Celestia Forums

I'd thought i'd post a transit of Earth been occulated by Runar Thorvaldsen's Blue Venus as seen from Mercury in 2133. As you can see Venus has darker water than earth but still looks brilliant. If it looks a little strange it's because i've tilted it to 25 degrees and i've set the rotation to 48 hours.
[img=http://img87.imageshack.us/img87/7920/bluevenusoccultsearthxv6.th.jpg]
I hope the picture shows and Runar doesn't mind me posting this.
I can post one with clouds if any want to request it.

Oooh, please do!

[img=http://img91.imageshack.us/img91/3280/bluevenusoccultsearthwithcloudsgh9.th.jpg]

There you go, same picture but with clouds.

Sorry to bump the thread like this but i've been tinkering with Celestia to give Blue Venus a moon (vital if it was ever Terraformed), called Dialuna (was supposed to be Dioluna, didn't realise until i looked on the thread where i got it from). The Pic was taken 300,000 KM from Venus' surface and 30,200 KM from Dialuna. Unfortunately it seems the texture's got screwed up which is why it is white.

[img=http://img177.imageshack.us/img177/5807/dialunaandvenuszd9.th.jpg]

Captain-insane wrote:to give Blue Venus a moon (vital if it was ever Terraformed),

May I ask why a moon is vital to terraforming?

I would imagine that if you wantyed a planet inhabitable on a geological scale, then a moon would be beneficial for various items, ranging from possibly driving tectonics to definitely keeping our axial tilt from swinging wildly.

On a civilization life time scale, though, having a moon is little more than eye candy. And, if a species is capable of placing a large enough moon in orbit of a planet to begin with, then likely they may not *need* to terraform planets....

...John...

Then again, Venus is closer to the Sun than Earth is, so solar tides are stronger there. Quick calculation suggests that solar tides on Venus are stronger than the lunar tides on Earth, so there shouldn't be any problems maintaining obliquity without a satellite. Incidentally this would also apply to habitable worlds around less luminous stars than our own - there may be an "optimum" range of luminosity where solar tides provide a stable obliquity but are not so strong as to tidally-lock a habitable planet.

The tectonics issue is another matter.

Interesting line of thought Dollan and Chaos, but I would more see the moons functionality here as a biological argument. Lunar phase appears to play some manner of essential role with nearly every living species on the planet (save humans - or so humans claim). It would make for an interesting experiment were we makers of real worlds.

I doubt that the dependence on lunar cycles are quite vital to life. If we populate a terraformed Venus (without a moon) with the species commonly found on Earth, if they are affected at all by the absense of a moon, they will adapt.

Just my thoughts.

Would you think such adaptation true of say... Corals?

Are corals actually necessary for a terraforming project to succeed though?

What exactly is the purpose of terraforming? To replicate the entire biosphere and all the different ecologies of Earth, or to provide human habitation?

If the latter, it is probably possible to get away with not adding certain environments. Given the sensitivity of corals to environmental factors, it seems highly unlikely they would succeed in most cases of terraforming. How much of a marine ecology you could set up without coral reefs, I don't know.

Plus, a civilisation advanced enough to run a gigantic project such as terraforming may well have several bioengineering tricks up its sleeve.

In any case, with Venus there are other more fundamental problems, even once you've dealt with the atmosphere, such as the long rotation period, lack of magnetic field, and lack of seasons.

I've not put much thought into the idea of terraforming Venus. Too harsh an environment to start off with - especially being we're beginners at this. I've always felt Mars would be the more likely candidate, even over our more nearby Moon.

Plus, a civilisation advanced enough to run a gigantic project such as terraforming may well have several bioengineering tricks up its sleeve.

Exactly!... and that civilization is 'us'. In 2001 I took a trip to Florida (USA) where I had the opportunity to visit the NASA facility. One of the presentations I made an effort to check out was the Mars Habitat project. It was an interesting presentation, and I even had opportunity to speak with one of the project associates. From my understanding, of the then current ideas and 'technologies' being considered for pre-settlement Mars terraformation - I'd say we're a lot closer to the capability of doing so than most would think. Our first terraforming 'machines' won't be machines at all - they'll be microbes.