Venus / Mars

dickbill · 2003-02-17 10:30:43

In any event, we just have to go about our business on the assumption that things will remain much as they are now. If we were to base all our planning on the assumption that a major disaster could befall us any minute, I guess we'd just huddle together in the basement, hold hands, and wait for armageddon!
In other words, I think we have to be optimistic and hope for the best.

Sure, but the thread was about terraforming Venus versus Mars.
Mars seems just to wait for it while Venus is a hell of a planet to terraform, impossible in my opinion.

About the sun stability, I am not convinced that small scale changes are impossible in our human span life. I am not talking about end of the world here, just significant climatic impact. The "small Ice Age" during middle age for example, might have been cause by such a small solar fluctuation. What would happen with the reverse, I mean a small increase of solar imput on top of the already globally warming earth: Certainly a big ecological impact but not the end of the world.
Just better for Mars.

Shaun Barrett · 2003-02-17 20:10:24

All true!
I agree with you.

Palomar · 2003-02-17 20:17:37

Venus is a hell of a planet to terraform, impossible in my opinion.

*Um, yeah. My thoughts exactly. If I recall correctly, lead would melt on Venus and the atmospheric pressure is enough to pulverize just about anything. I once heard that light rays are so weirdly bent on Venus that if one were able to be there, looking around, one could see the back of one's head on the horizon. I don't know if that theory is valid or not, but I'm sorry to say I think any talk of terraforming Venus is essentially pointless...at least until greater/MUCH more advanced technologies become available. Arthur C. Clarke included a tiny colony (manned by just a few people) on Venus in one of his 2001 sequels; I wonder if that was an attempt to sensationalize a bit or if he does foresee it as possible in the future at some point. ::shrugs::

I don't mean to be a "party pooper," because I'm all for colonization, exploration, etc., anywhere we can manage it...but I think Venus is probably "a REAL stretch" as these matters go. But hey -- if we ever manage it, that'd be wonderful.

--Cindy

RobertDyck · 2003-02-18 11:14:51

Ok, so I am one of the pro-Venus guys. I strongly disagree with Martyn Fogg's criticism of Carl Sagan's work. Carl Sagan's idea is basically sound; the details are just a lot more complicated. Carl Sagan is the one who proposed seeding the atmosphere with bacteria to convert CO2 into oxygen and carbon. At that time scientists thought the surface pressure of Venus was 6 times Earth, now we know it is 90 times Earth. Yes, the surface condition of Venus is hellish right now: 92 bars pressure (Earth is 1.01325 bar), temperature is around 850?C depending on latitude and altitude, and the clouds have mild sulphuric acid. There is no sulphuric acid in the atmosphere close to the surface, but the lowest 30 miles have carbonyl sulphide, which is a stronger corrosive.

Terraforming Venus involves some interesting genetic engineering. The clouds of Venus have about 1 atmosphere pressure and temperature that hovers around freezing: warm on the underside and cold on top. This is the same as clouds on Earth. However, at the extreme altitude of Venus clouds there is very little dust, so little trace elements to support bacterial life. Chlorophyll requires 1 atom of magnesium per molecule. However, halobacteria use retinal as its pigment instead of chlorophyll, and retinal consists of just hydrogen, oxygen, carbon, and nitrogen. Other enzymes can be engineered to avoid missing elements in the clouds of Venus.

Photosynthesis of archaea is not as neat a closed system as the double-photosystem used by eukaryotic cells; it has waste products. Photosynthesis for Venus could be engineered to consume CO2 and excrete a solid that will remain stable in Venus current conditions, and would not be toxic in soil after terraforming. I tried coming up with such a substance myself: C3O6 as a ring alternating between carbon and oxygen would be quite unique and probably unstable. My chemist friend suggested a polymer (plastic). Chemically engineering such a waste product to sequester atmospheric carbon and oxygen would be an interesting inorganic chemistry problem. Designing a process by which an organelle could produce it would be an interesting biochemistry problem. Genetically engineering a bacterium to grow such an organelle is possible with today's technology, but would demonstrate complete mastery of genetics.

Terraforming would involve these initial exotic engineered archaea bacteria, but they would be designed to be poisoned by oxygen. When rain starts to fall on mountain tops and pressure reduced sufficiently, cyanobacteria can be introduced to produce oxygen. That is followed by the whole colonization of life.

For those who want to strongly advocate Mars; don't worry, biological terraforming of Venus would take a century or so before humans could walk on the surface. Mars can be colonized now and terraformed later. Venus has the advantage that it has 89% surface gravity vs Mars 38%, 90.0% the surface area vs Mars 28.37%, and Venus has no shortage of atmosphere. But it may require a few comets directed into it to deliver more water, and an artificial magnetosphere to retain its water. Length of day would be just a unique feature of Venus, but maintaining a stable temperature could be a challenge. I would like to see genetic engineering work now for microbes to terraform Venus, and advanced climatology and planetology to design the ecosystem. Once we are ready, we could seed the clouds of Venus and wait while colonizing Mars. Such terraforming work could be applied to Earth to control the weather and provide stable food production.

tim_perdue · 2003-02-18 20:26:51

A little injection of reality. What's the point of terraforming Venus or any other hostile planet?

