Aerial Drone To Hunt For Life On Mars 152
astroengine writes "What if the Martian terrain is too rugged for a rover to traverse? How do we study surface features that are too small for an orbiter to resolve? If selected by NASA, the Aerial Regional-Scale Environment Surveyor (ARES) could soar high above the Martian landscape, getting a unique birds-eye view of the Red Planet. Its primary mission is to sniff out potential microbial-life-generating gases like methane, but it would also be an ideal reconnaissance vehicle to find future landing sites for a manned expedition. Prototypes of the rocket-powered drone have been successfully flown here on Earth, so will we see ARES on Mars any time soon?"
first, nuclear waste, now, exhaust gases (Score:2, Funny)
Re:first, nuclear waste, now, exhaust gases (Score:4, Funny)
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Just how badly are we trying to alter the Martian environment, before we even get to walk in it?
We're not altering the Martian environment at all.
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That depends on your definition of environment. Planting our Earth manufactured robot underneath a bunch of martian sand might have profound effects in the future, butterfly and all that.
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That depends on your definition of environment. Planting our Earth manufactured robot underneath a bunch of martian sand might have profound effects in the future, butterfly and all that.
It obviously does have a profound affect on the future in that it expands human knowledge concerning Mars considerably. But the sort of effect you're refer to is not a genuine change, but just a slight bump to a chaotic system (which it is reasonable to assume Martian weather is). All the good and bad parts of martian weather would happen anyway with the same frequency and we still would be relatively clueless as to what weather is to come. So it doesn't change anything for us nor does it change anything fo
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Though we are sterilizing landers, just to be safe (I wonder how that will look with eventual manned exploration - we can produce sterile lab animals, but...) - and tenuousness of Martian atmosphere means even a miniscule additions make a noticeable difference (like that methane mystery - which, in the end, represents an exceedingly small amounts)
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Though we are sterilizing landers, just to be safe (I wonder how that will look with eventual manned exploration - we can produce sterile lab animals, but...) - and tenuousness of Martian atmosphere means even a miniscule additions make a noticeable difference (like that methane mystery - which, in the end, represents an exceedingly small amounts)
You're mixing two different definitions of "sterile". Sterile animals simply are animals which can't reproduce. They remain chock full of microbes. Sterile landers are landers that have been exposed to adverse conditions in order to kill off bacteria and other microbes on the probe. The first few long term missions to Mars may involve sterilized humans, but that's because whoever their managers are don't want the sizable risks and obligations of pregnancy and birth to interfere with the missions.
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I'm not mixing anything, you are just not aware that, with some (not too hard) effort, we do produce sterile lab animals - microbes are normally picked up only after (well, during too) birth. Useful for research about role of intestinal gut flora (and yeah, why such sterility could be problematic - though I wouldn't be surprised if not too far from current public health issues due to bad eating habits)
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No one will ever walk there (Score:4, Insightful)
No one is going to Mars: no one will ever walk there. Any announced Mars landing mission in the future will be quietly cancelled a few years after its announcement. There's not going to be any Apollo type mission to Mars.
Why do I say this?
Because the United States is broke. Not only is it broke but it is broken. Its financial system is paralyzed. The US government is too many trillions of dollars in debt. Whatever money that might have gone into a giant space project in the 20th century went instead into mortgauge fraud and pointless endless wars (that will be lost at great financial cost). The US economy is much more fragile than the government and news media is proclaiming it to be. There is no recovery, nor will there be, outside of the pronouncements of a cadre of paid-off economists and the accounting tricks of millions of government check-kiters.
There might be a project of a giant "Predator"-like drone that flys around in the Martian atmosphere, but I doubt it. Still the aerospace-NASA lobby can pull some strings and make a project like this happen. But there won't be many projects in space in the next 20-30 years. In 150-300 years, sure, who knows? But not in our lifetimes.
We haven't even begun to estimate the costs of the disruptions that will be caused by Peak Oil, Overpopulation, Global Warming, and fiscal collapse all happening at about the same time. My guess is that people will be so overwhelmed by the magnitude of these problems that any suggestion of massive space travel projects will be just laughed off.
