. The mean temperature of Earth is 14.6C=287.6K so the mean temp of a terraformed Venus would be 334.5K or 61.5C.
T_venus = 1.163*T_earth
The mean high temperature in Phoenix is 41C in the height of summer. The AVERAGE temperature on Venus would be significantly higher than this. Indeed the temperature at which skin burns is ~55C hence you will literally burn given the mean Vesuvian temperature - going inside will not help! However Venus is slightly smaller than the Earth so the temp will actually be higher and even assuming variations it is unlikely that there will be any inhabitable parts of the surface without extreme air conditioning. Indeed liquid oceans may be a problem since if the mean temp is 61C there are very likely to be places above 100C which will increase humidity and then temperatures further.
It is also worth pointing out that cooling is a LOT harder than heating. To survive on Venus you would need air conditioned suits compared to just thick insulation for Mars. In addition to get even this far you have to remove the bulk of Venus' atmosphere. If you think adding an atmosphere to Mars would require "magic" then removing Venus' atmosphere requires this and more.
Compare Mars to the south pole (or even Edmonton, Alberta where the temperature in winter is below that on Mars in the summer - I remember coming in to work one day when it was -35C to find the NASA rovers were reporting a balmy -22C on Mars!) and, except for the atmosphere, there is not a huge amount of difference. Yes it would be colder than Earth but colder is easier to deal with - indeed we already know that there are organisms on Earth that can survive (but not prosper) on Mars as it is today which is why any craft that travel there have to be sterilized to avoid contamination of Mars.