https://marspedia.org/index.php?title=Thorium&feed=atom&action=historyThorium - Revision history2024-03-28T21:31:01ZRevision history for this page on the wikiMediaWiki 1.34.2https://marspedia.org/index.php?title=Thorium&diff=139761&oldid=prevMichel Lamontagne at 19:08, 29 November 20222022-11-29T19:08:54Z<p></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|abundance=}}Thorium, ''[[Elements on Mars|Periodic table]] Th'', is present on [[Mars]], however, its surface concentration seems to be lower than on Earth.<ref name=":12">Map of Martian Thorium at Mid-Latitudes, JPL '' Map of Martian Thorium at Mid-Latitudes '', https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA04257, March 2003.</ref> Thorium can be used to produce fuel for [[Nuclear power|nuclear reactors]] on Mars, including [[LFTR|Liquid Fluoride Thorium Reactors]], [[Nuclear_thermal_propulsion|nuclear thermal propulsion]] and [[Ion_thruster#Pulsed_Fission_Fusion_.28PuFF.29|nuclear pulsed propulsion]]. </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|abundance=}}Thorium, ''[[Elements on Mars|Periodic table]] Th'', is present on [[Mars]], however, its surface concentration seems to be lower than on Earth.<ref name=":12">Map of Martian Thorium at Mid-Latitudes, JPL '' Map of Martian Thorium at Mid-Latitudes '', https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA04257, March 2003.</ref> Thorium can be used to produce fuel for [[Nuclear power|nuclear reactors]] on Mars, including [[LFTR|Liquid Fluoride Thorium Reactors]], [[Nuclear_thermal_propulsion|nuclear thermal propulsion]] and [[Ion_thruster#Pulsed_Fission_Fusion_.28PuFF.29|nuclear pulsed propulsion]]. </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Note that Thorium has a very long half life of 14 billion years, so the majority of the thorium that existed when the Earth formed is still here (<del class="diffchange diffchange-inline">Earth </del>is 4.5 billion years old). Thorium is not fissile, but it is fertile. In other words, thorium does not spontaneously fission, but with neutron bombardment, it will transform into fissionable U233.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Note that Thorium has a very long half life of 14 billion years, so the majority of the thorium that existed when the Earth <ins class="diffchange diffchange-inline">and Mars were </ins>formed is still here (<ins class="diffchange diffchange-inline">the planets are </ins>is 4.5 billion years old). Thorium is not fissile, but it is fertile. In other words, thorium does not spontaneously fission, but with neutron bombardment, it will transform into fissionable U233.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> Naturally concentrated deposits <del class="diffchange diffchange-inline">would </del>need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration from 500ppm to 25,000 ppm of Thorium.<ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> Naturally concentrated deposits <ins class="diffchange diffchange-inline">might </ins>need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td></tr>
</table>Michel Lamontagnehttps://marspedia.org/index.php?title=Thorium&diff=139718&oldid=prevRichardWSmith: Added a reference.2022-11-24T06:14:55Z<p>Added a reference.</p>
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 06:14, 24 November 2022</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l51" >Line 51:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* The next assumption that the thorium would burn up 100% is more suspect. Typical fission power plants burn only 0.5% of their fuel before it is 'spent' and sent to long term waste. However, current light water reactors were designed 70 years ago, and are WILDLY inefficient. They use SOLID fuel oxides, clad in zirconium alloy cladding. As the U235 fissions, the fuel elements swell and crack, releasing fission products (especially Xenon gas which is the worse neutron poison). The fuel cylinders swell which puts pressure on the Zr cladding. The zirconium cladding becomes brittle from neutron bombardment. So before they break, the fuel rod is removed (say after 17 months), and a new one is put in its place. The old fuel rods should be dissolved in acid, the fission products discarded, the 99.5% unburnt uranium recovered, converted back into a solid oxide and put back in a new fuel rod. But the fission products are wildly, dangerously radioactive, and this chemical processing is expensive (especially considering the radioactivity). Fresh fuel is so cheap, that it is more profitable to discard the used fuel rods, even tho more than 99% of the uranium has not fissioned.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* The next assumption that the thorium would burn up 100% is more suspect. Typical fission power plants burn only 0.5% of their fuel before it is 'spent' and sent to long term waste. However, current light water reactors were designed 70 years ago, and are WILDLY inefficient. They use SOLID fuel oxides, clad in zirconium alloy cladding. As the U235 fissions, the fuel elements swell and crack, releasing fission products (especially Xenon gas which is the worse neutron poison). The fuel cylinders swell which puts pressure on the Zr cladding. The zirconium cladding becomes brittle from neutron bombardment. So before they break, the fuel rod is removed (say after 17 months), and a new one is put in its place. The old fuel rods should be dissolved in acid, the fission products discarded, the 99.5% unburnt uranium recovered, converted back into a solid oxide and put back in a new fuel rod. But the fission products are wildly, dangerously radioactive, and this chemical processing is expensive (especially considering the radioactivity). Fresh fuel is so cheap, that it is more profitable to discard the used fuel rods, even tho more than 99% of the uranium has not fissioned.