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Thing You Thought You Knew – Red Hot, Blue Hot

40 min episode · 2 min read

Episode

40 min

Read time

2 min

Topics

Productivity, Psychology & Behavior, Philosophy & Wisdom

AI-Generated Summary

Key Takeaways

  • Molecular scale comprehension: A single cup of water contains more H2O molecules than there are cups of water in all Earth's oceans, meaning every glass you drink contains roughly 100 molecules that passed through the kidneys of historical figures like Abraham Lincoln or Genghis Khan due to molecular redistribution over time.
  • Avogadro's number application: One mole of carbon weighs 12 grams (one-third of an ounce) yet contains 6.022 times 10 to the 23rd power molecules, a quantity 100 times larger than the number of stars in the observable universe, demonstrating why molecules remain invisible despite their ubiquitous presence in matter.
  • Color temperature physics: Objects glowing at 1,500 degrees Celsius emit red light, while objects at 20,000-30,000 degrees emit blue light, making blue the hottest visible color. Photographers incorrectly label 6,000-degree lamps as cool daylight and 3,000-degree lamps as warm, inverting the actual temperature scale for artistic purposes.
  • Biological food preservation: Chemical and biological processes double their rate every 10 degrees Celsius, which explains why refrigeration extends food life. Ultra-pasteurized milk lasts significantly longer than regular pasteurized milk because irradiation removes more initial microbes, delaying the doubling time required to reach spoilage threshold concentrations.
  • Quantum food degradation: Even vacuum-sealed, irradiated food eventually degrades through quantum tunneling, where molecules transition to lower energy states by passing through energy barriers. This chemical decomposition changes food texture over years, making long-term space mission food storage require consideration beyond simple microbial contamination prevention.

What It Covers

Neil deGrasse Tyson explains three counterintuitive scientific concepts: the microscopic scale of molecules using Avogadro's number and water molecule calculations, the physics of color temperature where blue objects are hotter than red ones, and how food degrades through both biological contamination and quantum mechanical processes called tunneling.

Key Questions Answered

  • Molecular scale comprehension: A single cup of water contains more H2O molecules than there are cups of water in all Earth's oceans, meaning every glass you drink contains roughly 100 molecules that passed through the kidneys of historical figures like Abraham Lincoln or Genghis Khan due to molecular redistribution over time.
  • Avogadro's number application: One mole of carbon weighs 12 grams (one-third of an ounce) yet contains 6.022 times 10 to the 23rd power molecules, a quantity 100 times larger than the number of stars in the observable universe, demonstrating why molecules remain invisible despite their ubiquitous presence in matter.
  • Color temperature physics: Objects glowing at 1,500 degrees Celsius emit red light, while objects at 20,000-30,000 degrees emit blue light, making blue the hottest visible color. Photographers incorrectly label 6,000-degree lamps as cool daylight and 3,000-degree lamps as warm, inverting the actual temperature scale for artistic purposes.
  • Biological food preservation: Chemical and biological processes double their rate every 10 degrees Celsius, which explains why refrigeration extends food life. Ultra-pasteurized milk lasts significantly longer than regular pasteurized milk because irradiation removes more initial microbes, delaying the doubling time required to reach spoilage threshold concentrations.
  • Quantum food degradation: Even vacuum-sealed, irradiated food eventually degrades through quantum tunneling, where molecules transition to lower energy states by passing through energy barriers. This chemical decomposition changes food texture over years, making long-term space mission food storage require consideration beyond simple microbial contamination prevention.

Notable Moment

Tyson reveals that photographers request higher temperature lamps (6,000 degrees) to create cooler-looking scenes and lower temperature lamps (3,000 degrees) for warmer scenes, creating an absurd inversion where professionals numerically specify temperatures while contradicting actual physics, frustrating astrophysicists who understand blue indicates extreme heat in the universe.

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Episode Transcript

Hey, StarTalkians. We've got yet another Things You Thought You Knew episode. We're talking about small molecules, the temperature of light, and food gone bad. Check it out. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. Do you have any idea how small molecules are? Well, seeing, as I can't see them, I'm gonna say I do not. Right. And even if you did say you knew, I would say you didn't know. I'm just pulling rank here. I'm just saying molecules I mean, think about it. Our understanding of the existence of atoms did not even come into age until the twentieth century. Atoms were were still a hypothesis, alright, that there'd be this sort of smallest unit of a material called the atom. By the way, the word atom from the Greek means indivisible. So they imagined that there was some indivisible minimal part of a thing. But, of course, we break out bust atoms all the time. So, no, they're not indivisible, but we kept the term. Right. We kept the term atom to describe the electrons, protons, neutrons, the classical particles you learn about in in high school chemistry and maybe physics. So, so molecules are I I could give an example. Okay? And and this is my favorite example of them all. So I ask you think about how much water there is in the world, in all the oceans. Okay. And if you go in the middle of the ocean, it's miles deep. Okay? The Titanic was, like, three and a half mile. I forgot the exact number. Multiple miles below Earth's surface. Okay? That's a lot of water. It's a lot of water. And what is the water molecule? H two l. H two l. Okay. So two hydrogen, one oxygen, h two l. So it just salts and dissolved salts and fish poop and stuff like that, but by it's basically h two o all over the world. Alright. I love that you threw in the fish poop. I'm so proud of you. Thank you. That's the juvenile part. The the eight year olds will wanna know that. Yes. Exactly. There's also fish poop Right. In in the ocean. So where else does it go? Right? And just to recite the title of a book they may have grown up on, everything poops. Yeah. And it shows it's just a story. It's for little kids. I know. Because they poop and they know they poop and they're fascinated by it. And it's just an account that everybody poops. And all the fish poop in the ocean. Okay? They don't go onto land to poop. Yeah. I I read that book to my daughter. She thought it was crappy. I couldn't help it. Alright. So they don't have outhouses on the land. Right? Right. All in there. That would be amazing, though. They poop poop in situ. Would that be oh, god. You …

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