>>12967150>>12967156Putting together seismograph readings from around the planet measuring the P (compression) waves and S (Traverse) waves from known earthquakes and their epicenters shows the different layers
S waves can't travel through a liquid, and seismographs on the opposite side of the earthquake don't detect its S waves, indicating a liquid core
P waves can travel through them but refract in different materials in different states, the P waves refract in different angles picked up in those seismographs