Remember that it's easy to announce these massive space projects, and just as easy to quietly cancel them when no one but the Slashdaughters are paying attention.
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The messiah is coming back, in force, within your lifetimes! Just like he...did...the last time...wait...
the Mars Vault was the toughest yet... (Score:2)
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Yeah! Everyone knows that apples are better for your health than chocolate bars!
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Yeah, but they had to close down. Turns out that nobody wants to buy drinks on mars.
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Fortunately we have myopic bastards such as yourself to teach us the reality of space and our technology.
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The hell with your exotic threat scenarios!
If they are planning to hunt for Martian life with drones? Then as a Martian I'd be very cautious about holding any wedding parties...
UAV to hunt for life on Mars... (Score:4, Funny)
And will be carrying a Hellfire missile, just in case said life decides to get uppity.
Or just to make the end-of-life for the UAV much more exciting. Either way.
Important Message from Marvin: (Score:2, Funny)
You have made me very angry - very angry indeed!
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Yes exactly. The first thing that came to mind was "what if they shoot it down?"
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As funny as this may sound it really illustrates a point that NASA really has to bring home. Make space travel produce usable results here on Earth and understandable to the constituents that are paying the bill. UAVs should have been at the top of that list. First, you'd have to look hard to find someone of the general public that doesn't know what an UAV (unmanned drone for some) is. Second you put the angle of, "NASA. We're making UAVs so damn good they fly on Mars bitches!" people will really see t
Re:UAV to hunt for life on Mars... (Score:4, Insightful)
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I don't know which theater you were sitting in, but the 'nuke it from orbit' line was well received around here.
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Um... yes, that was his point. "Nuke it from orbit" is a line catering to audiences who might not react the same way to "drop a rock on it from orbit", because they might not see how that's equally explode-y as a nuke. :)
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For all that the rest of it was a glorious romp through suspension of disbelief land, nuking anything from orbit has never made sense to me--why not "kinetic bombardment" or something similar... probably not the same level of immediate--"ooh, that would be bad" from the audience.
Well, kinetic bombardment is tough when you are hitting a planet. If your target isn't very large and you've got an atmosphere you need something that will survive reentry or is very large. That's sort of the point of using mass drivers. In the context of the original line, they don't have any mass drivers. The ship isn't that large. Hence, nukes.
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Like http://www.youtube.com/watch?v=sCoHT_cHPzY [youtube.com] this?
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Kinetic-kill weapons would be very effective at taking out tanks, bunkers, and even ships, but they wouldn't be particularly effective at destroying things over a wide area unless either you had a lot of them, or what you were dropping was really big.
Rocket-powered? (Score:5, Insightful)
Re:Rocket-powered? (Score:4, Insightful)
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Wouldn't that make ballons better?
I'm not an expert either. In fact, I have an odd feeling I might be ridiculed for asking such a question.
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The problem there is there is no clear path for it to take. It would be at the mercy of the winds, which can reach up to 100mph.
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Such winds would be a good thing, allowing exploration of vast area over the course of a week or so.
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Re:Rocket-powered? (Score:4, Informative)
Balloons work off of the differential between the inside air pressure and the outside air pressure. If the outside air pressure is low, then even if you manage to generate a vacuum inside the balloon, the differential is still small and therefore so is the lift.
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http://lmgtfy.com/?q=ballons+mars+exploration [lmgtfy.com]
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What? I can't tell if you are trolling or on crack. "Vacuum" inside a ballon? really?
For all intents and purposes, given the same temperature and pressure any volume of gas has approximately the same molar density.
Hydrogen and Helium balloons float because they have less mass per molecule than earth air (and much less per molecule than mars air), and that mass difference is enough to make up for the relatively high density of the relatively thin balloon.
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You know what, that description isn't close to correct either, I am suffering caffeine withdrawal. But it is a lot better than "vacuum".
Re:Rocket-powered? (Score:5, Informative)
What the GP is getting as is that the theoretically most efficient aerostat you can build is one with a rigid shell and an evacuated interior. It's not really a balloon, per se, hence the confusion.
