New Results From Venus Express

Riding with Robots writes "For the past two years, Europe's Venus Express orbiter has been studying Earth's planetary neighbor up close. Today, mission scientists have released a new collection of findings and amazing images. They include evidence of lightning and other results that flesh out a portrait of a planet that is in many ways like ours, and in other ways hellishly different, such as surface temperatures over 400C and air pressure a hundred times that on Earth. The article lists seven papers that will be published today in Nature."

Comments

Fun debate in the car

[techpawn]

Heard this on NPR last night about how it may of had oceans at one time and they may have evaporated due to climate change (caused by solar flairs).

That sparked a debate between me and the other passengers about evolution via traveling to earth from Venus and the thought of doing the same to Mars...

Re:Can Venus be made habitable?

[kebes]

I would think the first step would be to boost the planet to an orbit further away from the sun. Changing the orbit of a planet is not really an option. The energy required to do is ridiculously large. Not to mention the difficulty of actually applying the required forces to a planet (without ruining it). Attach rockets? Launch asteroids into it (and bit by bit change its velocity)? In any case it would be very, very costly, and would require a long, long time.

But all that is unnecessary anyway, because Venus' orbit is not too far outside the habitable zone. One could, I suppose, eject a large percentage of the Venutian atmosphere in order to reduce atmospheric pressure, temperatures and greenhouse effects (via controlled explosions, perhaps?). To further reduce and control temperatures would require some geo-engineering. For instance, one could place a huge number of thin solar reflectors at the Lagrange point between the planet and the sun. These thin floating mirrors would reflect away some percentage of the sun's rays, thereby casting a "shadow" of sorts on the planet and reducing temperatures. This would of course be ambitious, requiring billions of lightweight reflectors to be placed into the proper orbit, but it's not unthinkable to do it. (Actually, some people are even suggesting it as a potential solution to control Earth's climate.)

After stabilizing the temperature there would still be many other things to deal with: the atmospheric makeup isn't very hospitable, and it would probably require millenia of active modification to bring it even close to being hospitable to simple forms of life (e.g. extremophiles). Presumably one would engineer these initial life forms so that they would convert the atmosphere as required (especially, to generate oxygen). So, it's probably possible in principle to make Venus habitable... but by no means easy.

Re:something is replacing the atmosphere

[SatanicPuppy]

It is a planet...That's a hell of a lot of atmosphere to strip.

Moreover as the ground temperature rises, you have more things transitioning to gas phase, and more gases means more atmosphere...Lot of the dense stuff will be more resistant to being stripped as well. Without knowing the amounts of various things that could have been stripped, as well as the pressure over time...If the planet had massive water oceans like earth, it could be that they stayed liquid for quite a long time if the atmospheric pressure were high enough.

Too many variables.

4 billion years from now

[Samus]

4 billion years from now the sun will have swallowed the earth and all the inner planets as it expands into a red giant. A slowing rotation will be the least of our worries. Still I've always thought that Venus would make a better planet for us to live on than Mars if we could change the rotation and overcome the rampant global warming. Its the only planet in the solar system that spins the other way. So whatever hit it early on did a lot bigger number on it than just creating a moon.

Hellish twin ...

[Ihlosi]

I always wondered why Doom takes place on Mars. Venus would be so much more appropriate.

Re:And in other news...

[MBGMorden]

While I do think global warming is serious issue that needs to be looked at, I don't think we have enough fossil fuels on the whole planet to burn that would screw Earth up to anything close to the situation on Venus. The one of the previous mass extinctions in Earth's history was attributed to severe volcanic eruptions that released about 6 times as much CO2 in the atmosphere as man has since the start of the Industrial Revolution.

Now, that to me is a scary and still hopeful message at the same time. One: six times as much doesn't seem like THAT much more. Considering that this resulted in well over 90% of all life on the planet dieing, that's not a pretty picture. BUT, on the other hand, if we haven't hit peak oil production yet, I'd guess we're getting close. When the oil runs out, we're gonna be forced into a much more green-fuel solution whether we like it or not. There are also other non-oil sources to deal with, but the rate of dumping will definitely be reduced. I wonder if we have enough crap to burn to screw us up THAT badly. Then again, there's still a giant array of terrible in-betweens that can happen between "perfect planet" and "mass extinction". We might not need to dump nearly that much into the atmosphere to wipe ourselves out.

