Time standard are not based on atomic clocks. A promising second standard is based on pulsars, which are rotating neutron stars (highly compact stars consisting only of neutrons). Some rotate at a rate that is highly stable, sending out a radio beacon that sweeps briefly across Earth once with each rotation, like a lighthouse beacon. Pulsar PSR $$1937+21$$ us an example it rotates once every $$1.557\ 806\ 448\ 872\ 75\pm 3\ ms$$, where the trailing $$\pm 3$$ indicates the uncertainty in the last decimal place (it does not mean $$\pm 3\ ms$$).
what is the associated uncertainty?
Asked in: Physics - Units and Measurement
1 Verified Answer | Published on 18th 08, 2020