Any actual balloon full of gas will always have less density differential than this, and thus generate less lift.
In practice, the mass of extra material required to build a rigid shell generally outweighs any extra lift you could get over a hydrogen or helium balloon. Hence, you don't see evacuated aerostats outside science fiction (e.g. Diamond Age by Neal Stephenson).
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Physics FAIL
Pressures inside balloons (and anything else like water droplets for that matter) are actually higher than the ambient pressure by an amount related to the surface tension of the membrane or liquid-gas interface.
Also, bouyancy works based on density differences, not pressure differences. You can have compress air to have as high a pressure as you want and it will still float so long as the final density is less than water's.
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Balloons work off of the differential between the inside air pressure and the outside air pressure. If the outside air pressure is low, then even if you manage to generate a vacuum inside the balloon, the differential is still small and therefore so is the lift.
Balloons work on a difference in WEIGHT of the gases inside the balloon compared to the outside air that is displaced.
It has nothing to do with pressure. Hot air balloons are not sealed, they are open at the bottom. Essentially zero pressure differential.
See, those days you skipped out of science in the 7th grade to smoke weed in the park come back to bite you.
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I'm not an expert either. In fact, I have an odd feeling I might be ridiculed for asking such a question.
If you hadn't included that disclaimer, you probably would have been :) But yeah, you got it completely backwards. The higher the atmospheric pressure, the easier it is to generate lift. A balloon filled with regular air will rise just fine when submerged in water (an "H20 Atmosphere") , but won't do dick when it's in earth-normal atmosphere. If you had a pure-helium atmosphere, a helium balloon would likewise do absolutely nothing.
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I'm no expert, but since the atmospheric pressure on Mars is so low propellers/balloons etc probably won't work very well.
This guy, Dr. Alexey Pankine, a project scientist at the Global Aerospace Corporation, disagrees. http://www.spacedaily.com/news/mars-balloon-04a.html [spacedaily.com]
Re:Rocket-powered? (Score:5, Interesting)
I'm no expert, but since the atmospheric pressure on Mars is so low propellers/balloons etc probably won't work very well.
Jet engines work pretty well at low pressure with some cooling issues. The killer is you need something that burns in mostly carbon dioxide (liquid fluorine?)
The killer for propellers is its just a rotating airfoil (like a helicopter blade) and the speed of sound drops with density. And classical prop designs are an utter failure when supersonic.
The killer for balloons is a completely different problem, the overall vehicle needs to be less dense than the atmosphere it displaces. Which is just barely possible to do on earth. Not going to work on Mars.
Flying on Mars is non-trivial. See the X-Plane guys
http://www.x-plane.com/adventures/mars.html [x-plane.com]
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With all the monthly news on Slashdot of cheap amateur helium-filled balloons reaching 30+ km (conditions similar to Mars) it's suddenly barely possible and definitely won't work? (while we almost did it [wikipedia.org] over a decade ago)
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Your definition of work is apparently during a fraction of the attempts, a balloon will temporarily successfully float under ideal circumstances with an extremely small payload. Basically a martian mythbusters stunt. We'll send Kari up for some zero G shots, maybe blow something up purely for the heck of it at the end of the episode. Duct tape, lots of duct tape. Entertaining, but I don't think you can build a space program around it.
My definition of work is somewhat stricter.
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We'll send Kari up for some zero G shots
Please?????
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"Extremely small"? Just look at payloads quoted - the drone from TFA will most likely carry less (for just an hour)
What didn't work for past attempts was primarily the funding - something the UAV project also has big and longstanding problems with.
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The killer for balloons is a completely different problem, the overall vehicle needs to be less dense than the atmosphere it displaces. Which is just barely possible to do on earth. Not going to work on Mars.
Let me google that for you:
http://lmgtfy.com/?q=ballons+mars+exploration [lmgtfy.com]
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http://lmgtfy.com/?q=dictionary+balloon [lmgtfy.com]
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Almost, but not quite as useful, as deciding what rocket engine technology to use by googling for "star trek warp engine"
The problem is earth balloon payloads are very small to the point of uselessness, and momentarily just barely top out at the point where a Mars flight would have to begin ...
