People in Jupiter's Radiation Belt

[willpittenger]

In the book and movies for Arthur C. Clarke's <i>2001</i>/<i>2010</i>, we see the Discovery and Lenonov visiting Io and the flux tube. I assume that a simple shielded emergency room would not be enough to protect the crews there. How would we protect entire pressurized areas from the radiation? <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>

 

[MeteorWayne]

I don't think this belongs in missions and launches. Look for it elsewhere soon <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>

 

[yevaud]

Moving this thread to ATA. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[3488]

That is very true.<br /><br />At Io, the radiation is four MEGARADS per day. The lethal dose for a human is less than <br />one KILORAD a day. At Io some 4,000 times the lethal dose for humans.<br /><br />Even radiation hardened electronics hjave a hard time. The radiation picks apart the <br />'lattice' structure within electrical components, thus rendering them useless<br />(destroys the conductive 'pathways').<br /><br />This was what almost killed Pioneer 10.<br /><br />The Galileo spacecraft had a malfunctioning diode in the digital tape recorder just after the <br />I33 / A34 encounters. It was fixed by sending extra power from the RTG to it & it <br />sort of welded itself, restoring the 'lattice'.<br /><br />As crazyeddie says, without immense shielding & / or magntic fields, the craft would be<br />knackered within a short time frame.<br /><br />I am trying to get an Io mission approved, but to be honest, it will probably<br />fail, due to the reasons above.<br /><br /><br />If a four Megarad dose can do that to hardware, think of what it would do to your DNA??????<br /><br />H2Ouniverse was kind enough to tip me off about a potential orbital Ganymede mission,<br />so that could be my Phoenix.<br /><br />At Ganymede, whilst there is some elevated radiation, it is only a tiny fraction as at Io or even <br />Europa. So normal electronics would probably be O.K there.<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>

 

[willpittenger]

Could you explain your reasoning behind the move? I put it into M&L because it involved a manned mission to Jupiter. <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>

 

[yevaud]

Well, it's not so much about a mission, as about the physics of a mission, such as it were. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[willpittenger]

Well, that would imply that the discussion would be only about the local environment. However, the question involved how to design the spacecraft. <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>

 

[alokmohan]

But manned mission to Jupiter is thrilling idea.

 

[willpittenger]

Unfortunately, the choice of forum has not helped this thread any. The people here know about the environment, but not necessarily how to survive in that environment. <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>

 

[dragon04]

<font color="yellow">Unfortunately, the choice of forum has not helped this thread any. The people here know about the environment, but not necessarily how to survive in that environment.</font><br /><br /><b>How</b> to survive the environment is simple. Being able to <b>do</b> so is beyond feasible capabilities at the moment. <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[docm]

<font color="yellow">At Io, the radiation is four MEGARADS per day. The lethal dose for a human is less than one KILORAD a day.</font><br /><br />The SI unit is the Gray (Gy) which is equal to 100 R.<br /><br />Acute Radiation Syndrome can occur anywhere from less than 1 Gy (100 R) on up, but as noted it's almost always fatal at doses greater than 10 Gy (1000 R).<br /><br />4 megaR/day 'eh? Let's see how much shielding that would require.<br /><br />Most calculations use R/hr, so it's ~166666.7 R/hr. <br /><br />Designs like Bigelows use water jackets so we'll start there and then move on to aluminum and lead. <br /><br />Electromagnetic shielding will only work on charged particles and not gamma, neutrons etc. They need barriers or reflectors (beryllium for neutrons).<br /><br />I did the calculations to achieve a dose of 0 R/hr from a Cobalt 60 (2.824 MeV) gamma source. Particles <i>should</i> require much less. From there it's a calculation of how much human risk is acceptable and what your hardware can tolerate.<br /><br />Required shielding for 0 R:<br /><br /><b>Water:</b> 4759.76 inches<br /><br /><b>Aluminum:</b> 2027.59 inches<br /><br /><b>Lead:</b> 460.66 inches<br /><br />Better start by building a Jupiter XX booster <img src="/images/icons/tongue.gif" /> <br /><br />That said there is a polymer shielding material called "Demron" that's supposed to be as effective as lead for X-rays & low gammas but much, much lighter. <div class="Discussion_UserSignature"> </div>

 

[willpittenger]

What about depleted uranium or tungsten. The army likes them because of their sheer density. Short of the stuff that make up a neutron star, you won't find many materials that are denser. <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>

 

[docm]

DU is 70% denser than lead, 19,050 kg/m³, so make that booster a Jupiter XXV <img src="/images/icons/tongue.gif" /><br /><br />Even so Tungsten is close for Co60;<br /><br />Tungsten = 281.65 inches<br /><br />Uranium = 250.82 inches <br /><br /> <div class="Discussion_UserSignature"> </div>

