Assertion: clock's time | /r/HasProperty | measured accurate
Facets:
value: to about 10−15 seconds
type: TEMPORAL
Source sentences:
text: With modern atomic time standards like TAI and UTC (see the section on Time Standards) and ultra-precise atomic clocks (see the section on Clocks), time can now be measured accurate to about 10−15 seconds, which corresponds to about 1 second error in approximately 30 million years.