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Aerial Drone To Hunt For Life On Mars

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?"

27 of 152 comments (clear)

  1. UAV to hunt for life on Mars... by Chris+Burke · · Score: 3, 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.

    --

    The enemies of Democracy are
    1. Re:UAV to hunt for life on Mars... by eleuthero · · Score: 3, Insightful

      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.

  2. Rocket-powered? by gman003 · · Score: 4, Insightful

    Wouldn't something less fuel-hungry give a longer usable life, and thus be a better return on investment? Solar-powered propellers, or just a helium balloon, might make more sense, as every gram of fuel takes away from the payload.

    1. Re:Rocket-powered? by Biogenesis · · Score: 3, Insightful

      I'm no expert, but since the atmospheric pressure on Mars is so low propellers/balloons etc probably won't work very well.

    2. Re:Rocket-powered? by vlm · · 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

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    3. Re:Rocket-powered? by edumacator · · Score: 2, Informative

      Wouldn't that make ballons better?

      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.

    4. Re:Rocket-powered? by Lord+Byron+II · · Score: 3, 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.

    5. Re:Rocket-powered? by sznupi · · Score: 2, Insightful

      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 over a decade ago)

      --
      One that hath name thou can not otter
    6. Re:Rocket-powered? by MichaelSmith · · Score: 2, Interesting

      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. If this one has to launch from the ground without people holding the wires then there are going to be some problems.

    7. Re:Rocket-powered? by Anonymous Coward · · Score: 3, Informative

      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.

    8. Re:Rocket-powered? by icebike · · Score: 2, 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.

      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.

      --
      Sig Battery depleted. Reverting to safe mode.
    9. Re:Rocket-powered? by Caerdwyn · · Score: 4, 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 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.

      --
      Everybody gets what the majority deserves.
    10. Re:Rocket-powered? by snookums · · 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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    11. Re:Rocket-powered? by icebike · · Score: 2, Informative

      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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      Sig Battery depleted. Reverting to safe mode.
    12. Re:Rocket-powered? by sznupi · · Score: 2, Informative

      "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.

      --
      One that hath name thou can not otter
    13. Re:Rocket-powered? by Caerdwyn · · Score: 2, Informative

      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 blades moving rotationally". When you take into account the forward motion and the rotary motion, the path a blade takes through the air is a helix. And depending upon how fast the blade is rotating and how far away from the central axis you are, part of the blades may be supersonic near the tips while near the root they're subsonic, and you have a sonic transition sliding back and forth along the blade. This is nothing new; World War II era craft had this as an issue. Brute strength solved in then, exotic materials and geometry will solve it this time.

      You also can adjust the pitch of a propeller, i.e. the angle at which the blades are tilted, in response to airspeed and density. You can pitch for climb rate, or for speed, and you can do so in flight. This is extremely common even in ordinary single-engine aircraft, and is well-understood.

      In all, as long as the true airspeed of the Mars flyer is subsonic, if there's enough atmosphere for lift there will be enough atmosphere for propeller-based thrust. Propellers are just rotating wings, and they have to solve the same problem.

      --
      Everybody gets what the majority deserves.
  3. A letter missing from the acronym by KDR_11k · · Score: 5, Funny

    Aerial Regional-Scale Environment Surveyor (ARES)

    Even NASA has trolls apparently

    --
    Justice is the sheep getting arrested while an impartial judge declares the vote void.
  4. ARSES by CosmicRabbit · · Score: 5, Funny

    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.

  5. Any time soon? by fructose · · Score: 3, Interesting

    Not likely. This project has been around for several years now. Here's 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.

  6. Re:first, nuclear waste, now, exhaust gases by biryokumaru · · Score: 3, Funny

    Ya, we're just running our A.R.S.E.S. all over it, aren't we?

    --
    When you're afraid to download music illegally in your own home, then the terrorists have won!
  7. I want a Mars ballloon/blimp by GodfatherofSoul · · Score: 2, 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.

    --
    I swear to God...I swear to God! That is NOT how you treat your human!
  8. Re:Levine doesn't work on the ARES plane itself? by Anonymous Coward · · Score: 2, Interesting

    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.

  9. Important Message from Marvin: by Anonymous Coward · · Score: 2, Funny

    You have made me very angry - very angry indeed!

  10. Are they still looking by ArhcAngel · · Score: 2, Funny

    Are they finally expanding their search for Bin Laden?

    --
    "A person is smart. People are dumb, panicky dangerous animals and you know it." - K
  11. Re:first, nuclear waste, now, exhaust gases by khallow · · Score: 2, Informative

    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 for any Martian life that happens to be there. The environment is not the second to second changes in Martian weather. It's the long term stuff which remains after you filter out the short term chaotic noise.

  12. Re:first, nuclear waste, now, exhaust gases by khallow · · Score: 2, Informative

    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.

  13. No one will ever walk there by Simonetta · · Score: 3, 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.