Nocturnal species in Venus’s terraformed equatorial forests

Should our descendants make Venus’s equatorial super hot forests fluorescent, or give the animals which live there echo location? The answer might be a bit of both. Because Venus is unlikely to have a moon in the first centuries after terraforming, helping creatures find their ways around the equatorial continents in the relative cool of the night will be very important.

The decision of using bioluminescence or of equipping the animals with echo location will probably come down to the ways in which echo location would transform the appearance of the animal. For example fruit bats might benefit from echo location as they would have to avoid bumping into each other as well as trees, mountains and cave walls. And their appearance might not change too much if the were given echo location. On the other hand a predator like a jaguar might prefer not to be luminous, but for his prey to be easy to see. Additionally jaguars might look a bit odd with large echo locating ears. The prey on the other hand might not want to be seen either, but would want to see the jaguar.

So it is a simple choice between making all the plants, hills and caves luminous or giving all the animals large ears. Purists will probably prefer that all the plants and fungi have their DNA altered so that they can be seen in the dark, and that all animals remain invisible at night to all others apart from those which travel in large groups and need to avoid collisions. Those who see the echo location route as the simplest need not make anything luminous, but will need to alter the ears, faces and brains of each and every animal which needs to be active at night – which will probably be the majority.

 

Seeding Venus’s terraformed equator

With high temperatures and a blistering sun, the introduction of the first life to Venus’s equator will be difficult. The spots used for the seeding of the most basic forms of life – microorganisms – will need to be places like the narrow north-south clefts between rocks where nutrients and water exist and there is plenty of shade. Places like this on Earth can be shallow as in a limestone Karst landscape or very deep as in some desert oases. Key nutrients may need to be artificially supplied, but choosing a place where both water and nutrients exist naturally would help life to spread beyond the narrow confines of the cleft.

This gradual addition of life, from the microorganisms up toward more advanced plants and animals would help to create a shaded ecosystem where only mature trees would receive the sun’s full intensity and everything else benefits from the shade. The trees would also support the rest of the ecosystem by the production of edible flowers, fruit, leaves and bark.

To help the trees spread beyond the original narrow cleft would require seed dispersal by species which can move outside their ecosystem. Nocturnal fruit bats could do this, but would need more protection from the sun’s heat than just a daytime roost in the branches of  semi-mature trees. This may mean artificial shelters need constructing or lava tubes locating so that they can survive daytime temperatures.

Additionally nocturnal fruit bats on earth only fly on moonlit nights, which with no Venusian moon would mean they would need another way to find their way about in the dark. This might mean everything in these forests would need to be luminous, or that fruit bats would need to borrow echo location from their insectivorous cousins.

Figs and the Planet Venus

Heat tolerant trees which can colonise bare lava will be critical to establishing life on Venus and figs are almost certainly the best of these. They have fruit which helps to feed hundreds if not thousands of animal species on Earth and would most probably do the same on a terraformed Venus. They also have the advantage of small seeds which are spread in the droppings of mammals and birds in many cases long distances from the parent tree. They are fertilised by a species-specific fig wasp which will also fly long distances to find new figs to fertilise.

There are problems however due to the very high temperatures which might exist on terraformed equatorial continents on Venus. On Earth both trees and wasps are comfortable at temperatures below 35 degrees Celsius. On Venus the temperatures at the equator might rise as high as 60 degrees, meaning that both figs and wasps would perish without changes to their makeup.

This would most likely mean replacing some proteins, enzymes and other biochemical agents with extremophile forms which could function at higher temperatures. The genes for these chemicals would also need changing so that the species could produce viable seeds and feed the animals reliant on them.

Venus’s continents and terraforming

The planet Venus already appears to have continents, Ishtar in the north and Aphrodite on the equator. They may be a remnant of a time when Venus had plate tectonics like on Earth, which means that the crustal plates were able to slip over the mantle and to collide with each other or be sub-ducted under each other to create mountain chains. However this process needs water, plentiful on earth, but almost non-existent on Venus. It may be that billions of years ago Earth, Mars and Venus all had water and the conditions necessary for life. But Mars went into deep freeze and Venus became a roasting hell.

