The world on Robinson projection. 15° graticule. Imagery is a derivative of NASA's Blue Marble summer month composite with oceans lightened to enhance legibility and contrast. Image created with the Geocart map projection software.
The world on Robinson projection. 15° graticule. Imagery is a derivative of NASA's Blue Marble summer month composite with oceans lightened to enhance legibility and contrast. Image created with the Geocart map projection software.

Things You Thought You Knew – The Geometric Universe

Strebe, CC BY-SA 3.0, via Wikimedia Commons
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About This Episode

What is the Sun’s ecliptic? Neil deGrasse Tyson and comedian Chuck Nice break down the things you thought you knew about spheres in the universe, navigating the sky, and taking spacecraft out of orbit.

Why is everything a sphere? What are the perks of being spherical? We explore why soap bubbles, cold pigeons, planets, and the sun are all round. Learn about asteroid Ceres’ upgrade to dwarf planet and how Saturn got its rings. We also get into disks: why are some object spheres and others disks?

What do AM and PM mean? Discover the sun’s path along the sky, how far it travels every day, and what Chuck thought AM and PM meant. We explore using right ascension and declination to create coordinates for stars. How does Earth’s precession get factored into this coordinate system? Learn about lines like the meridian, celestial equator, ecliptic, and the galactic equator. Plus, find out why the Zodiac signs are off an entire constellation.

Find out everything you need to know about deorbiting spacecraft and safely reentering our atmosphere. Learn about terminal velocity, escape velocity, and how aerobraking heat shields save fuel. We discuss issues with uncontrolled orbits and crashing into the Pacific Ocean. Plus, why did we let Cassini burn up in Saturn’s atmosphere? How are we going to get the ISS out of orbit? Neil also shares his ideas about the new space race and China’s space station.

Thanks to our Patrons Will Farmer, David Robertson, Andrii Snihyr, Michael de Boeve, Patricia A Elvin, Dade Bloomfield, Ahmed Dawod, Oenomaus Williamson, Marek Król, and Elizabeth Terveer  for supporting us this week.

NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free.

In This Episode

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