Venus Rover

[ryan]

I found something on wikipedia on a possible Venus Rover that's being studied, it'll be cooled by a Stirling Engine cooler, http://en.wikipedia.org/wiki/Stirling_cooler
It's been studied at the Glenn Research Centre.
So i just wanted to know your guys opinions and or suggestions. For example the gains from this certain mission and such.

Thanks.
Ryan.

 

[Piper]

I found something on wikipedia on a possible Venus Rover that's being studied, it'll be cooled by a Stirling Engine cooler, http://en.wikipedia.org/wiki/Stirling_cooler
It's been studied at the Glenn Research Centre.
So i just wanted to know your guys opinions and or suggestions. For example the gains from this certain mission and such.

Thanks.
Ryan.

Hmmm, that's actually a really good idea I think. I'm curious to know how much energy (in watts) they believe can be generated by such an engine on Venus. However, you would still need an additional power source to cool down the "cold" end of the engine, but you could do that with a much smaller RTG then you would have needed to power the entire vehicle.

Of course, you still need to have the rest of the vehicle to be able to survive for an HTML clipboardappreciable length of time.

 

[RisingFury]

Cooling it simply by the use of sterling engine would be impossible. More heat will always make it in, then the work extracted from the heat exchange. I don't know the max efficiency of the system cos I don't have any data, but a maximum of around 30% of energy is usually extracted... and also, then cooling process is also not without it's losses...


You would definitely need another power source, but a better solution then an RTG would be solar cells that exploit the IR range. That's plenty on Venus, right?

Also... the material that converts heat into electricity that's used for RTGs... anyone have any info on it's efficiency, it's working (by surface, by volume?) or even it's name?

Perhaps simply that material and IR solar cells would be enough to power the vehicle and keep it cool.

 

[ijuin]

Does IR reach the surface directly in plentiful enough amounts, or is it mostly absorbed by the air?

If we can design a nuclear reactor that can operate at around 1,000K (i.e. at least 1/3 hotter than the surrounding air on the Venusian surface) while dumping its heat into the 730K air, then it can be used to power a refrigerator to keep the electronics cool. A fan to force air over the cooling surfaces would be good too.

 

[ryan]

I'm not a very science knowledgble person, so can someone give a small wrap up on what a rover would help to science on mars, and why should we even go there in the first place, it's not a sort of great holidaying spot.

 

[Linguofreak]

Hmmm, that's actually a really good idea I think. I'm curious to know how much energy (in watts) they believe can be generated by such an engine on Venus.

None. In this case, instead of evening out a heat differential across the engine to generate power, you're applying power to the engine to create a heat differential in order to keep the rover cool (hot end vents to the atmosphere, cold end keeps sensitive things from overheating). The stirling engine in question here is an air conditioner, not a generator.

 

[Urwumpe]

Still, you would need the "warm" end of the Stirling heat pump to be significant hotter than the Venus atmosphere, so you are emitting more heat radiation than you get from the atmosphere.

 

[tylor2000]

Take the third largest asteroid(mostly ovaline), crumble it up into fine powder and disolve it into venus' atmosphere. Then we can all go there for vacations.

---------- Post added at 02:31 AM ---------- Previous post was at 01:49 AM ----------

Wait, it might be another one. In any case I remember running across the problem and remember an asteroid with enough mass that was thought to be mostly ovaline and doing rough comparisons of the amount of carbon dioxide on venus and thinking it could be enough. I'm not a scientist or anything close to that(crank if anything) but it's still an idea.

 

[tblaxland]

What is ovaline?

 

[Urwumpe]

What is ovaline?

I think he means Olivine, a mineral.

http://en.wikipedia.org/wiki/Olivine

 

[cjp]

I'm not a very science knowledgble person, so can someone give a small wrap up on what a rover would help to science on mars, and why should we even go there in the first place, it's not a sort of great holidaying spot.

The rover here is designed to work on Venus, not on Mars. This is a new idea: so far, Mars is the only planet (besides Earth) where rovers have operated.

Mars and Venus are of scientific importance because they are so similar to Earth. By looking at the differences between them we can obtain a greater understanding of how planets 'work' than when we look at Earth alone.

Rovers can contribute to this by doing a bit of geology research. The amount of useful information doesn't come close to what scientists can do when investigating Earth, but so far they are one of the few instruments we have on other planets, and as such the information they return is of high value.

 

[tylor2000]

I think he means Olivine, a mineral.

http://en.wikipedia.org/wiki/Olivine

Yes, my stupid spelling mistakes. Thank you.

 

[Usquanigo]

and why should we even go there in the first place, it's not a sort of great holidaying spot.

And where is? It's not like we can survive on the Moon or Mars without specially designed protection. And certainly not for very long without specially designed shelters (ignore heat and pressure for a second, the lack of magnetic fields makes them treacherous places, and a thin or missing atmosphere doesn't help any either).

Venus is just the opposite problem of normal (instead of a cold vacuum, it's a hot pressure chamber). But it is closer to Earth grav, which is a good thing. And it's an enigma wrapped in a mystery (of clouds).

