If you were to

[skippystars]

Land on any of the so called "gas giants" would you ever be able to stand on it? Neptune and Uranus as well as Jupiter and Saturn for example each have mantles. Isn't there a crust? <br /><br />Could we stand on these places?<br />Thanks all<br /><br />SK

 

[nexium]

No, no and no.<br />If our present theories are mostly wrong; Maybe.<br />All 4 gas giants are thought to have atmospheres thousands of miles thick. Below that, the temperature is thought to be thousands of degrees, so the "atmosphere" is thought to be plasma = the atomic nuclii are striped of one of more of their electrons, so that most are ions rather than atoms. At these temperatures, our space suit would quickly melt, sublinate and/or boil away. Still deeper in the atmosphere, Jupiter is thought to have licquid metalic hydrogen, which a robot made of unobtainium (not available and likely never will be available) might float on. We might call this a crust. I have no idea why we would think a gas giant has a mantel. If it does, it would be almost nothing like the mantel of Earth which is also unvarified theory. edit: I changed this post to liquid metalic hydrogen.<br />We can possibly have colonies near the cloud tops of the gas giant planets and Venus, supported by balloons. Neil

 

[skippystars]

Solid hydrogen would require a very very cold temperature right? Isn't the temperature in space where astronauts do their daily activities in, colder then that region in Jupiter that you were talking about? <br /><br />If so why couldn't an astronaut (excluding all other variables) stand on cold hydrogen?<br /><br />Or is it colder at the location of Jupiter solid hydrogen <br /><br />SK

 

[skippystars]

anyone?<br /><br />This is "Ask the astronomer" right?<br /><br />let me check..

 

[drwayne]

Its also the holiday season, so many regulars are out.<br /><br /><img src="/images/icons/smile.gif" /><br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[bobw]

I don't know about solid hydrogen but I remember reading when scientists first made liquid metallic hydrogen. There was a lot of talk about it being in Jupiter and Saturn. I googled up a couple of quick links about metallic hydrogen since your original question was about gas giants. The first link suggests that there is no solid core in Jupiter but that it is liquid metallic hydrogen; there are some picture diagrams about 2/3 of the way down the page. <br /><br /><font color="yellow">HYDROGEN is the simplest and most abundant of elements. Composed of one proton and one electron, it makes up 90% of our universe (by number of atoms). On Earth, hydrogen is commonly found as a diatomic molecular gas. But on Jupiter, where interior pressure is millions of times greater than that at our planet's surface, the hydrogen molecule is theorized to exist as a superhot liquid metal.<br /><br />Jupiter, which is almost 90% hydrogen, is not the only planet rich in metallic hydrogen. Hot metallic hydrogen is believed to make up the interior of Saturn and may be present in other large planets discovered recently outside our solar system.</font><br /><br />The Q&A at the end of the page talks about some stuff that seems pretty Sci-Fi right now. Nobody knows how to do it or if it can be done, but you never know what the future might bring.<br /><br /><font color="yellow">Metallic solid hydrogen has been predicted to be a room-temperature superconductor, which would result in substantial energy conservation nationwide.</font><br /><br />http://www-pat.llnl.gov/H_Div/GG/Nellis.html<br />http://www.aip.org/pnu/1996/split/pnu263-1.htm <div class="Discussion_UserSignature"> </div>

 

[MeteorWayne]

Besides THE astronomer will be a bit busy on Christmas Eve, if you know what I mean <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[nexium]

I appologize for mentioning solid hydrogen which is typically colder than minus 258 degrees c. The cloud tops of the gas giant planets are warmer and the interiors are thought to be much hotter than frozen hydrogen. Deep in the atmosphere the pressure is thought be much higher than the bottom of deepest ocean of Earth. As usual bobw gave a good answer. Neil

 

[skippystars]

Thank you for the follow up all!

 

[alokmohan]

Where we stand then,gas giant or no gas giant?

 

[SpeedFreek]

I think we agree that wherever we stand, it is NOT going to be on a gas giant! <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>