Just to add to Shankar Chaturvedi Dwivedi Shukla's answer to Why didn't NASA send an aerial vehicle to explore Mars?, there have also been several ideas for sending lighter than air balloons to explore Mars.
These work well because CO2 is a dense gas. Even though the atmosphere is thin, almost a vacuum, the balloons can be filled with a lighter type of air at the same pressure and will float, say hydrogen.
Also here have been plans to explore Mars with small RC model sized planes. One clever plan was an aircraft that could land on its tail in a kind of vertical stall, that would work on Mars which meant it could take off again.
There's also an idea to launch dozen of gliders from high altitude as you come in to Mars, to explore the Valles Marineres, say, close up images of it, as they glide down to the surface.
NASA I think tend to be a little conservative. Naturally as there is a lot running on the missions, which cost hundreds of millions or billions.
But perhaps there would be a place for something much smaller? At one point they hoped to launch lots of lightweight missions to Mars from the space shuttle, back when they thought there would be dozens of shuttle missions a year. But that didn't happen.
Still, it is something we could do. Other ideas include bouncing, or hopping rovers, and rovers that fly like a bumble bee, something that works in a large scale only on Mars.
Here the idea is to use solar powered balloon rovers which don't land at all - so missing out one of the most dangerous steps in the landing sequence.
This is project Archimedes - a 2009 mission by the German Mars society which never flew.
Or they could try the Solar Montgolfiere Balloons for Mars
This is an idea that's been suggested, but not actually tried. It has the advantage again - that though you do get there eventually, you don't land on Mars right away.
You have a long flight down to the surface. In some of the ideas - it is a single flight to a crash landing on Mars, and that's it - still worth doing with images sent back all the way.
But in others (I don't think this is widely known) - then you can land at the end of your flight, and can take off again. So - if it fails - you have all the images from the first flight down.
Then, if you land successfully - you have a lander on Mars. And if you take off again - you have shown lots of new technological capabilities that neither NASA or anyone else has achieved yet, and can have an extended mission.
The problem with large scale conventional planes on the surface of Mars is that the take off speed is well over 200 mph, so it is impractical to launch from the surface. You can deal with that by launching it from orbit, but though useful, it has to be a one off flight. When you run out of fuel, you land (or crash) on the surface, and your flight is over for good.
NASA has explored many different flying vehicles of this type for Mars, but none of them have actually flown.
It is much more interesting if your plane can take off and land again. NASA have explored that as well, smaller, model airplane sized planes with a camera and a radio.
After a vertical tail first landing like this, your airplane could take off again, using the same thrusters. This is a plane that could land on the surface of Mars and then fly again repeatedly. Essentially, it's a design for a miniaturized Mars version of VTOL flight.
In the early days of the space shuttle, the plan was to fly a space shuttle every week. One of the things they could do with all those launches is to send lots of airplanes to Mars for close up exploration of the surface.
This is an example of an entomopter, which flies like a bumble bee but on Mars can be far larger because of the thin air.
Video of Robert Michelson's entomopter.
On Mars it might be easier for machines to fly with insect type flight with rapidly beating wings, using the bumble bee wings vortex effect for lift. On Mars that can work scaled up to wings a meter across because of the thin atmosphere also assisted by the low gravity. That's the idea of the entomopter.
Small, spherical microbots filled with minature fuel cells, instruments and an artificial muscle for hopping
Microbot Madness: Hopping Toward Planetary Exploration
They could fit a thousand of these into 174 Kgs.
Penelope Boston also talks about them here - for exploring caves on Mars.
Extract from my:
Soaring, Buzzing, Floating, Hopping, Crawling And Inflatable Mars Rovers - Suggestions For UAE Mars Lander
These work well because CO2 is a dense gas. Even though the atmosphere is thin, almost a vacuum, the balloons can be filled with a lighter type of air at the same pressure and will float, say hydrogen.
Also here have been plans to explore Mars with small RC model sized planes. One clever plan was an aircraft that could land on its tail in a kind of vertical stall, that would work on Mars which meant it could take off again.