Why climb a mountain? Because it's there.

 

[T.Neo]

This is a new idea: so far, Mars is the only planet (besides Earth) where rovers have operated.

Well, both manned and unmanned rovers have operated on the Moon (although it isn't a planet).

Take the third largest asteroid(mostly ovaline), crumble it up into fine powder and disolve it into venus' atmosphere. Then we can all go there for vacations.

I've looked through many terraforming concepts (Mars and Venus), and of all of them yours makes the least sense- I don't see how dropping olivine onto Venus will sequester the CO2 atmosphere, improve rotation and generate sizable oceans.

Aside from the impracticalities of mining and moving entire asteroids, your concept does not seem to have any chemistry sense at all (Although, I'm not chemistry major, so I'm not sure.)

If humanity ever terraforms a planet (given the right engineering and big enough infrastructure I think it is indeed possible), it will be Mars (or Mars will be the first until technology improves or a suitable (extrasolar) candidate is found).

Mars should be far easier to terraform then Venus (the only problem is a severe lack of nitrogen).

 

[movieman]

Mars should be far easier to terraform then Venus (the only problem is a severe lack of nitrogen).

Mars is also unable to maintain an oxygen atmosphere, isn't it? At least at Earth-type temperatures.

 

[Usquanigo]

If humanity ever terraforms a planet (given the right engineering and big enough infrastructure I think it is indeed possible), it will be Mars (or Mars will be the first until technology improves or a suitable (extrasolar) candidate is found).

Mars should be far easier to terraform then Venus (the only problem is a severe lack of nitrogen).

Where would we get all that gas (of any type)? Siphon it off of Earth - and reduce it's atmosphere in the process?

Why would we create a breathable atmosphere, or even normal atmospheric pressure when taking off our space suits outside of a habitat would result in fatal UV and solar radiation burns (due to a lack of both ozone layer, and magnetic field). And how could we even create that much pressure when the gravity is so weak?

Teraforming doesn't really make sense. Plus it also corrupts the solar system, which is a bit of a crime for all humanity and all future generations. Better to just build giant habitats. That way "The Red Planet" stays red, we get to stay there without a space suit and actually relax, safe from all the hostilities of space, and don't have to spend a billion years or destroy other planets in the process of trying to do it.

 

[T.Neo]

Mars is also unable to maintain an oxygen atmosphere, isn't it? At least at Earth-type temperatures.

It should be, but estimates range from a few thousand years to a billion or more. More research would be needed.

And the atmosphere would probably be mostly nitrogen (or some other buffer gas such as argon, but the relative rarity of such gasses makes them less attractive).

The bigger problem would be hydrosphere loss due to water being disassociated by UV rays, as happened on both early Mars and Venus.

EDIT:

Where would we get all that gas (of any type)? Siphon it off of Earth - and reduce it's atmosphere in the process?

No. Aside from the ecological concerns, Earth has a large gravity well which makes gas transport impractical. Nitrogen and water would probably be sourced from outer solar system objects like comets.

Why would we create a breathable atmosphere, or even normal atmospheric pressure when taking off our space suits outside of a habitat would result in fatal UV and solar radiation burns (due to a lack of both ozone layer, and magnetic field). And how could we even create that much pressure when the gravity is so weak?

Cosmic radiation (and charged particles) don't cause fatal burns on contact (AFAIK), at least not the type you are describing. Add to that the fact that even a thin atmosphere provides shielding.
For UV, you could either attempt to synthesise an ozone layer or wear sunblock or clothing.

As for holding onto an atmosphere- I point you towards Titan. Even a small body can hold onto an atmosphere, the question is for how long.

Teraforming doesn't really make sense. Plus it also corrupts the solar system, which is a bit of a crime for all humanity and all future generations.

Compare a living, livable world to a dry, vacuous dustbowl and tell me how that is corrupting.

Better to just build giant habitats. That way "The Red Planet" stays red, we get to stay there without a space suit and actually relax, safe from all the hostilities of space, and don't have to spend a billion years or destroy other planets in the process of trying to do it.

You will not have no worries if inside a giant habitat- cosmic rays, pressure differentials and even the odd meteor impact will be an issue.
Add to that the fact that you will have to wear a spacesuit to leave the habitat (for repairs or otherwise)

And terraforming Mars won't take billions of year- the most optimistic estimates put it at even a few hundred years.

 

[ijuin]

I've looked through many terraforming concepts (Mars and Venus), and of all of them yours makes the least sense- I don't see how dropping olivine onto Venus will sequester the CO2 atmosphere, improve rotation and generate sizable oceans.
.

In the presence of atmospheric water vapor, olivine readily absorbs something like half of its own mass in carbon dioxide. Thus, in principle it should be useful for absorbing a large fraction of the excess carbon dioxide in the Venusian atmosphere.

 

[Nemoricus]

Which there is a rather distressing lack of on Venus. Seriously, it's a very dry world, so your plan wouldn't work. Sorry.

 

[Urwumpe]

How about this one?

http://solarsystem.nasa.gov/missions/profile.cfm?MCode=VISE&Display=ReadMore