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Read some of the article found by Google. Most of them written by professionals in the field. They seem to disagree with your assessment.
I'm sure you've heard about balloon flights around the world. Steve Fossett RIP.
Do the math. Less gravity compensates for less atmospheric density on mars to the degree that you would only need a balloon twice as big for the same payload as on earth.
Doable.
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There are two real problems - lack of air and lack of oxygen. No oxygen means that it has to use rockets or electrically spun propellers, since jet engines burn gas and O2. A thin atmosphere means that propellers won't have much grab and even worse, the wings won't generate much lift. This thing is going to be a one-shot deal as there's no way to currently build a drone that can stay aloft indefinitely on Mars.
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Lack of external oxygen doesn't preclude ICE, as many torpedoes and some submarines have demonstrated.
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The conditions are comparable to 30+km altitude on Earth. Something a balloon can do easily, and we might do it one day [wikipedia.org], if we cared (glider [wikipedia.org] might do it, so small low-powered UAV certainly)
And TFS is incorrect - at this point ARES explores also propeller propulsion, electric or ICE.
Re:Rocket-powered? (Score:5, Informative)
Typical Mars surface air pressure varies between 6 and 10 millibars, depending upon season and land altitude. Assuming relatively low altitude flights, it's quite possible to build aircraft that can fly in that density (particularly given that Mars' surface gravity is only about 40% of Earth's). What are the constraints?
1. Velocity. At 6 millibars, you're looking at a near-supersonic speed to stay aloft. Sure, that's not a big deal from a drag perspective when the air is that thin, but your propulsion system has to be able to maintain that. Can propellers do that? Yes. The XF88B [wikipedia.org] could maintain 0.8 Mach.
2. Flutter. Unlike drag, which is heavily dependent upon the product of air density, velocity and drag coefficient, flutter is only really dependent upon airspeed. Think of it as a kind of resonance. As the air flows over the wing, the wing vibrates like a guitar string. Aircraft have literally shaken themselves apart when they hit a critical airspeed; this remains an issue today (example: builders of the Van's Aircraft RV10 are warned about relying upon airspeed indicators if they have a turbocharged or supercharged motor, as at the service ceiling of 18000 feet the absolute airspeed max of around 250 knots will only be shown as 160 knots on most mechanical airspeed indicators... and at 250 knots, you're int he danger zone for flutter). This can be engineered around, though at the airspeeds necessary it won't be easy.
3. Energy. So how do you propel this thing? Unless it's going to be a short mission, chemical propellants are right out (especially given that you need to carry both the fuel AND the oxidizer, as there's no "free" oxygen to be found. Solar-electric is being discussed, and may actually be viable; the plane would probably have to "race the sunset" to stay in sunlight constantly. This is very doable, though. At the equator, Mars has a curcumference of about 13,000 miles. At that size, with a 24.5 hour day, an aircraft would have to maintain a bit over 500mph to stay in sunlight. However, as this is likely to be near the speed necessary just to stay aloft anyway, it's a nonfactor. If you're powered enough to fly, you can stay in sunlight.
Yep. There are problems. But none of it is insurmountable. How much tax increase are you willing to endure (and convince others to endure) to accomplish this? If that number's high enough... yes. It CAN be done, with propellers and lift from wings (as opposed to vectored thrust). The challenges are the power system and overcoming flutter, but these are solvable.
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Can propellers do that? Yes. The XF88B could maintain 0.8 Mach.
That's in Earth atmosphere, though. Doesn't the efficiency of propellers directly depend on the density of air?
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Can propellers do that? Yes. The XF88B could maintain 0.8 Mach.
That's in Earth atmosphere, though. Doesn't the efficiency of propellers directly depend on the density of air?
It does, yes. Remember though that the density of the atmosphere is much lower than surface at the altitude at which those tests were performed (100mb or less). There's no question that the props won't be of the same efficiency... it's only if they're "good enough".
