The Strange Reason a Compass Points North… (It's Not Magnetism)

Hey guys! We’re now live on Spotify🎧 Listen here: https://open.spotify.com/show/3qYsIDs... There is no magnet inside the Earth. Its iron core is thousands of degrees too hot to hold any magnetism, yet the needle on your shelf still settles toward the north. That north wanders across the Arctic, and long ago it pointed south. So what is a compass actually pointing at? Tonight we follow one small needle all the way down: a silk thread in old China, a flag on a frozen Arctic shore, faint earthquake waves, and a machine in Latvia that did something nobody had managed before. Get cozy and let this slow walk through the physics of the compass keep you company tonight. Subscribe to Lights Out Physics if you enjoy the long way around the universe. CHAPTERS 0:00 Introduction 1:26 The needle that settles 12:29 The great magnet 22:50 The north that wanders 34:10 Too hot to be a magnet 44:26 What the earthquakes saw 54:31 The wire and the needle 1:05:07 The machine that makes itself 1:16:14 The engine room 1:27:04 The field that flips 1:38:23 Building a planet's heart 1:48:30 The shield and the weak spot 1:59:02 The field that nearly died 2:09:13 What the needle points at SOURCES Swarm probes weakening of Earth's magnetic field (ESA) — https://www.esa.int/Applications/Obse... World Magnetic Model Out-of-Cycle Release (CIRES) — https://cires.colorado.edu/news/world... Wandering of the Geomagnetic Poles (NOAA NCEI) — https://www.ncei.noaa.gov/products/wa... Airport Runways Shift With The Magnetic North Pole (NPR) — https://www.npr.org/sections/talk/201... July 1820: Oersted & Electromagnetism (APS News) — https://aps.org/apsnews/2008/07/1820-... The Lodestone (NASA Goddard) — https://pwg.gsfc.nasa.gov/earthmag/lo... Fast torsional waves and strong magnetic field within the Earth's core (Nature) — https://www.nature.com/articles/natur... History and results of the Riga dynamo experiments (arXiv) — https://arxiv.org/abs/0807.0305 Computer simulations reveal workings of the dynamo behind Earth's magnetic field (UC Santa Cruz) — https://www1.ucsc.edu/news_events/pre... An extremely brief reversal of the geomagnetic field (GFZ Potsdam) — https://www.gfz.de/en/press/news/deta... Earth's inner core is young at heart (Physics Today) — https://physicstoday.aip.org/news/ear... Earth's magnetic shield is much older than previously thought (ScienceDaily) — https://www.sciencedaily.com/releases... Mars Global Surveyor Shows Magnetic Field Protects Atmosphere (UC Berkeley) — https://ucolick.org/news/2000/00-12-1... — Disclaimer: Lights Out Physics is an education and relaxation channel. Factual material is based on peer-reviewed research and official scientific bodies; any speculation, fringe theory, or personal analysis is identified as such when it appears. This is not a news channel. Viewer discretion advised. #EarthsMagneticField #MagneticNorthPole