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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?"
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.
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'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
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).
Be careful. People in masks cannot be trusted.