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Robert Zubrin's Mars Gashopper Airplane 124
Fraser Cain writes "Universe Today has a story about Robert Zubrin's (Mars Society President) Martian Gashopper Aircraft proposal to NASA. It uses solar power to liquefy carbon dioxide and then use it as a propellant to take off, fly hundreds of km above the surface of Mars like an airplane, and then land vertically again."
Here and now? (Score:5, Interesting)
Re:Here and now? (Score:5, Funny)
I guess if you only travelled a few hundred yards a month, it might work.
I'm pretty sure gravity is an issue, though. Gravity's a real bitch. Newton should never have invented it. Or he should have at least patented it so noone could use it.
Physics Buttons (Score:4, Funny)
The physics club at the local university used to sell buttons that read "Friction is a drag", and "Gravity is a downer".
Re:Physics Buttons (Score:1, Funny)
Re:Physics Buttons (Score:1, Troll)
Re:Here and now? (Score:5, Informative)
Re:Here and now? (Score:4, Insightful)
Re:Here and now? (Score:1)
Re:Here and now? (Score:5, Informative)
Re:Here and now? (Score:3, Informative)
Re:Here and now? - Thin martian atmosphere (Score:2, Informative)
The other side of the coin is that an Earth vehicle can save energy by using lift to take off horizontally, because the atmosphere is thicker. A martian one will probably need to take off vertically, and won't experience lift until it reaches a much higher cruising speed. Once at that speed, it can fly a long way without as much drag, but once you want to land you have to worry about slowing down, so the device had better measure its fuel carefully or have a large wingspan that is retracted just before la
Re:Here and now? (Score:3, Informative)
Re:Here and now? (Score:2)
Ok, I need to find some work to get done...
Re:Here and now? (Score:2)
Interesting question. From the article: The simplest gashopper could actually be quite light, as little as 50 kg (110 pounds). That's using Earth gravity conversions. The same 50 kg would weigh about 41 lbs on Mars.
But this little beast will use most of its propellant on forward motion, and acceleration relates to mass, not weight. Density of atmosphere will be the other factor, affecting the amount of lift the wings generate.Re:Here and now? (Score:5, Informative)
Do martians use the imperial system now?
For the imperial impaired (like me) 41 lbs == 18,6 kg
Re:Here and now? (Score:2)
Re:Here and now? (Score:2)
F = m * a
Just multiply for 9,8 here in Earth and for 9,8 * 3/8 (or whatever) in Mars.
Re:Here and now? (Score:1)
Interesting (Score:5, Interesting)
Re:Interesting (Score:5, Insightful)
Re:Interesting (Score:4, Informative)
Only so long as the bottom of the chasm has quite a bit of open and reasonably flat terrain, and as long as the chasm is several times wider than the wingspan of the Gashopper. (And the winds are low.)
All this become possible once we develop terrain avoidance software considerably more sophisticated than the current generation, and a computer considerably more powerful, yet lighter and less watt hungry than the current generation...
In short, this is a typical Zubrin proposal. Long on wildly handwaving the advantages (while throwing darts at NASA), and very short on a realistic assesment of the problems and challenges that lay between here and there.
Re:Interesting (Score:1)
Re:Interesting (Score:3, Insightful)
The terrain might be completely different 100km or so away, but the dirt thats 10 feet from here is probably exactly the same as the dirt you're currently on.
This thing would no doubt have more luck stumbling upon a deposit of water ice or finding bacteria or something of the sort.
The article talks about this being a good way to blast off if you wanted to make a return trip back
Re:Interesting (Score:2)
It's all about (Score:2, Insightful)
This will allow us to get a more general picture of specific areas of the planet Mars, rather than the ant-like views that we get from the rovers; that's not to say they aren't important. They are, because they give us very specific information.
