ALEXANDER TSIARAS / SCIENCE PHOTO LIBRARY ALEXANDER TSIARAS / SCIENCE PHOTO LIBRARY
Laser beam entering the ion trap used in the American NIST-7 atomic clock. One disadvantage of current caesium atomic clocks is the very short observation time available as the caesium ions pass through the measurement chamber. The ion trap device uses complex electric and magnetic fields to contain ions within the space of 1 cubic cm. The laser is used to measure the oscillations of the ions between two energy levels. This oscillation provides the basis for measuring time with incredible accuracy. When complete, the NIST-7 clock is expected to be accurate to one billionth of a second per day (one second in three million years).
Model release not required. Property release not required.