November 2018 Global Tremor Could have been Due to a Galactic Gravity Wave

On November 11, 2018 seismographs all over the world picked up a prolonged global tremor that has confounded seismologists. It was a slow monochromatic oscillation of the planet that had a period of about 17 seconds and a magnitude of about 5 Richtor (see upper two oscillograms). When the data was processed to filter out the main oscillation, low amplitude P-waves and S-waves were also seen which had strengths of about 1/10 that of the main tremor. More