It'll be really nice to see this project eventually re
Re:Interesting (Score:2)
Re:Interesting (Score:3, Informative)
Re:Interesting (Score:5, Insightful)
In any case, landing in one or two spots tells us about those spots, but we'd really like to know about over overall structure of the planet. On Earth, for example, we have big structures like the Canadian Shield. Landing on one spot and then moving around will tell you that, yep, you got granite over here, too. What we'd like to do is sample on a coarse scale, so we could see that a few 100 km away we've got completely different geology.
That's where the gashopper comes in. It's an extremely clever concept. The Martian atmosphere is mostly CO2, and the cycle of boost, glide, land and recharge could go on for a long time. It's a great way to explore a new planet on a scale that's never been done before.
--Tom
Re:Interesting (Score:3, Funny)
On behalf of the pedants, I must make two observations. First, it's GNU/areology--the capitals are important.
Second, it's only appropriate to use the GNU prefix if the Magratheans [wikipedia.org] have provided full blueprints for Mars along with the distributed, completed planet. Said plans must be under the GNU GPL (General Planet License).
Glad I could help out.
Re:Interesting (Score:2)
Do you often have problems with your jewelry criticizing your writing? Mine is oddly silent on the issue.
Re:Interesting (Score:2)
Unless this thing has a reusable airbag mechanism.
Re:Interesting (Score:2)
Re:Interesting (Score:2)
Mycroft
Re:Interesting (Score:1)
Liquefy CO2? Fly on Mars? (Score:1, Funny)
Or maybe I'm a Luddite. It just seems like an unusual focus for one's life's work.
Oh yeah, and I have to make an obligatory "global warming" mention, just like everyone else.
Re:Liquefy CO2? Fly on Mars? (Score:2)
Considering that they are going to liquefy the CO2, I think that the fact that Mars is very, very cold is an important factor in their plan.
But I guess you can't say the words "atmospheric CO2" in public without people parroting "global warming". Nevermind the fact that it's extraterrestrial CO2 we're talking about...
Re:Liquefy CO2? Fly on Mars? (Score:1)
Nose full of "science" (Score:5, Funny)
Reporter: "Yes Mr. Zubrin, it's certainly an impressive design. What will be in the nose of the craft?"
Mr. Zurbin: "As you can see from this diagram, the nose of the craft will contain "science". Next question."
Re:Nose full of "science" (Score:1)
"It's a trap! Get those ships away from the Creationism deflector shield!"
Am I the only one... (Score:5, Funny)
(No offence to any russian mad scientist having hang-over mind you....)
Re:Nose full of "science" (Score:1)
Liquifying CO2? (Score:5, Interesting)
Its a good idea NOT to have to import hydrocarbons as the nearest filling station is back here, far far away. CO2 is pretty plentiful.
The wings holding the solar panels would have to be self-cleaning though.
Re:Liquifying CO2? (Score:2)
Re:Liquifying CO2? (Score:5, Informative)
It does under Earth's amospheric conditions. You can liquefy CO2 by putting it under high pressure (5+ atmospheres, IIRC). When they release the liquid CO2 it'll probably produce gas and small crystals that will sublimate away, like what happens when you discharge a CO2 fire extiguisher on Earth.
It would be neat to watch a rocket powered aircraft that trails dry ice snow instead of smoke and flames...
Re:Liquifying CO2? (Score:3, Interesting)
Well, they'll have pressurized CO2 on hand, they could use some of it to dust off the sloar panels.
If the output of the panels drops below a set threshold, simply blow the dust off with a little bit of the propellant (it must take quite a whole lot more of it to lift the 100lbs craft than it would take to clean its wings).
And another thing... (Score:1, Funny)
Re:why even worry? (Score:5, Insightful)
How will this hurt the planet? All they are doing is using solar energy to compress CO2 into liquid form, then heating it back up again to make it rapidly expand back into gas form, giving thrust. This is no different then compressing a bunch of air here on earth and then spraying it back out again. I dont see how this could possibly hurt the enviroment.