There's the additional issue of prop blade speed. While it's very hard to make a conventional prop work well at supersonic speed from the point of view of "how fast is the prop moving forwards", there is also the issue of "how fast are the prop
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Which is exactly why, despite being proposes pretty regularly (read: practically on an annual basis) since the late 60's - no airborne probe has yet been sent to Mars. They're hellishly expensive for very little science return.
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We've made great advances in sensor and video technology since then, and we have drones piloted remotely all over the military and also in part of the border patrol now. The technology to make it happen is more readily available than in the 1960s and the payoff with the better sensors would e higher. Whether it's enough progress to move from nonstarter to actual project is questionable, but it has to be closer than fifty years ago.
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My thinking exactly.
Put the payload on a smallish blimp like thing which you inflate after landing, and can control with solar powered motors.
Include enough helium you could make several significant altitude changes over the course of months instead of minutes.
Winds aloft would somewhat determine your course but that might be something you would want to document anyway.
Let the people who built Spirit and Opportunity build the thing. Those guys build it right.
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On Earth: The density of air at sea level is about 1.2 kg/m3
Divide by 100 (pressure difference) times 3 (lower gravity) gives 0.03 kg/m^3. Bump it up to 0.1 kg/m^3 because its CO2 (higher density) and lower temperature. So you have 12 times less lifting capability compared to Earth but one third the gravity so you will need four times the volume of the balloon for the same lifting capacity.
I suppose its doable but remember the weather balloon which got away from its handlers in Australia some time back. I
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Whats your point?
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Then we should replace the comment field with a link to google. imgtfy is used when a question is asked which google could have answered. I didn't ask a question.
But... (Score:2)
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Wrong planet, dude. Women are from Venus.
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A letter missing from the acronym (Score:5, Funny)
Aerial Regional-Scale Environment Surveyor (ARES)
Even NASA has trolls apparently
X-prize my ass! (Score:2)
ARSES (Score:5, Funny)
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Your tax dollars at work, people.
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The acronym for Aerial Regional-Scale Environment Surveyor should instead be read as ARSES... Which kinda fits for a mission looking for methane emissions and germs.
I heard they're planning on expanding mission capabilities by putting the new Planetary Exploration Nanoscale Integrated Spectrometer into the ARSES, but there is some question whether the Republican-led House will approve the additional funding necessary to fully couple the two projects.
Any time soon? (Score:4, Interesting)
Not likely. This project has been around for several years now. Here's [foxnews.com] a story where they hope to get DARPA to pay for it. And it's was already around for years before that. The problem with it? Real time control. The plane would have to be able to direct it's own flight and research with minimal input from Earth becasue of the time lag in commands. Controlling a Global Hawk or Predator from half way around the world isn't tough. Flying a UAV on another planet? That's tough. Look what happened to poor Spirit [wikipedia.org].
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You mean "Look what happened to poor Spirit" FIVE AND A HALF YEARS beyond its expected 90 day life span?
I'll take that ROI anytime.
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I think you misunderstand the issue. While it may be possible, very little if any drone flying (Predator, etc) is really live hand-flying of the airplane. You put in waypoints, tell it the altitude to fly, tell it to orbit about a point, etc, and the airplane does the actual flying. That's how the vast majority of airline flying works, too. In the case of the Mars airplane, it's actually a lot easier than a ground vehicle, since there are no obstacles aside from mountains, etc, that are already identified (
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You put in waypoints, tell it the altitude to fly, tell it to orbit about a point .... The only real problem is the power source, since it's not going to landing.
That, and the lack of a GPS constellation. Admittedly they could probably do "well enough" with inertial and ranging against the orbiter. And not much of a magnetic field for the compass. Gyros to the rescue, and I'm not talking about a greek sandwich. And the dust storms getting in the way of the star tracker.
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All of the current drones rely primarily on an inertial reference (gyros and accelerometers) for short-term control. It uses GPS to provide updates to the system to correct for drift. That would work perfectly well with Sun and satellite ranging from existing satellites.
