Terraforming Venus

[granthutchison]

Anyone fancy terraforming Venus?
Here's a sun-synchronous Venus parasol, which blocks just enough of the solar disc to drop the level of illumination to Earth normal.
These things are so big they're affected by radiation pressure, so can't sit precisely at the stable L1 libration point between the Sun and Venus - it needs to be a little sunwards of that point. How far sunwards depends on the density per unit of area of the material the parasol is constructed from - the lighter it is, the further sunwards it sits at equilibrium. But the further sunwards it goes, the bigger it has to be to provide the same amount of shielding. So I've chosen the minimum-mass configuration.
This is still close enough to Venus to give a slight awkwardness from the variation in line of sight across the Venusian disc - at Venusian sunrise, you'll see the parasol dangling slightly off one side of the solar disc; by midday it's centred on the disc; and by sunset it's dangling off the other edge. This will allow just a tad more insolation at sunrise and sunset, but the mass penalty of moving the parasol farther from Venus to prevent this effect is huge.

Code: Select all

"VenusParasol" "Sol"
{
   #Mesh "empty.3ds"
   Color [ 0 0 0 ] 
   Radius 6000     

   CustomOrbit "vsop87-venus"

   Obliquity              3.3947
   EquatorAscendingNode  76.681
      
   Albedo 1.0
}

"Parasol" "Sol/VenusParasol"
{
   Radius 7040         
   Oblateness 0.99999

   EllipticalOrbit {                         
      Period            224.701
      SemiMajorAxis     1586000
      Eccentricity      0.0068      
      LongOfPericenter 234.852
      MeanLongitude    285.298
   }                         

   Obliquity               90
   EquatorAscendingNode    193.319
   PrecessionRate          1.602129051

   Albedo 1.0
}


Grant

[JackHiggins]

Kill 2 birds with one stone- if only there was some way to take some of venus' atmosphere, & bring it to mars...

Sun holidays on venus & skiing on mars...?

[Assinio]

People think that slamming a few comets into the crust of Venus at a bias will get the place up to a decent spin in no time. Alas, when you look at craters, you notice they tend to be round. Most of the force of an impact goes straight up from the center of mass. Even so, you're more likely to nudge a tectonic plate (if any) instead of getting the whole planet in on the exchange of angular momentum.

What Vens nees is a moon - a damn big one, and close enough to make a twin tidally locked body. Titan would do peachy, but Callisto could do in a pinch. Lots of water to ship down, and after a bit of slimming should still have enough bulk to serve as a tidal anchor. Then again, we're aleways forgetting the nitrogen, so we might do better with Titan or Triton.

Still, Venus is, and has been for a long time - hot. Getting the core temperature of Venus down to a reasonable level, not to mention getting rid of all that sulfuric acid and excess COs, might be easier donw erecting a big enough shield to sllw Venus to literally sit in the dark, radiating away the hear of the body for a few centuries, until the athmosphere can be scraped off as ice.

Then again, if greenhouse worlds are so predominant in our estimates of extrasolar planets, we might have the awkward problem that somethiong HAS adapted to them, and that the visitors from Out Yonder drop by, and find it a charming place to stay, unlike those frosty, NitrOx bogs.

[Guest]

People think that slamming a few comets into the crust of Venus at a bias will get the place up to a decent spin in no time.

Much easier (we're talking "easy" in relative terms, here ) to blot out the sun entirely with a larger version of my parasol, as you say, and then place a soletta in a polar orbit, reflecting sunlight in from beyond the parasol's shadow cone. The sun track is interesting - from one pole, across the equator to the other pole, then back up the far side of the planet, as Venus rotates slowly beneath. So the poles are "tropical" because they see they see the sun every day, whereas the rest of the planet alternates "tropical" with "polar" twice a Venusian rotation period.
I made a model of this, too, but it's entirely unconvincing because Celestia doesn't let me model the illumination from the polar soletta.

Grant

[granthutchison]

Oops, that was me, not logged on.

Grant

[Don. Edwards]

Hey everboby,
Here is a nice picture of a Terraformed Venus I did a while back.



Just thought I would drop this into the coversation.