In two cases, the arrival times and forms of seismic waves at nine far-flung stations pointed to linear bursts of energy. The ruptures ripped through the planet at hundreds of kilometres per second rather than fracturing only near the surface, as typical earthquakes do.
One event occurred on 22 October 1993, when, according to the researchers, something entered the Earth off Antarctica and left it south of India 0.73 of a second later.
The other occurred on 24 November 1993, when an object entered south of Australia and exited the Earth near Antarctica 0.15 of a second later.
Remember Lance, I said I thought I felt something.