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From what I know, the parts where you have to keep a human in the loop on terrestrial UAVs is not on basic piloting, but for redirecting it to new stations, checking targets, keeping airspaces clear, etc.
Most of these 'hard thing's for terrestrial UAVs wouldn't apply to a scientific vehicle on another planet. As for the basic piloting and station-keeping tasks, all of the military UAV research would actually make an ARES-type much easier (assuming the pertinent data can be de-classified).
Levine doesn't work on the ARES plane itself? (Score:2)
"What the airplane gives is mobility, because we can travel 500 miles an hour anywhere," he said.
The ARES plane continues to be modified at NASA Langley Research Center in Hampton, Va. Here, the plane is tested in wind tunnels to withstand winds of up to 100 mph.
Oops, I guess the plane tears itself apart.
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Or they're testing a full-scale model in one of their low speed wind tunnels and this is just another example of shitty science reporting. It is important to note that the atmosphere on Mars is significantly thinner than the one here on Earth, and wind tunnel testing usually uses Reynolds number as a similarity parameter rather than velocity, so it's completely possible that 100 mph in their wind tunnel is equivalent to 500 mph flight somewhere on Mars.
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Ooops, it looks like you forgot the difference between Earth and Martian atmospheric densities.
Too lazy/disinterested to do the math, but a 100mph Martian wind has considerably less force/energy than a 100 mph Earth wind.
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Google for the difference between indicated air speed and ground speed. Thats the first problem.
The second problem is the X-Plane simulator guys claim that indicated air speed of about 50 miles per hour (referenced to earth sea level equivalent pressure) is about the same as 500 miles per hour actual air speed on Mars.
http://www.x-plane.com/adventures/mars.html [x-plane.com]
"First of all, the atmosphere is ONE PERCENT as thick on Mars as it is on earth... INDICATED airspeed is proportional the the square root of the air
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I want a Mars ballloon/blimp (Score:3, Interesting)
Yeah, I'm sure it's not practical, but Mars apparently has some jaw-dropping vistas. I'd love to see a robotic blimp traversing the planet snapping pictures.
Landing (Score:2)
ARES will be pre-programmed to land on Mars. Once ARES has landed,
TFA doesn't say how they will get the vehicle on the ground but I am willing to bet it won't glide to an unpowered landing. More likely it will carry a small airbag or powered descent lander but I doubt it will be able to carry enough payload for a lander which can last a long time on the surface.
It's already been done! AMEE had one! (Score:2)
"Red Planet" already had AMEE (Autonomous Mapping, Evaluation and Evasion) and it had an aerial reconnaissance drone. It's right over there next to the Soviet Lander... I wish NASA would come up with something new and innovative rather than copying... It was on A&E this weekend..
"Fuck This Planet" was surreptitiously edited out.. .Fucking A&E...
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Yeah AMEE worked out great did't it.
One wonders what AMEE was supposed to evade?
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It evaded the guys on Mars who wanted the super battery....
I think all you need to conquer Mars is a few Molex connectors and a super battery and some algae
and maybe a Thermos.
Are they still looking (Score:3, Funny)
Are they finally expanding their search for Bin Laden?
craters? (Score:2)
They worked on this in the 1990's (Score:2)
I remember reading about something this in Aviation Week long, long ago.
[Engage google drive... grognard factor two...]
Aha, here we go. Aerovironment, Inc., actually tested a concept model of a drone glider for use in Martian conditions in 1999. [nasa.gov]. And according to that link, previous work had been done as early as 1996, but I didn't read it closely enough to note who built that one.
Tried to resist (Score:2)
"the Aerial Regional-Scale Environment Surveyor...Its primary mission is to sniff out potential microbial-life-generating gases like methane,
So logically, its primary sensor instrument will be called the AR-SES Sniffer.
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This joke gets funnier with every passing year. ~
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It's interesting that they tested the rocket in earth atmosphere, wouldn't it be pretty different on mars?
The only real difference is air pressure. That difference is well understood. They can compensate by enlarging the nozzle exhaust bell by a known amount.
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You can test at high altitude on Earth, possibly by deploying the aircraft from a balloon.