<story><title>Potential ozone depletion from satellite demise during atmospheric reentry</title><url>https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GL109280</url></story><parent_chain><item><author>adrian_b</author><text>The Japanese have already been concerned by this problem for a few years.&lt;p&gt;Their solution has been to develop satellites made mostly of wood, which will burn completely upon reentry.&lt;p&gt;The first such wooden satellite is planned to be launched in September. It is intended mainly for collecting data about the behavior of wood in the outer space, e.g. on wood expansion, contraction and degradation, along with internal temperature and electronic equipment performance.&lt;p&gt;An alternative to wood would be the use of synthetic polymers, but those are typically more sensitive to radiation, so more research would be needed for finding a suitable plastic and appropriate additives to decrease the radiation sensitivity.&lt;p&gt;Wood or plastic would not be suitable for ships hosting humans, because they are not hermetic, but they may be an acceptable choice for satellites with a short lifetime and with much more relaxed constraints for the composition and pressure of the internal atmosphere (which may not be needed at all, e.g. when the internally produced heat reaches the external radiant cooling surfaces through solid paths or through pipes with circulant liquid).</text></item></parent_chain><comment><author>tivert</author><text>&amp;gt; Their solution has been to develop satellites made mostly of wood, which will burn completely upon reentry.&lt;p&gt;I like how the Google image search for &amp;quot;japan wooden satellite&amp;quot; (&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.google.com&amp;#x2F;search?q=japan+wooden+satellite&amp;amp;udm=2&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.google.com&amp;#x2F;search?q=japan+wooden+satellite&amp;amp;udm=2&lt;/a&gt;) is gummed up with garbage AI generated images of satellites with wooden solar panels. This wooden Borg cube with off-kilter panels is my favorite: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;indianspacetechnology.com&amp;#x2F;wooden-satellite-lignosat-spacepollution&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;indianspacetechnology.com&amp;#x2F;wooden-satellite-lignosat-...&lt;/a&gt;.  This one is also great: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.universetoday.com&amp;#x2F;161473&amp;#x2F;building-a-satellite-out-of-wood-use-magnolia&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.universetoday.com&amp;#x2F;161473&amp;#x2F;building-a-satellite-ou...&lt;/a&gt;. I guess the satellite went back in time to the Cretaceous period, where North America had an inland sea?&lt;p&gt;The future is looking bright, guys!</text></comment>
<story><title>Potential ozone depletion from satellite demise during atmospheric reentry</title><url>https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GL109280</url></story><parent_chain><item><author>adrian_b</author><text>The Japanese have already been concerned by this problem for a few years.&lt;p&gt;Their solution has been to develop satellites made mostly of wood, which will burn completely upon reentry.&lt;p&gt;The first such wooden satellite is planned to be launched in September. It is intended mainly for collecting data about the behavior of wood in the outer space, e.g. on wood expansion, contraction and degradation, along with internal temperature and electronic equipment performance.&lt;p&gt;An alternative to wood would be the use of synthetic polymers, but those are typically more sensitive to radiation, so more research would be needed for finding a suitable plastic and appropriate additives to decrease the radiation sensitivity.&lt;p&gt;Wood or plastic would not be suitable for ships hosting humans, because they are not hermetic, but they may be an acceptable choice for satellites with a short lifetime and with much more relaxed constraints for the composition and pressure of the internal atmosphere (which may not be needed at all, e.g. when the internally produced heat reaches the external radiant cooling surfaces through solid paths or through pipes with circulant liquid).</text></item></parent_chain><comment><author>observationist</author><text>Nanocrystalline cellulose (NCC) could be a great constituent component of a composite material. Not only would it burn, but anything that doesn&amp;#x27;t burn and makes  it to the surface is biodegradable; there&amp;#x27;s lots of stuff that eats cellulose. NCC can be formed into highly strong and rigid structural pieces, or combined with carbon fiber, fiberglass, hemp, or other fibers to create ultra strong and durable composite material.&lt;p&gt;&lt;pre&gt;&lt;code&gt;   high mechanical strength, with a tensile modulus of approximately 150 GPa and a modulus of elasticity ranging from 18 to 50 GPa. CNCs also exhibit excellent thermal stability, undergoing gradual thermal transitions and decomposition between 150 °C and 600 °C&lt;/code&gt;&lt;/pre&gt;</text></comment>