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>A LFTR burning thorium has a different philosophy. The unburnt fuel STAYS in the reactor until it 'burns'. The best place for these heavy nucleotides, is ''inside'' the reactor. Ideally, the only thing leaving the reactor is heat and fission products. The molten salt is a LIQUID so you can do chemical processes on it directly. Helium gas can be bubbled thru the working salt to pull out gases (such as xenon, radon, and tritium). Some elements will plate out on cool surfaces. (Tiny quantities of platinum, gold, iridium, etc. can be gained this way.) As for metals that will dissolve in the molten salt, they can be removed with some effort which requires many successive chemical steps. Originally it was intended to remove them constantly, but recently the idea is to let these products build up for a couple years, then remove the salt to a specialized plant to remove these wastes. While the wastes are in the reactor, they will take up a small amount of volume, reducing the reactor's efficiency slightly (trivial), but some are neutron poisons which lower the reactor efficiency (important). (This waste processing is the least developed part of LFTR. It has been designed on paper, but little practical work has been done.)</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>A LFTR burning thorium has a different philosophy. The unburnt fuel STAYS in the reactor until it 'burns'. The best place for these heavy nucleotides, is ''inside'' the reactor. Ideally, the only thing leaving the reactor is heat and fission products. The molten salt is a LIQUID so you can do chemical processes on it directly. Helium gas can be bubbled thru the working salt to pull out gases (such as xenon, radon, and tritium). Some elements will plate out on cool surfaces. (Tiny quantities of platinum, gold, iridium, etc. can be gained this way.) As for metals that will dissolve in the molten salt, they can be removed with some effort which requires many successive chemical steps. Originally it was intended to remove them constantly, but recently the idea is to let these products build up for a couple years, then remove the salt to a specialized plant to remove these wastes. While the wastes are in the reactor, they will take up a small amount of volume, reducing the reactor's efficiency slightly (trivial), but some are neutron poisons which lower the reactor efficiency (important). (This waste processing is the least developed part of LFTR. It has been designed on paper, but little practical work has been done.)<ins class="diffchange diffchange-inline"><ref>https://en.wikipedia.org/wiki/Liquid_fluoride_thorium_reactor#Removal_of_fission_products</ref></ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>However, if the reactor only burns up (say) 80% of its fuel rather than 100%, the cost of the fuel is still insignificant compared to value you can gain from the reactor. (You can also make the reactor (say) 25% bigger if the amount of energy is a concern.)</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>However, if the reactor only burns up (say) 80% of its fuel rather than 100%, the cost of the fuel is still insignificant compared to value you can gain from the reactor. (You can also make the reactor (say) 25% bigger if the amount of energy is a concern.)</div></td></tr>
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</table>RichardWSmithhttps://marspedia.org/index.php?title=Thorium&diff=139717&oldid=prevRichardWSmith: Added an additional problem with delaying processing the fission products.2022-11-24T06:11:00Z<p>Added an additional problem with delaying processing the fission products.</p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* The next assumption that the thorium would burn up 100% is more suspect. Typical fission power plants burn only 0.5% of their fuel before it is 'spent' and sent to long term waste. However, current light water reactors were designed 70 years ago, and are WILDLY inefficient. They use SOLID fuel oxides, clad in zirconium alloy cladding. As the U235 fissions, the fuel elements swell and crack, releasing fission products (especially Xenon gas which is the worse neutron poison). The fuel cylinders swell which puts pressure on the Zr cladding. The zirconium cladding becomes brittle from neutron bombardment. So before they break, the fuel rod is removed (say after 17 months), and a new one is put in its place. The old fuel rods should be dissolved in acid, the fission products discarded, the 99.5% unburnt uranium recovered, converted back into a solid oxide and put back in a new fuel rod. But the fission products are wildly, dangerously radioactive, and this chemical processing is expensive (especially considering the radioactivity). Fresh fuel is so cheap, that it is more profitable to discard the used fuel rods, even tho more than 99% of the uranium has not fissioned.