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Fly Over Mars... in a Robotic Balloon
Roland Piquepaille writes "A Californian company, Global Aerospace Corporation (GAR), is developing remote-controlled balloons for the NASA Institute for Advanced Concepts (NIAC). BBC News Online reports that their goal is to send these balloons carrying robots and cameras to explore Mars skies. But it's not for a near term future. The robotic StratoSail will have a stabilizing wing suspended several miles below it. It will be able to stay above Mars for months. It will send robotic probes to monitor the surface and minilabs to carry out experiments. This overview contains more details, references and images about the StratoSail."
mod this down, its a redirect to this . it'll probably redirect to tubgirl or goat.cx when it gets enough informative mod points
We certainly know a bit about the Martian atmosphere... Both the Spirit and Opportunity rovers used it to aerobrake before deploying their parachutes. Certainly not detailed knowledge, but enough to make something like this (which is self-correcting if it gets too high) workable.
In Soviet Russia, sig types you!
haven't there been problems putting one rich white dude in a manned balloon and taking it around this planet, once? with the turbulent sandstorms on mars that i've seen in movies (therefore, are real), i can't imagine that this is feasable.
"Is there enough variation in Martian winds with altitude for this system to work there?"
p or tunity/20040209a.html
Check this press release describing the shift in winds during Opportunity's landing. Scroll towards the bottom for some nice pictures describing the landing. The shift in winds may be too low in altitude to relate to the parent topic.
http://marsrovers.jpl.nasa.gov/gallery/press/op
Yeah, and this is actually an old idea that was used extensively by the Soviets during their push for planetary exploration. Since the atmosphere of Venus was so hot and dense, they were able to float the balloons with extremely heavy loads. The scheme worked well during the Venusian "night," until the sun came and expanded the volume of gas in the balloon, bursting it. The idea for balloons on Mars has been "floated" before, but it looks like it just might happen this time...
For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.
As long as the pressure from the inside is the same as the pressure on the outside, we're good to go. Assuming an ideal gas, this means the number of particles on the inside of the baloon is equal to the number of particles on the outside of the baloon. What we are really concernd about is the composition of the atmosphere, not the density. The baloon's size therefore is not related to the atmospheric pressure but rather the molar mass of the atmosphere. And as you said, gravity is weaker, so if anything I bet the baloon would be smaller than it has to be on earth.
Quid festinatio swallonis est aetherfuga inonusti?
Africus aut Europaeus?
Err... Not only can we land an airbag on Mars, but we just did it successfully. Twice.
For hydrogen to explode, it needs to be in the presence of oxygen.
This is much less a concern in the Martian atmosphere, which is 95% corbon dioxide, as opposed to Earth's 80%-20% nitrogen-oxygen mix.
As for storage and transport, hydrogen can either be well contained (rocket fuel rarely explodes prematurely these days), or generated by a chemical reaction upon arrival (anyone remember what you get from adding a metal to acid from middle school chemistry? Though I'd imagine the medium of choice would likely be something like hydrogen peroxide. IANA Chemical Engineer.)
Good points, yes the pressure needs to be the same, and your point about the number of atoms/molecules is right too, but you forgot something.
The total lifting force is equal to the absolute difference in weight between the gas inside the baloon, and the equivilant volume of gas outside. With a less dense atmosphere, that effect means much less buoyancy. Density matters a lot here.
CO2 is about 10 times as dense as helium at the same temp and pressure, so you could approximate the upward force by the weight of the equivilant volume of CO2 at that temp and pressure. since that is not very dense, you need a lot more volume.
Last, since force = constant*weight difference, gravity does not matter. Double the gravity would double the force up, and the down pull on the payload.
The computer science department at the University of Wales, Aberystwyth, UK has been working on aerobot research for several years now.. There have also been similar robots sent to Venus.
You can take virtual flyovers of Mars now. A neat website hosts virtual, controlable Mars flyovers of famous sites, including the lander sites. MarsQuestOnline has several Mars virtual flyovers, and lots of other good Mars stuff. check it out.
There is nothing so silly as other peoples traditions, and nothing so sacred as our own.
We know quite a lot.
The Soviet Mars 6 probe recorded atmospheric measurements all the way to the surface, as did the two Viking probes.
And it is routine to use measurements of the strength of signals from orbiters to measure atmospheric density. As the probe slips behind the planet, any atmosphere will interfere with the signal strength. Measure it finely enough and you can plot the varying density with altitude.
This isn't the first proposed balloon on Mars. the Soviet Union and France planned a mission for 1992, which was then slipped to 1994 then to 1996 and finally cancelled. The mission would have comprised of a heavy orbiter which would have acted as a communications relay and survey craft, a number of very small landers and/or penetrators and a pair of balloons.
The balloons would have used a combination of helium and solar heating to gain lift. The helium would provide most of the lift, the warmth of the Sun would give it bouyancy during the day. As it warmed, it would rise and drift along providing an almost constant aerial survey.
In the evening, as it cooled, the balloon would sink back to the surface - the helium would prevent the balloon snagging on the surface and keep the antennae upright. Meanwhile, instruments loaded into a long 'snake' slung below the balloon would be making surface measurements and inspecting the geology.
The balloon was tested on Earth and proved to be highly successful, it's a tragedy that the collapse of the Soviet Union prevented it flying.
Best wishes,
Mike.
A mention of prior art in balooning the other planets would be in order. Many people arent aware of the fact that Russian Venera program, what later become Vega, successfully flew two balloons in Venusian atmosphere in 1984. ....
Geoffrey Landis has a couple very thought-provoking papers on his website, regarding possible further developments of atmospheric flight on both mars and venus, and possibilities for human living in upper atmosphere
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A quick check in the Wikipedia, under the ocurrance section for Helium reassures me a little "Helium is the second most abundant element in the universe"
It's just a matter of patience ;o)