When the day comes for our descendants to transform Venus from its present hyper-hostile state into a planet where life can prosper; a number of steps have to be undertaken to make this possible. The first is the removal or transformation of the atmosphere. That’s the most difficult step, and trying to envisage how that might be done is like someone in the tenth century imagining how people today would get from York to Jerusalem in three hours.

However let’s try anyway, and imagine that physicists in a thousand years understand a good deal more about space, relativity and particle physics than we do today. Already they are starting to say that even a vacuum has structure, and that three quarters of the particles which make up matter are missing. If this is correct, then they may have ways of bending space or even of creating holes through it into other regions of space or other dimensions. This then might allow Venus’s atmosphere to be removed to somewhere it wouldn’t cause any contamination problems for Mars or Earth.

The next steps would the correction of Venus’s spin, which at present gives Venus a day length equivalent to 225 earth days. This would also mean a night of 225 earth days, during which any plants added to Venus’s surface would die. Therefore correction of this slow rotation is essential if life is to exist on its surface. This would best be done using large asteroid strikes, delivered as twins with one on each side of the planet to speed up its rotation. Increasing the rotational momentum of an object as massive as a planet would take a terrific amount of energy and therefore that additional momentum would need to come from large chunks of rock sourced from the asteroid belt and accelerated to have sufficient energy to do the job. This would of course mean multiple twin asteroid strikes, as too few would either not increase rotational speed sufficiently or might cause the break up of the planet. Additionally these impacts, all on the equator, would produce new continents right around Venus’s circumference. This is because no single spot should be hit more than once as that could also cause planetary breakup. Once this step is complete, the surface may need to be left to cool before moving onto the final step.

Earth has seasons, Venus does not. This is due to the 23 degree tilt of the earth’s axis. Venus does have a very small 2 degree tilt, but this would need to be increased to be as close as possible to Earth’s. Here again twin asteroid impacts would need to take place to correct this. However this is a case in which the same places near Venus’s north and south poles would need to be struck repeatedly until the correct tilt had been achieved. The impacts would need to be small and regular to avoid punching holes through the crust into the mantle and initiating massive volcanism. However the outcome would be the creation of two new continents.

So with the string of three or more continents along the equator, two new continents near the north and south poles, plus the existing Aphrodite and Ishtar landmasses gives us an approximation of six continents on a future terraformed Venus.

Manufacturing with nano technology

On earth the smelting of metals is a difficulty and dangerous occupation needing high temperatures and limestone fluxes. On planets like Mars; energy will be limited and most fluxes unobtainable. Using bio leaching may be tried, but bacteria and other microorganisms may be too slow to manufacture the structures we need our survival.

Therefore our descendants will need to look at nano robotics for a solution to the concentration and assembly which on earth we do with smelting, casting and forging. The nano solution to this problem is likely to come after the nano mining revolution, but to use the same technology.

The idea is to make a single nano machine as an ultra thin two dimensional object and to give it the chemical ability to increase its own thickness by lying against materials of the right concentration. It would then split in two along its thickness to create two identical copies of the first machine.

The next step in the process would allow the nano machine to move to a new position and there to fuse with other nano robots to create a strong stable join. They might do this chemically, electrically, magnetically or physically with for example spines or claws. In this manner a structure like a beam or support could be constructed, without high temperatures or fluxes.

Mining with nano technology

How do you mine an asteroid if each impact of your spade sends you flying off into space? You could try sticking or tying yourself to it; which might be possible. If for example the asteroid was small enough you could throw a rope around it and use that to hang on tight. But if it’s small enough to be lassoed, why not just tow it to where you need it rather than trying to mine it.

If its too large to be lassoed, then you will have to find a way to hang on tight. You could secure a footing using claws, or you could melt and re-freeze pits around anchors. Probably the approach will vary with the composition of the asteroid, and standard operating procedures will have to be developed for each.

In the longer term there is another alternative and that is to use nano scale robotics. Although this technology is in its absolute infancy, micro scale robots have already been manufactured and have been able to perform a number of simple functions such as pumping liquids. To make nano machines useful for mining they would have to be able to separate, move and concentrate materials as diverse as metals, water ice and frozen gasses. To make them really useful they would need to be capable of replication, meaning that once a single nano robot had been planted on an asteroid, it would use the minerals in the asteroid to make identical versions of itself. If they were also capable of separating, moving and concentrating materials they would be able to extract resources with little human involvement other than design, planting and extraction.