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* The next assumption that the thorium would burn up 100% is more suspect. Typical fission power plants burn only 0.5% of their fuel before it is 'spent' and sent to long term waste. However, current light water reactors were designed 70 years ago, and are WILDLY inefficient. They use SOLID fuel oxides, clad in zirconium alloy cladding. As the U235 fissions, the fuel elements swell and crack, releasing fission products (especially Xenon gas which is the worse neutron poison). The fuel cylinders swell which puts pressure on the Zr cladding. The zirconium cladding becomes brittle from neutron bombardment. So before they break, the fuel rod is removed (say after 17 months), and a new one is put in its place. The old fuel rods should be dissolved in acid, the fission products discarded, the 99.5% unburnt uranium recovered, converted back into a solid oxide and put back in a new fuel rod. But the fission products are wildly, dangerously radioactive, and this chemical processing is expensive (especially considering the radioactivity). Fresh fuel is so cheap, that it is more profitable to discard the used fuel rods, even tho more than 99% of the uranium has not fissioned.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>A LFTR burning thorium has a different philosophy. The unburnt fuel STAYS in the reactor until it 'burns'. The best place for these heavy nucleotides, is ''inside'' the reactor. Ideally, the only thing leaving the reactor is heat and fission products. The molten salt is a LIQUID so you can do chemical processes on it directly. Helium gas can be bubbled thru the working salt to pull out gases (such as xenon, radon, and tritium). Some elements will plate out on cool surfaces. (Tiny quantities of platinum, gold, iridium, etc. can be gained this way.) As for metals that will dissolve in the molten salt, they can be removed with some effort which requires many successive chemical steps. Originally it was intended to remove them constantly, but recently the idea is to let these products build up for a couple years, then remove the salt to a specialized plant to remove these wastes. While the wastes are in the reactor, they will take up a small amount of volume, reducing the reactor's efficiency slightly. (This waste processing is the least developed part of LFTR. It has been designed on paper, but little practical work has been done.)</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>A LFTR burning thorium has a different philosophy. The unburnt fuel STAYS in the reactor until it 'burns'. The best place for these heavy nucleotides, is ''inside'' the reactor. Ideally, the only thing leaving the reactor is heat and fission products. The molten salt is a LIQUID so you can do chemical processes on it directly. Helium gas can be bubbled thru the working salt to pull out gases (such as xenon, radon, and tritium). Some elements will plate out on cool surfaces. (Tiny quantities of platinum, gold, iridium, etc. can be gained this way.) As for metals that will dissolve in the molten salt, they can be removed with some effort which requires many successive chemical steps. Originally it was intended to remove them constantly, but recently the idea is to let these products build up for a couple years, then remove the salt to a specialized plant to remove these wastes. While the wastes are in the reactor, they will take up a small amount of volume, reducing the reactor's efficiency slightly <ins class="diffchange diffchange-inline">(trivial), but some are neutron poisons which lower the reactor efficiency (important)</ins>. (This waste processing is the least developed part of LFTR. It has been designed on paper, but little practical work has been done.)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>However, if the reactor only burns up (say) 80% of its fuel rather than 100%, the cost of the fuel is still insignificant compared to value you can gain from the reactor. (You can also make the reactor (say) 25% bigger if the amount of energy is a concern.)</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>However, if the reactor only burns up (say) 80% of its fuel rather than 100%, the cost of the fuel is still insignificant compared to value you can gain from the reactor. (You can also make the reactor (say) 25% bigger if the amount of energy is a concern.)</div></td></tr>
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</table>RichardWSmithhttps://marspedia.org/index.php?title=Thorium&diff=139715&oldid=prevRichardWSmith: /* Concentration of thorium */ Added reference.2022-11-23T18:39:05Z<p><span dir="auto"><span class="autocomment">Concentration of thorium: </span> Added reference.</span></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration <del class="diffchange diffchange-inline">of </del>500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration <ins class="diffchange diffchange-inline">from </ins>500ppm <ins class="diffchange diffchange-inline">to 25,000 ppm </ins>of Thorium.<ins class="diffchange diffchange-inline"><ref>https://aip.scitation.org/doi/pdf/10.1063/1.4972913</ref> </ins> Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium.<ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td></tr>
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</table>RichardWSmithhttps://marspedia.org/index.php?title=Thorium&diff=139714&oldid=prevRichardWSmith: /* Concentration of thorium */ Added reference.2022-11-23T18:32:21Z<p><span dir="auto"><span class="autocomment">Concentration of thorium: </span> Added reference.</span></p>
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 18:32, 23 November 2022</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> mines could be utilized, which typically produce a waste stream enriched in thorium.<ins class="diffchange diffchange-inline"><ref>https://trace.tennessee.edu/cgi/viewcontent.cgi?article=3397&context=utk_chanhonoproj</ref> </ins>Other mines occasionally produce tailings enriched in thorium.<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td></tr>
