Activity Mark Sean de Cantual posted an update 6 years, 4 months ago Soundwave propogating? Thoughts? https://www.unilad.co.uk/science/nasa-cameras-capture-soundwaves-from-mystery-spacecraft-hurtling-across-earth/?source=facebook&fbclid=IwAR2wKZuCdK0Oq1tAfPLfkStmxQ9bDve4e_9OHOPGhP36pZHOqR6B-Nn8UBs