For a tiny fraction of the cost and effort you could build large habs under the ocean or huge caves here on earth.

Completely sealed caves or ocean dwellings give you the "redundancy" that some people see in terraforming, at a minute fraction of the cost. Plus it's easy to get supplies and such in an emergency.

How about buying an old mine or something and "terraforming" that? It's doable with today's technology.

soph · 2003-02-18 22:11:25

But none of these offers the science value, surface area, or materials that Mars can offer. Or the technological motivation.

noctis · 2003-02-19 11:02:45

i really don't think that's the point in reality for any of this
i can't explain why i feel the way i do about mars..., it seems specific though, i don't get the same thing about venus at all
a mixture of the places, names, landscapes...
if the new rover mission actually suceeds, those photos will be amazing, better than anything we've seen, i'm sure thaqt will turn some people around to our way of thinking

noctis · 2003-02-19 11:04:42

especially the barcham dunes in vastitas borealis....
wonderful, and something we would definitely lose in terraforming

soph · 2003-02-19 14:47:59

Ah, but what if we gain beauty by adding water, and greenery to all these places?

noctis · 2003-02-19 17:35:30

if you add water there, the whole thing turns into an ocean, pretty homogeneous!... i don't know either way really

soph · 2003-02-19 17:43:05

sure, but then you can see Olympus Mons with snow-caps, Valles Marineris with rivers flowing through it, lush greenery...you would replace the vistas now with equally stunning vistas!

noctis · 2003-02-19 18:04:13

but i don't want an earthlike mars...
i think araeoformation to create a unique ecosystem is good
not so sure about turning it into a new earth...
(i.e. limited, with hardy plants, maybe a few animals, no seas, you'd never get snow on the tharsis volcanos anyway, they're too far above most of the atmosphere, i think)

tim_perdue · 2003-02-20 09:48:37

But none of these offers the science value, surface area, or materials that Mars can offer. Or the technological motivation.

I think Mars exploration is cool, I'm just being the devil's advocate.

The issue of minerals, surface area, etc are easily achieved underground here on earth at a fraction of the cost and without the debilitating low-gravity effects.

dickbill · 2003-03-20 14:20:01

Hi all,
In the red colony.com, Lichens are presented as tough living organisms possibly useful for Mars terraformation.
Searching a little bit in Pubmed (I copied part of the abstracts and emphazise some interesting passages) I saw that symbiotic cyanobacteria can also associate with other organisms than fungus, as mention this paper:

?Ann Microbiol (Paris) 1983 Jul-Aug;134B(1):205-28
Cyanobacteria-eukaryotic plant symbioses.
Stewart WD, Rowell P, Rai AN.
N2-fixing heterocystous cyanobacteria develop in symbiotic association with a small number of eukaryotic plant species belonging to the algae, fungi, liverworts, ferns, gymnosperms and angiosperm... ?

Then, this paper argues that the lichen symbiosis model, the lichenization, aroze infrequently in the past, but can be lost thereafter:

?Nature 2001 Jun 21;411(6840):937-40
Major fungal lineages are derived from lichen symbiotic ancestors.
Lutzoni F, Pagel M, Reeb V.
Department of Botany, The Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, Illinois 60605, USA. lutzoni@fmnh.org
About one-fifth of all known extant fungal species form obligate symbiotic associations with green algae, cyanobacteria or with both photobionts. These symbioses, known as lichens, are one way for fungi to meet their requirement for carbohydrates. Lichens are widely believed to have arisen independently on several occasions... Our results show that lichens evolved earlier than believed, and that gains of lichenization have been infrequent during Ascomycota evolution, but have been followed by multiple independent losses of the lichen symbiosis. As
a consequence, major Ascomycota lineages of exclusively non lichen-forming species are derived from lichen-forming ancestors...?

Actually, Lichenization still happens, as mention in:

?Mol Biol Evol 2002 Aug;19(8):1209-17
Genetic diversity of algal and fungal partners in four species of Umbilicaria (Lichenized Ascomycetes) along a transect of the Antarctic peninsula.
Romeike J, Friedl T, Helms G, Ott S.
Botanisches Institut, Heinrich-Heine-Universitat, Universitatsstr. 1, Dusseldorf, Germany.
Lichens from the genus Umbilicaria were collected across a 5,000-km transect through Antarctica and investigated for DNA sequence polymorphism in a region of 480-660 bp of the nuclear internal transcribed spacer region of ribosomal DNA. Sequences from both fungal (16 ascomycetes) and photosynthetic partners (22 chlorophytes from the genus Trebouxia) were determined and compared with homologs from lichens inhabiting more temperate, continental climates. The phylogenetic analyses reveal that Antarctic lichens have colonized their current habitats both through multiple independent colonization events from temperate embarkation zones and through recent long-range dispersal in the Antarctic of successful preexisting colonizers. Furthermore, the results suggest that relichenization-de novo establishment of the fungus-photosynthesizer symbiosis from nonlichenized algal and fungal cells-has occurred during the process of Antarctic lichen dispersal. Independent dispersal of algal and fungal cultures therefore can lead to a successful establishment of the lichen symbiosis even under harsh Antarctic conditions.?

