Episode #994

Hey gang, I really enjoyed episode 993 but I wanted to make a small correction to something that was said regarding piling up regolith on top of lunar habitats to protect from space radiation: ’…if you made a protective structure on a moon base with two to three feet of mooncrete on the outside, that would go a long way towards protecting you from radiation.’ It turns out that when incoming radiation enters shielding around a habitat, it can react with atoms in the shielding and produce secondary radiation. The counter-intuitive thing is that this secondary radiation can actually be more penetrating and harmful to the occupants of the habitat than the original primary radiation. So in order to effectively shield a habitat, you don’t just need sufficient shielding to stop incoming cosmic rays and what-not, but you also need enough shielding to shield against the spallation neutrons and other secondary nasties that the cosmic rays generate within the shielding. Some folks working on NASA’s In Situ Resource Utilization efforts estimated that the *break-even* point for piled up lunar regolith (where the effective dose within the habitat was the same as if there were no habitat shielding at all) could be as high as 7-9 METERS of regolith. After that, your shielding starts to actually be effective. GO LAVA TUBES! Thanks for everything you do, -Mouser

Item #1 Science
A recent analysis finds that the teeth of Komodo dragons are coated with iron to help maintain their strength and cutting edge. https://www.nature.com/articles/s41559-024-02477-7
Item #2 Science
An extensive study finds that for about half of the sites analyzed, the cost per ton of carbon removal is lower when just letting the land naturally regenerate than planting trees. https://www.nature.com/articles/s41558-024-02068-1
Item #3 Fiction
A recent study finds that the ability to recognize a previously heard piece of music significantly decreases with age in older adults. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0305969

‘One of my biggest pet peeves is when people use science that they don’t understand to try to justify their stupidity and hate.” ― Forrest Valkai