Re:why even worry? (Score:5, Funny)
Re:why even worry? (Score:5, Funny)
On a more general note, it frustrates me whenever I hear people comment that we shouldn't pollute the moon, or throw nuclear waste in to the sun -- as if these places had a delicate ecosystem that some human-defined "pollution" would upset. There is so much room in the universe; in the end, only loony environmentalists care whether a hundred thousand tons of used beanie babies end up "recycled" on earth, or dumped on the moon.
Re:why even worry? (Score:2)
As an added bonus, there's no more geothermal energy to gain from the planet and it's too far away from the sun to farm a significant amount of solar energy, so one could say definitively that mars is here and forevermore useless.
Did you forget about strip mining?
Re:why even worry? (Score:4, Funny)
Sorry but this probe does not damage mars in anyway. it adds no CO2 to the atmosphere. We should not worry about it because there is nothing to worry about.
Kinda small (Score:1, Offtopic)
- ...but Mr Burns...
- *click* Hop in.
"the gashopper would need (Score:3)
This may well be a feature. Conventional wisdom, when fishing or hunting, is it pays not to move around too much.
Easily tested on earth too.
A really big one might help with moon mining as proposed here [abc.net.au]. Of course it would literally have to hop as wings are useless on the moon. Low gravity may make the concept practical and gas could be 'waste' from the He3 extraction.
Imagine a whole mining-processing plant hopping about the moon.
So close, and yet... (Score:3, Informative)
The plan is to use stored, compressed atmospheric gasses as propellant for a winged aircraft.
Sit back, and think about this for a second.
Now, tell me again about how this would work on the moon except for the wings.
Re:So close, and yet... (Score:4, Informative)
Whoa there Bubba!
I said, "Of course it would literally have to hop as wings are useless on the moon. Low gravity may make the concept practical and gas could be 'waste' from the He3 extraction."
You might also run a fusion reactor on the moon using some of the He3 you've mined and use the heat to vaporize and accelerate other byproducts of mining such as metals.
Links. http://www.space.com/scienceastronomy/helium3_000
Gotta think outside the bathtub
Re:So close, and yet... (Score:2)
Whoa there Bubba!
We can't even run those on earth yet.
Look at the diagram in the article (Score:5, Funny)
Re:Look at the diagram in the article (Score:3, Funny)
Grasshoppa! (Score:3, Funny)
When you snatch the CO2 from the air, then it will be time for you to leave.
confucious
About Time (Score:5, Funny)
Re:About Time (Score:2)
How would you "fly" it? (Score:2, Interesting)
If the latter, what's the advantage over, say, one of those tumbleweed style bots. What about a tumbleweed with "brakes", that can stop, expore, then curl back up into a ball and move along?
Mars exploration sounds like a candidate for the KISS principle to me.
Re:How would you "fly" it? (Score:2)
Re:How would you "fly" it? (Score:1)
Although I'm sure the cost of a venture like that would be prohibitive for a long time to come, I don't see gashoppers being launched there anytime soon either.
This thing could also yield the benefit of loads of aerial photography to chart the surface with. Pictures from orbit are nice, but aerial photography is nicer still.
Re:How would you "fly" it? (Score:2)
I think there's about a 6 minute delay both ways...
But have you never heard of artificial intelligence, autonomous robots, and autopilot? The thing could be told to go to places selected on topographical maps and fly there autonomously...it's not like there's a lot of air traffic to worry about. There's
I've got (Score:1)
THIS IS FINE, JUST MAKE SURE... (Score:1, Funny)
HAahhahahah get it!?
Oh, fuck off you aren't funny either.
Re:Christ go outside... (Score:1)
So I have nothing better to do. Too bad for you, chimpy mcgee.
Wouldn't a prop be more efficient? (Score:2)
OR, we could reroute the contents of that forward compartment into the engine and create the world's first science-powered vehicle...
Re:Wouldn't a prop be more efficient? (Score:1, Insightful)
Re:Wouldn't a prop be more efficient? (Score:2)
wtf?! (Score:1)
completely ignore terrain? (Score:1)
Don't dream of Mars planes yet (Score:5, Interesting)
His findings: low gravity and ultrathin atmosphere are bitches.
