What is the wind speed of gas giants in terms of Mach #'s?

[willpittenger]

If we send aircraft to a gas giant (or at least a gas giant in our solar system), we need information on wind speeds. The ideal aircraft would be a lighter-than-air craft -- unless it would need to go somewhere with a lot of turbulence. Then, you want a heavier than aircraft. Having the wind speeds stated in terms of the local speed of sound would help. Remember, that will change with altitude.<br /><br />As for the type, if the turbulence problem can be avoided, I say that a rigid airship like the old Zeppelins would be ideal. Such a design would provide plenty of room for a uplink dish that would certainly be needed to communicate with the latest orbiter. If the turbulence areas are desired, I would suggest a fixed wing aircraft. (But I don't know how it would stay aloft at night.) <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[weeman]

We must first understand what mach numbers are. A basic equation can be used:<br /><br />M= V^o/V^s<br /><br />Where M is Mach, V^o is the object relative to the medium, and V^s is the speed of sound in the medium.<br /><br />The medium changes depending on altitude and pressure. For example, at higher elevations of several thousand feet, the speed of sound is about 660mph, this would be mach 1. However, at sea level, mach 1 would require a higher velocity than 660mph. <br /><br />http://www.xs4all.nl/~carlkop/jupork.html<br />This link states Jupiter's wind speeds depending on the distance from the very tip of the atmosphere to several miles down in the thick clouds. <br /><br />According to NASA's Ames Research Center, even at the cloud tops, wind speeds can reach 232mph. <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[sorehed]

Why would a fixed wing aircraft have trouble staying aloft at night?

 

[3488]

Would atmospheric composition have an affect on the speed of sound? Would Mach 1 at the 1 bar level in the atmospheres of Jupiter, Saturn, Uranus & Neptune with their Hydrogen rich atmospheres be the same as at sea level on Earth or the one bar level at Venus or Titan?<br /><br />Also the wind speeds at Jupiter surrounding the Great Red Spot & Red Spot Junior blow at about 640 KPH / 400 MPH.<br /><br />Saturn & Neptune have wind speeds exceeding 1,930 KPH / 1,200 MPH.<br /><br />Fixed wing aircraft would have no problem staying aloft at night. Jupiter, Saturn & Neptune have weather mostly driven by internal heat, rather than by sunlight!!! So night time flying would be no barrier.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[weeman]

It sounds to me like it is affected by atmospheric density. Being that the pressure is so intense as you go deeper into the gas giants, I would imagine that reaching mach 1 requires higher and higher speeds.<br /><br />That is my guess, I'm not completely knowledgable on this subject. <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[nexium]

My expertice is also limited, but the cloud tops of Jupiter's equator turn about thirty thousand miles per hour with respect to the distant stars. This not very significant except when you are leaving or arriving at Jupiter. I don't think we know the speed of the deeper atmosphere, but the light level is likely too low to get useful amounts of solar energy, so moving at other speeds than down wind will require lots of oxydent for fuel, for both airplanes and dirigibles. Jupiter does have random wind shears and gusts, which will likely stess airplanes, dirigibles, and humans if any. The smaller gas giants are thought to be calmer and their equators turn somewhat slower with respect to the distant stars. Neil

 

[why06]

For no particular reason. <br />May I ask why the sudden interest in gas giants? <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[willpittenger]

How would you power the craft's computer during the night? I would call that a priority. If you fail there, you could find the control surfaces doing odd things that they would not designed to do. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[willpittenger]

To borrow your user name: "Why not?" <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[sorehed]

The same way you power a craft's computer at night anywhere else. Engine-generated electrical power, apu's, batteries, power cells, etc. <img src="/images/icons/smile.gif" /><br />

 

[CalliArcale]

Folks curious about making unmanned electric fixed-wing aircraft fly at night should look up the Helios project, and in particular the Pathfinder aircraft. This was a flying wing powered by solar panels and batteries. It acheived the altitude record for powered flight by a conventional aircraft. (The only conventional aircraft to have acheived a higher altitude is the Space Shuttle, which sorta cheats. <img src="/images/icons/tongue.gif" /> ) The plan for the next phase was to replace the batteries with self-regenerating fuel cells, which can store more power in the same mass and could theoretically store enough power during the day to keep the vehicle going at night. This was all done with an eye to building "poor man's satellites" and possibly eventually aircraft to fly around other worlds.<br /><br />Unfortunately, the project came to an abrupt end when the aircraft was caught in crosswinds and crashed during testing in Hawaii. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[ianke]

Pathfinder ... 21.64km<br /><br />SR71 ... 25.93km<br /><br />x-15 ... 107.96km<br /><br />space Ship One ... 111.99km <br /><br />Pathfinder was quite an accomplishment though! <div class="Discussion_UserSignature"> </div>

 

[why06]

Poor Pathfinder. I've never actually heard of it though. <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[jschaef5]

The X-15 and SS1 aren't considered airplanes in some peoples books because they aren't air breathing, meaning rocket. <div class="Discussion_UserSignature"> </div>