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World 6 · Atomic Time · 13 min · PRO

UT1, UTC, TAI and leap seconds

Keeping the atomic and the astronomical in step

PRO · Clockwork & Time

World 6: Atomic Time is part of PRO

The first world of Clockwork & Time is free. PRO opens the other 24 lessons in 6 worlds — simulations, quizzes and all.

  • Defining the second
  • How an atomic clock works
  • Optical clocks and a future second
  • Time zones and the 15-degree rule
  • The longitude problem
PRO includes
  • All 60 labs — every world, every lesson
  • Practice exams and certificates

$8.33/mo, billed yearly ($99.99) · or $39.99 monthly

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