Could a drone aircraft fly in the Jovian atmosphere?

[halman]

Thalion,<br /><br />Clarke did a wonderful job of describing a Jovian atmospheric manned probe, using a hot hydrogen (the primary component of the Jupiter atmosphere) balloon. Leaving out the purely science fiction aspects of discovering life, and the 'Wheels of Poseidon' effects of shock waves in the Jovian atmosphere, his treatment of the mechanics of inserting a probe, handling telemetry, and returning to orbit were excellent. All we need is a portable fusion reactor, which is becoming more and more likely, especially in the time frame such a mission is likely to take place in. (100 years plus.) The thing that I find the most daunting is the velocity of rotation. A 10 hour day on a planet that size means traveling pretty darned quick, which tends to produce turbulence.<br /><br />Personally, I consider atmospheric probes of the gas giants to be pretty far down the list of priorities, as we will benefit far more in terms of economic paybacks from surveying the Asteroid Belt, and mining Mercury. The atmosphere of Titan will probably come after those projects, as it offers a rich source of hydrocarbons in a shallow gravity well. Mining the rings of Saturn for water ice will certainly be a contender as well. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[JonClarke]

Fortunately scientific research isn't driven only by economic priorities. In would be sad world if it was.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[vonster]

This is a really interesting topic, with a lot of interesting points raised but as of yet I dont see anyone raising this one:<br /><br />The "turbulence" and weather unpredictability on a gas giant are probably so far off the scale of what we can relate to on earth .. .. that anything we manage to get down there (at any level of current tech) would probably not last long enough to make it worthwhile.<br /><br />ie. not only are there "downdrafts" and storms larger than our entire planet, then therefore there are probably "tiny" downdrafts, surges, and storms that are only ... oh say ... the size of asia. All over the place.<br /><br />I think if we could manage to overcome all those obstacles previously mentioned ... unless we manage to overcome this one, (storms and downdrafts the size of continents, or lighting and chemical storms 1000x more powerful than anything weve ever measured) ... <br /><br />.. the most likely scenario is that our multibillion dollar blimp would be lucky to last a day or two, then *poof* ... <br /><br />... silence. And we would never know what hit it, because it would happen so fast we wouldnt get enough data to determine what it was.<br /><br />.

 

[vonster]

In other words:<br /><br />Really cool idea, but step back and consider what it is you are actually getting yourself into here <img src="/images/icons/smile.gif" /><br /><br />.

 

[thalion]

Re Halman:<br />I respectfully disagree on the importance of Jovian atmospheric probes. So far as we know, the gas giants are the only planets in the Solar System besides Earth that have vigourous convective atmospheres, evidenced by "anvils", storms, and lightning.* There is a great deal we don't know about their chemistry or coloration, and studying the atmosphere on a planet so similar to Earth in some ways (e.g., with a thick, active troposphere) and so unlike it in others (no land, strong internal heat, wholly different composition) could teach us volumes about atmospheres as a whole.<br /><br />Then again, I admit a long-running bias favoring the atmospheres of the gas giants. Heck, atmospheres in general; in some ways I'm more interested in the Martian atmosphere than in the surface. I was *so* disappointed when I learned that the MERs had no met station, and so thrilled when I found out that Phoenix will. <img src="/images/icons/wink.gif" /><br /><br />Re Vonster:<br />Ditto. Hence my idea of sending a cheap VEGA-type balloon to dip our feet in, so to speak. <img src="/images/icons/wink.gif" /><br /><br />*Venus has also a thick, convective atmosphere. However, IIRC, it lacks the vigorous vertical motion of the Jovian or terrestrial atmosphere, and has no (confirmed) lightning.