There's also an idea to launch dozen of gliders from high altitude as you come in to Mars, to explore the Valles Marineres, say, close up images of it, as they glide down to the surface.
NASA I think tend to be a little conservative. Naturally as there is a lot running on the missions, which cost hundreds of millions or billions.
But perhaps there would be a place for something much smaller? At one point they hoped to launch lots of lightweight missions to Mars from the space shuttle, back when they thought there would be dozens of shuttle missions a year. But that didn't happen.
Still, it is something we could do. Other ideas include bouncing, or hopping rovers, and rovers that fly like a bumble bee, something that works in a large scale only on Mars.
BALLOON ROVERS
Here the idea is to use solar powered balloon rovers which don't land at all - so missing out one of the most dangerous steps in the landing sequence.
This is project Archimedes - a 2009 mission by the German Mars society which never flew.
Or they could try the Solar Montgolfiere Balloons for Mars
MICRO GLIDERS ON MARS
This is an idea that's been suggested, but not actually tried. It has the advantage again - that though you do get there eventually, you don't land on Mars right away.
You have a long flight down to the surface. In some of the ideas - it is a single flight to a crash landing on Mars, and that's it - still worth doing with images sent back all the way.
But in others (I don't think this is widely known) - then you can land at the end of your flight, and can take off again. So - if it fails - you have all the images from the first flight down.
Then, if you land successfully - you have a lander on Mars. And if you take off again - you have shown lots of new technological capabilities that neither NASA or anyone else has achieved yet, and can have an extended mission.
The problem with large scale conventional planes on the surface of Mars is that the take off speed is well over 200 mph, so it is impractical to launch from the surface. You can deal with that by launching it from orbit, but though useful, it has to be a one off flight. When you run out of fuel, you land (or crash) on the surface, and your flight is over for good.
NASA has explored many different flying vehicles of this type for Mars, but none of them have actually flown.
It is much more interesting if your plane can take off and land again. NASA have explored that as well, smaller, model airplane sized planes with a camera and a radio.
NASA's Langley Research Center Artist's concept of the Mars Airplane - one of many ideas - this is a tiny plane with five foot wingspan which folds to fit into an aeroshell for entry into the Mars atmosphere.With one of these planes they found a way to put it into a stall at a 70° angle towards the ground, They found that in this configuration, it falls reasonably slowly, rather like a parachute. The plan was to add thrusters for a vertical soft landing on the Martian surface.
After a vertical tail first landing like this, your airplane could take off again, using the same thrusters. This is a plane that could land on the surface of Mars and then fly again repeatedly. Essentially, it's a design for a miniaturized Mars version of VTOL flight.
In the early days of the space shuttle, the plan was to fly a space shuttle every week. One of the things they could do with all those launches is to send lots of airplanes to Mars for close up exploration of the surface.
ENTOMOPTER - FLYING SUPER SIZED BUMBLE BEE ON MARS
This is another lightweight flying machine that could take off from a surface lander, and again, suitable for a small lightweight prototype mission.This is an example of an entomopter, which flies like a bumble bee but on Mars can be far larger because of the thin air.
Video of Robert Michelson's entomopter.
On Mars it might be easier for machines to fly with insect type flight with rapidly beating wings, using the bumble bee wings vortex effect for lift. On Mars that can work scaled up to wings a meter across because of the thin atmosphere also assisted by the low gravity. That's the idea of the entomopter.
HOPPING MICROBOT SWARMS TO EXPLORE SURFACE AND CAVES
Yet another idea, even smaller robots.Small, spherical microbots filled with minature fuel cells, instruments and an artificial muscle for hopping
Microbot Madness: Hopping Toward Planetary Exploration
They could fit a thousand of these into 174 Kgs.
Penelope Boston also talks about them here - for exploring caves on Mars.
Extract from my:
Soaring, Buzzing, Floating, Hopping, Crawling And Inflatable Mars Rovers - Suggestions For UAE Mars Lander
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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