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</table>RichardWSmithhttps://marspedia.org/index.php?title=Thorium&diff=139713&oldid=prevRichardWSmith: Made sentence more accurate.2022-11-23T18:28:04Z<p>Made sentence more accurate.</p>
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 18:28, 23 November 2022</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> <del class="diffchange diffchange-inline">or other</del><ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> <del class="diffchange diffchange-inline">mines could be utilized, which typically produce a waste stream enriched in thorium. </del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> <ins class="diffchange diffchange-inline">mines could be utilized, which typically produce a waste stream enriched in thorium. Other mines occasionally produce tailings enriched in thorium.</ins><ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td></tr>
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</table>RichardWSmithhttps://marspedia.org/index.php?title=Thorium&diff=139712&oldid=prevRichardWSmith: formatting2022-11-23T18:26:36Z<p>formatting</p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue<sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> or other<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue<ins class="diffchange diffchange-inline">></ins><sup>Citation Needed</sup></span> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> or other<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td></tr>
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</table>RichardWSmithhttps://marspedia.org/index.php?title=Thorium&diff=139711&oldid=prevRichardWSmith: formatting2022-11-23T18:25:33Z<p>formatting</p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue<del class="diffchange diffchange-inline">;</span></del><sup>Citation Needed</sup> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> or other<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<span style="color: blue<sup>Citation Needed</sup<ins class="diffchange diffchange-inline">></span</ins>> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> or other<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td></tr>
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</table>RichardWSmithhttps://marspedia.org/index.php?title=Thorium&diff=139710&oldid=prevRichardWSmith: still farting around with formatting.2022-11-23T18:24:50Z<p>still farting around with formatting.</p>
<table class="diff diff-contentalign-left" data-mw="interface">
<col class="diff-marker" />
<col class="diff-content" />
<col class="diff-marker" />
<col class="diff-content" />
<tr class="diff-title" lang="en">
<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 18:24, 23 November 2022</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l9" >Line 9:</td>
<td colspan="2" class="diff-lineno">Line 9:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<sup>Citation Needed</sup> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> or other<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<ins class="diffchange diffchange-inline"><span style="color: blue;</span></ins><sup>Citation Needed</sup> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> or other<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td></tr>
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</table>RichardWSmithhttps://marspedia.org/index.php?title=Thorium&diff=139709&oldid=prevRichardWSmith: trying to fix formatting.2022-11-23T18:12:35Z<p>trying to fix formatting.</p>
<table class="diff diff-contentalign-left" data-mw="interface">
<col class="diff-marker" />
<col class="diff-content" />
<col class="diff-marker" />
<col class="diff-content" />
<tr class="diff-title" lang="en">
<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 18:12, 23 November 2022</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l9" >Line 9:</td>
<td colspan="2" class="diff-lineno">Line 9:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Concentration of thorium==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<del class="diffchange diffchange-inline">"citationNeeded" </del> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> or other<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The average surface concentration is 0,6 ppm, or about ten times lower than Earth' average abundance of 6 ppm, with some high concentration areas of about 1 ppm <ref>https://en.wikipedia.org/wiki/Occurrence_of_thorium</ref>. See map. Martian basalts may have concentrations of 5 ppm(), similar to the basalts of Earth. Monazite (a phosphate mineral that also includes rare Earth elements) mines on Earth can have a concentration of 500ppm of Thorium. Naturally concentrated deposits would need to be found to make the use of Thorium economical on Mars in the long term.<ins class="diffchange diffchange-inline"><sup>Citation Needed</sup> </ins> Alternately the tailings of [[Rare Earths|rare earth elements]] mines<ref>https://www.youtube.com/watch?v=lxwF93wnRQo</ref> or other<ref>https://www.epa.gov/radiation/tenorm-copper-mining-and-production-wastes</ref> mines could be utilized, which typically produce a waste stream enriched in thorium. </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This page: [[Radioactive Rarity on Mars]] discusses the apparent rarity of radioactive elements on Mars.</div></td></tr>
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</table>RichardWSmith