 

[ldyaidan]

My thoughts too...With what I'm hearing, it seems likely that any balloon type probe would be shredded by the winds very quickly. What if we were to instead release a lot of smaller probes, designed to send back readings as they drop through the atmo? (kind of like a pong sat, or even the sensors they designed in the movie "Twister" as an example). We could release dozens, or even hundreds of these in different locations, and record the readings for further study.<br /><br />Rae

 

[scottb50]

A baloon might make sense for Titan. With an RTG source to keep sensors warm as well as control the height of the baloon it could operate for a long time. Maybe even lower a scoop to pickup samples that could be reeled up for analysis. <div class="Discussion_UserSignature"> </div>

 

[halman]

vonster,<br /><br />If we do drop any kind of airship probe into Jupiter's atmosphere, it will have to be made quite differently than any airship used on Earth. Metal foils might work for an envelope, or perhaps a silicone/Kevlar envelope would withstand the stress. But whatever form of flying machine we use, it will have to have advanced artificial intelligence, to cope with rapidly varying conditions. Remote control, even from Jupiter orbit, will probably not work, because of the signal delay. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[JonClarke]

What you are describing are called dropsondes. They are extensively used by hurricane researchers. Parachuted instumented probes are dropped from aircraft to prtovide information on ditins at multiple leveles below the parent aircraft.<br /><br />Thus the Galileo probe was a dropsonde. You would a program of these to determine conditions in the Jovian atmosphere before you started designing any kind of aircraft and slected the areas where you released them.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[halman]

JonClarke,<br /><br />I agree that scientific research is beyond economic valuation, as playing around by educated people is how most of our technology has been created. But there comes a point when finding someone to foot the bill is very difficult, because the research instruments are extremely expensive, and the possibility of any kind of payback is remote. We could have spent all the money used in space exploration for probes to other planets, and gained tremendous amounts of knowledge. But we probably would not have developed things like microprocessors, biotelemetry, cordless drills, light weight insulation, advanced ceramics, and many other things that have been a result of manned exploration.<br /><br />If we can realize economic gain from mining the Moon, processing material in microgravity, and harvesting solar power, than there will be more money available to indulge in investigating the atmosphere of Jupiter, for instance, which offers little hope of economic return. Increasing the overall wealth of our economic system creates benefits for all, which is the most practical and concrete justification for research and exploration of any kind. Utilizing off planet resources to produce goods outside of the Earth's environment offers more opportunity for economic growth than anything else we can do at this time. Putting aside our scientific exploration temporarily to concentrate on developing economic benefits makes it far more likely that we will be able to perform such exploration in greater depth and degree. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[halman]

Thalion,<br /><br />I submit that the atmosphere of Earth and the atmosphere of Jupiter are two entirely different systems, in that the energy in the Earth's atmosphere comes from the Sun, whereas the energy in Jupiter's atmosphere is internally generated. Similarities do exist, of course, but they are probably a result of the characteristics of fluid dynamics. The incredibly rapid rotation of Jupiter also will affect any models of atmospheric convection, to the point that applying what we learn there to Earth's atmosphere would be unlikely. And the depth of Jupiter's gravity well is also going to affect everything.<br /><br />The presence of water vapor in Earth's atmosphere creates a dynamic which produces most of the really powerful convection systems we see, which is probably why neither Venus nor Mars have the cyclonic storms we experience. The agent that fills that role on Jupiter is likely to be a hydrocarbon, with a low temperature of evaporation. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[JonClarke]

Modelling different atmospheres feed directly into understanding how our atmospheres work. Different planets provide observational tests of these models.<br /><br />Examples include: Venus provides observational tests of the role of convection. Mars tests the models on the impact of oceans on atmosphere dynamics. Jupiter can validate models on the effect of rotation. many other examples can be given.<br /><br />Studies of the atmospheres of Venus, Mars, and Titan have already been very fruitful in improved models of terrestrial climate and atmospheric chemistry. These have included nuclear winter, asteroid winter, CFCs and ozone depletion, the role of CO2 and methane as greenhouse gases.<br /><br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[comga]

"I have yet to see anyone address how to get the aircraft out of its atmospheric entry vehicle. So how do we deliver such a vehicle?"<br /><br />There were proposals in the 80's and 90's for airplanes in the Martian atmosphere. They were launched from the parachutes, much as the Viking and Phoenix landers, except that they dive to gains speed and then fly a minimum descent rate profile, and they have to unfold before dropping. <br /><br />One of these proposals was called Kitty Hawk IIRC and proposed for the 2003 centennial of the Wright Brother's flight at the beach of the same name.