For one, the ultrathin atmosphere (air density 1% of the Earth's) requires huge wings and a very high speed to generate enough lift.
Taking-off and landing are almost impossible. The planes needs a speed of 400 knots to take off. Landing is very... hard because low gravity prevents you from using brakes, and low air density from using reverse thrust.
Of course, the Gashopper isn't supposed to take off or land (it could not anyway). However, it'd still need massive horsepower and huge wings - all of which make it hard to cram the Mars plane into a space probe.
Bottom line: if the plane has been successfully tested on Earth, it is unlikely to work on Mars.
Disclaimer: I am not a Mars aerospace engineer. But that guy's findings were definitely interesting.
Re:Don't dream of Mars planes yet (Score:2)
It's even worse than I thought. It just won't fly.
Re:Don't dream of Mars planes yet (Score:3, Informative)
Once it hits altitude, it begins to fly; it's going to need a huge wingspan to do that, true, but it can get most of the speed fro
Re:Don't dream of Mars planes yet (Score:2)
His findings: low gravity and ultrathin atmosphere are bitches.
From RTFA, I got the feeling that the plan is for the wings to be mostly controll surfaces, and that the lift would come from the jet of CO2.
Of course, the Gashopper isn't supposed to take off or land
Vertical take off and landing using jets.
I'm sure the good people at NASA's jet propulsion lab are gonna run the numbers better than "some dude"
Re:Don't dream of Mars planes yet (Score:2, Interesting)
huge wings - all of which make it hard to cram the Mars plane into a space probe
Wouldn't be all that though: the first thing that comes to MY mind is an (essentially) inflatable wing - the solar panels can be flexible, and adding some lightweight shape-memory metal (nitinol) reinforcing members might do the trick. "flying" doesn't have to mean "go FAST", just "go". In fact, going slow would have its benefits: more time to detail the terrain thats being flown over.
Re:Don't dream of Mars planes yet (Score:2)
The lower the atmospheric pressure the higher your stall speed.
Mycroft
Re:Don't dream of Mars planes yet (Score:1)
Re:Don't dream of Mars planes yet (Score:2)
Not shure how accurate his simulation is, but Xplane has a fairly high rep for a pc simulator (unluss I'm confusing it with another simulator) so it's not likely off by much.
We are the real Martians (Score:1)
110 LBS (Score:2, Insightful)
O.T. Mars Society question (Score:2)
He's not the only one.... (Score:5, Informative)
Check them all out at: http://sbir.gsfc.nasa.gov/SBIR/sbir2004/phase1/aw
Re:He's not the only one.... (Score:2)
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That's one I'm not shure I want to understand
*emphasis mine
Mycroft
If it was anyone else but Zubrin... (Score:3, Insightful)
Re:If it was anyone else but Zubrin... (Score:1)
Anecdotally, I recall hearing that the size/weight specs for the Hubble are the same for the last generation KH-?? optical spy satellites; these were also made as large as possible, for the same reason: to make the mir
Re:If it was anyone else but Zubrin... (Score:2, Interesting)
Make more, and simpler, probes (Score:1)
it's a great idea (Score:2)
Grasshopper ferries (Score:2, Insightful)
I don't understand... (Score:1)
Why not just make a helicopter ?
Atmosphere is thin, but if they can fly conventional wing in it, why not use rotor blades ?
Since they would probably have to be big, they could mount sollar cells right on the blades.
That could take care of the dust buildup too...
Re:RTGs? (Score:5, Insightful)
You need to learn a little about how RTGs work and how ridiculously clean and safe they actually are.
Re:RTGs? (Score:2, Insightful)
I think their concern is that hydrocarbons in the soil will make it difficult to work out what the soil is really made of.
Radioactive metals in the RTG can't confuse chemical analysis, even if they are released during the landing
Re:RTGs? (Score:5, Informative)