 

The value of lava caves on Venus

Venus’s equator is likely to be hot despite everything our descendants do to shade the planet. It may be too hot for all but extremophile life forms. But that doesn’t mean they should not try to add life to Venus’s equatorial continents. However any life forms which are added will need to be preconditioned for heat by replacing some proteins, enzymes and other organic chemicals with equivalents which are more stable and better able to function in high temperatures on earth. This might mean taking the gene which expresses a particular protein from a heat tolerant algae, and moving it to a fig tree to perform the same function on Venus.

This is likely to be a complex process as many thousands of genes may need modifying before a plant, animal or fungus becomes ready for life in equatorial Venus.

However even with these modifications, other strategies to reduce heat exposure will be important; such as living underground. Fruit bats are likely to be the animals most at risk of overheating as they will be needed to fly over virgin lava and plant the seeds of figs and other trees in their droppings. Even if they are nocturnal, underground roosts will prevent them from being exposed to high daytime temperatures in tree roosts. They would also need guidance so that they could find their way into caves from bioluminescent bacteria growing on the cave walls.

This logic is less relevance to birds, which like most animals would seek the cooler temperatures of deep forests. If trees are able to grow taller and faster than in earth due to higher temperatures, plentiful water and nutrient supply and plenty of carbon dioxide; then the deep forests will indeed be protected from the intense heat.

Seeding life into Mars’ ocean

Plankton are rather like soil microorganisms in that many thousands of species form the bottom of the food chain on sea and on land. This may mean that by the time we are ready to seed life onto Mars’ surface (once it has been terraformed with atmosphere and oceans) we may find that there are just too many microorganisms to reanimate directly from DNA sequences in computer memories. Therefore given that Mars is a cold planet and most of the plankton and microorganisms we will be trying to introduce will be cold tolerant, it seems sensible to bring samples from earth in frozen form. For soils this would be a filtered first to get rid of the sand and gravel, and for plankton it would need to be filtered to increase the number of species collected.

Other issues which would need to be considered would be which types of microorganisms and plankton to introduce first. For plankton this would mean phytoplankton which could use sunlight, carbon dioxide, water and minerals in the water to create plant tissue.

However the survival rate of the organisms in these samples is likely to be low, so repeated sample additions may allow an ecosystem to develop layer by layer. So the first survivors would be able to survive in isolation using inorganic resources, and the last would be predators which would need a rich micro ecosystem to be in place for their survival.

Tides and Mars’ great northern ocean

With just two small moons (Phobos and Deimos) the tides in Mars’ terraformed northern ocean are likely to be small. In fact the tidal range may be somewhat like the Mediterranean’s at just a meter between low and high water. This does seem to be enough to keep the Mediterranean mixed and prevent water stratification, however the Mediterranean doesn’t have Mars’ low gravity and possibly lower atmospheric pressure.

Even if carbon dioxide and noble gasses can be used to make Mars’ atmospheric pressure similar to earth’s, the low gravity may produce effects we don’t see on earth like foaming and large area spraying.

These together may increase the oxygenation of Mars’ ocean, but make it too hostile for air breathing marine species like whales, dugongs and sea turtles. However fish should do very well on Mars.

The Venusian parasol

Even if our descendants find a way to remove or substantially alter Venus’s atmosphere, it will be a hot planet and very hot at the equator. Therefore to reduce equatorial temperatures some way will need to be found to block some of the sunlight. This could be done using some sort of umbrella sitting above the planet, however this approach is likely to be both very difficult and hugely expensive.

An alternative would be to introduce something into Venus’s upper atmosphere to do the same job. This could take one of two forms: floating plants which excrete a light gas into an internal float. However with oxygen being the main gas plants breath out these floating plants would sink in an oxygen – nitrogen atmosphere. The alternative would be small machines which capture and concentrate hydrogen or helium into a balloon float. These would float, but would need to be able to repair sun damage to the float itself.

The advantage of floating plants would be that if they could be made to float they would be self repairing and breed. The advantage of the machines would be that they could easily be upgraded.