 

[willpittenger]

No mention of that packed neutron material? (I don't know if we should call it "Neutronium" like they did in Star Trek or not.)<br /><br />Seriously, do the denser options result in a lower mass? <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>

 

[docm]

"Neutronium" was originally a sci-fi term for an all-neutron "metal", though some now use it as a synonym for neutron degenerate matter; a mixture of neutron, proton and electron gases at extremely high densities. Trust me, you wouldn't want to be anywhere near neutron degenerate matter much less use it as a "shield". <br /><br />Denser means heavier for a given volume, so uranium is heavier than an equal volume of lead; lead than tungsten; tungsten than aluminum and so on. <br /><br />If one can get close to equivalent shielding with a less dense material, or mix of materials, that's generally the way to go but you have to tailor it to the type of radiation(s) at hand. <br /><br />Example: beryllium reflects neutrons, but it's virtually transparent to X-rays. <br /><br />You often see composite shielding, and it's not always the heavy materials that get chosen. Examples are layered lithium hydride-tungsten, boron carbide-tungsten and lithium hydride-beryllium which have been looked at for shielding neutrons and gamma in spaceship reactors.<br /> <div class="Discussion_UserSignature"> </div>

 

[3488]

Hi alokmohan.<br /><br />It is a thrilling idea. Could not agree with you more.<br /><br />I fear that human presence within the inner Jovian system as portrayed in 2010<br />Odyssey Two, will not happen for a very looooooog time indeed. I dso think it will<br />be possible eventually, once we know more about high radiation environments & can<br />develop materials / magnetic fields accordingly.<br /><br />Having said that, I cannot see why a human presense at Ganymede & Callisto would<br />be out of bounds. Human exploration of these two though, would be worth the effort alone.<br /><br />Smaller radiation uncrewed probes could be launched inwards, from the manned "mothership'<br />much like the Apollo subsats, but fully instrumented .<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>

 

[willpittenger]

The idea was that the denser material would require less volume for the same amount of protection. Hence, would that result in less mass? <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]

So what would the time delay be for signals going from Jovian moon to moon? (All combinations involving only the Galilean moons please.)<br /><br />Edit: The old wording was ridiculously broad. <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>

 

[docm]

<font color="yellow">The idea was that the denser material would require less volume for the same amount of protection. Hence, would that result in less mass?</font><br /><br />That's not at all a linear relationship as the Uranium and Tungsten numbers above show, in fact some polymers are terrific shields for some kinds of radiation. Just depends on what you're shielding against. High hydrogen content aliphatic* polymers work well vs. cosmic rays for example.<br /><br />*organic compounds in which the carbon atoms are linked in open chains. <div class="Discussion_UserSignature"> </div>

 

[kelvinzero]

http://en.wikipedia.org/wiki/Callisto_%28moon%29<br /><blockquote><font class="small">In reply to:</font><hr /><p><br />The remoteness of Callisto from Jupiter also means that charged particles flux from the planetary magnetosphere at its surface is relatively low, about 300 times lower than that at Europa. The charged particle irradiation has had a relatively minor effect on the callistoan surface.<br /><p><hr /></p></p></blockquote>

 

[3488]

Thanks KelvinZero.<br /><br />I was just researching this myself to provide an answer.<br /><br />Yes you are correct. At Callisto, it is 0.3% as at Europa, which in turn is 15% that of Io.<br /><br />4 Megarads / 40,000 Grays @ Io. 600 Kilorads / 6,000 Grays @ Europa. <br /><br />Only 4 Kilorads / 40 Grays @ Ganymede & <br />only 2 Kilorads / 20 Grays @ Callisto. Whilst still above the lethal dose for humans, <br />with normal shielding, sensible procedures, etc, no real problem. <br /><br />It is not too dangerous at Ganymede either, although more caution will be required there.<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>

 

[willpittenger]

I realized I goofed on the wording of the post I am replying to. I made the request seem impossible and irrelevant. Sorry. <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>

 

[thalion]

I have to admit, as much as I love the books, I've always been a bit surprised that Clarke never really addressed that problem. As someone else already wrote, factoring it into the novel would've ruined the drama.<br /><br />

 

[willpittenger]

I should point out that Clarke originally set 2001 in the Saturn system. I assume the radiation is not as bad there. <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>

 

[3488]

Thats true willpittenger.<br /><br />Saturn has a huge magnetosphere, second only to Jupiter's in size & strength.<br /><br />However, Saturns greater distance from the Sun, & the rings absorb the charged particals,<br />means that Saturn has very little in the way of radiation belts.<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>