Also, that disaster, while horrific (and probably one that HUMANS would not have survived), was not permanent. As severely fscked up as the planet got after all that gas was dumped into the atmosphere, life survived, and the planet eventually fixed itself. That does leave me hopeful in that even if we screw ourselves up, it'd be nice to still have life as a whole bounce back in a few million years.

DISCLAIMER: I am not a climatologist or any other type of scientist who speaks authoritatively. I'm just an avid Discovery Channel watcher who may have some facts wrong/outdated/misremembered. :)

Re:Can Venus be made habitable?

[sckeener]

I think we have time to make Venus habitable....we just need to colonize it first.
http://en.wikipedia.org/wiki/Colonization_of_Venus

Aerostat habitats and floating cities

Geoffrey A. Landis has summarized the perceived difficulties in colonizing Venus as being merely from the assumption that a colony would need to be based on the surface of a planet:

        "However, viewed in a different way, the problem with Venus is merely that the ground level is too far below the one atmosphere level. At cloud-top level, Venus is the paradise planet."

He has proposed aerostat habitats followed by floating cities, based on the concept that breathable air (21:79 Oxygen-Nitrogen mixture) is a lifting gas in the dense Venusian atmosphere, with over 60% of the lifting power that helium has on Earth.[4] In effect, a balloon full of human-breathable air would sustain itself and extra weight (such as a colony) in midair. At an altitude of 50 km above Venusian surface, the environment is the most Earthlike in the solar system - a pressure of approximately 1 bar and temperatures in the 0C-50C range. Because there is not a significant pressure difference between the inside and the outside of the breathable-air balloon, any rips or tears would cause gases to diffuse at normal atmospheric mixing rates, giving time to repair any such damages. In addition, humans would not require pressurized suits when outside, merely air to breathe and a protection from the acidic rain. Alternatively two-part domes could contain a lifting gas like hydrogen or helium (extractable from the atmosphere) to allow a higher mass density[5].

Cloud-top colonization also offers a way to avoid the issue of slow Venusian rotation. At the top of the clouds the wind speed on Venus reaches up to 95 m/s, circling the planet approximately every four Earth days in a phenomenon known as "super-rotation".[6] Colonies floating in this region could therefore have a much shorter day length by remaining untethered to the ground and moving with the atmosphere. While a space elevator extending to the surface of Venus is impractical due to the slow rotation, constructing a skyhook that extended into the upper atmosphere and rotated at the wind speed would be comparably difficult to constructing a space elevator on Earth.

Since such colonies would be viable in current Venusian conditions, this allows a dynamic approach to colonization in stead of requiring extensive terraforming measures in advance. The main challenge would be using a substance resistant to sulfuric acid to serve as the structure's outer layer; ceramics or metal sulfates could possibly serve in this role. (The sulfuric acid itself may prove to be the main motivation for creating the structure in the first place, as the acid has proven to be extremely useful for many different purposes.)

Landis has suggested that as more floating cities were built, they could form a solar shield around the planet, and could simultaneously be used to process the atmosphere into a more desirable form. If made from carbon nanotubes (recently fabricated into sheet form) or graphene (a sheet-like carbon allotrope), the major structural materials can be produced using carbon dioxide gathered in situ from the atmosphere. The recently synthesised amorphous carbonia might prove a useful structural material if it can be quenched to STP conditions, perhaps in a mixture with regular silica glass. According to Birch's analysis such colonies and materials would provide an immediate economic return from colonizing Venus, funding further terraforming efforts.

Re:And in other news...

[Xonstantine]

Humans, as we exist today, would probably survive a KT extinction level event. We are omnivorous, warm blooded, spread across the entire planet, adaptable to almost any environment, and capable of changing our environment on a micro scale in small numbers, and a macro scale in large numbers. And we have all sorts of structures above and below ground that were designed to withstand rather extreme events like nuclear explosions mere hundreds of meters away while keeping the inhabitants of the structures reasonably intact. While a large meteor or comet strike might kill 95% or more of humanity, enough people would survive to revive the SUV in short order.