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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?"
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.
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!
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.
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
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.
http://michaelsmith.id.au