So, here we are, almost on Mars. Lichenization can occurs pretty easily in the tough Antartica environnment. I also read about attempts to artificially create lichen symbionts. I just wonder if a lichen symbiont including the Radiococcus Radiodurans bacteria would be of any interest
for Mars terraformation. Radiodurans is very resistant to DNA breakage through radiations or intense dessication, basically impossible to kill. Radiodurans on Mars wouldn?t die but it wouldn?t grow either. It would just stay frozen forever (maybe future biologists will be interested to test the russian probes which crashed on Mars for radiodurans survivors). Frozen forever, or until it find a less hostile environment, like a lichen endosymbiotic ecosystem. In exchange for the lichen ecosystem, radiodurans would have to excrete its DNA repair enzymes to repair it?s host broken DNA (broken by the martian UV or radiations) .
Symbiosis is the key. For example, there is almost no atmosphere on Mars, but symbiotic micro ecosystem could create a transparent shell of protein , or dead cells, like a transparent chitinous bulb, from inside that micro-dome, temperature and pressure would allow liquid water to exist. A whole ecosystem could florish inside this enclosed ecosystem, and DNA breakage would be processed by D. Radiodurans. Gaz or material exchange couldn?t be passive through porous material, as the whole ecosystem would evaporate or sublimate quickly, but though a vacuolisation like a living micro-airlock system.
Possibilities are endless.

dicktice · 2003-03-21 09:33:31

Call me simple minded (nothing new) but: Mars, no matter what you do, everything will turn out uniquely different merely because of the 1/3rd-gee. Structures tall and thin with breath-taking spans, waterfalls like gauze, waves unreal in height, monorail maglev surface as well as catapult launched sub-orbital transport, human powered ornothopter flight.... Nothing at all like Earth!

Palomar · 2003-03-21 10:00:40

Call me simple minded (nothing new) but: Mars, no matter what you do, everything will turn out uniquely different merely because of the 1/3rd-gee. Structures tall and thin with breath-taking spans, waterfalls like gauze, waves unreal in height...{snip}

*Waterfalls like gauze...

WOW; the mind's eye reels. What are we waiting for?

--Cindy

Shaun Barrett · 2003-03-21 19:03:04

I just love all this conjecture about how things would look and behave on a terraformed Mars!!

Being an Aussie, I love surf beaches (something which bugs me at the moment because we currently live in the 'shelter' of the Great Barrier Reef - no surf!! ), so my mind keeps coming back to the shores of Oceanus Borealis.
I try my hardest to imagine walking on the sand as a brisk cool north wind brings in the breakers from the Utopia Sea. But the waves, though taller, fall slower and softer and with less of a 'crash' than they do on Earth. And the sound is gentler and more muted in the attenuated air. And then there's the beautiful Martian sunlight - bright and clear, but without the harsh glare of Earthly sunshine - like wearing medium-tint sunglasses without having to wear sunglasses!

Cindy:-

What are we waiting for?

You said it, sister!!! I'm ready to go!

New Mars Forums

Announcement

#26 2003-02-17 10:30:43

Re: Venus / Mars

#27 2003-02-17 20:10:24

Re: Venus / Mars

#28 2003-02-17 20:17:37

Re: Venus / Mars

#29 2003-02-18 11:14:51

Re: Venus / Mars

#30 2003-02-18 20:26:51

Re: Venus / Mars

#31 2003-02-18 22:11:25

Re: Venus / Mars

#32 2003-02-19 11:02:45

Re: Venus / Mars

#33 2003-02-19 11:04:42

Re: Venus / Mars

#34 2003-02-19 14:47:59

Re: Venus / Mars

#35 2003-02-19 17:35:30

Re: Venus / Mars

#36 2003-02-19 17:43:05

Re: Venus / Mars

#37 2003-02-19 18:04:13

Re: Venus / Mars

#38 2003-02-20 09:48:37

Re: Venus / Mars

#39 2003-03-20 14:20:01

Re: Venus / Mars

#40 2003-03-21 09:33:31

Re: Venus / Mars

#41 2003-03-21 10:00:40

Re: Venus / Mars

#42 2003-03-21 19:03:04

Re: Venus / Mars

Board footer