Neil deGrasse Tyson’s Guide to Skywatching

From StarTalk.

What does AM or PM mean? Neil deGrasse Tyson walk comedian Chuck Nice through the different lines in the sky, their meanings, and how they are used in science. How do you use the coordinates for a specific star?

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.

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About StarTalk:
Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up!

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00:00 – Introduction
00:21 – Ante Meridian & Post Meridian
2:32 – The Solar Ecliptic
5:38 – How Does The Sky’s Coordinate System Factor in Precession?
10:03 – Impact on Zodiac Signs
13:00 – In Closing: The Finish Line