1. Meet the zeptosecond, the shortest unit of time ever measured  Live Science
  2. World Record of Smallest Time Measurement Broken | IE  Interesting Engineering
  3. View Full Coverage on Google News
Scientists have measured the shortest unit of time ever, the time it takes for a particle of light to cross a hydrogen molecule.

Meet the zeptosecond, the shortest unit of time ever measured | Live Science

The shortest timespan that has ever been measured amounts to about 247 zeptoseconds (1 zs = 10^-21 seconds)The shortest timespan that has ever been measured amounts to about 247 zeptoseconds (1 zs = 10^-21 seconds)

World Record of Smallest Time Measurement Broken | IE