Key Takeaways
- Xcel Energy preemptively shut off power to protect areas of Colorado from extreme fire danger due to hurricane force winds.
- The power outage briefly affected the NIST Internet Time Service facility in Boulder, causing a 4 microsecond drift in timekeeping.
- The NIST F-4 atomic clock uses cesium atoms to measure the exact length of a second and is used for various applications, including GPS systems and scientific research.
- The clock’s accuracy is maintained by a network of clocks and servers in different locations, ensuring minimal impact from the power outage.
- The system is not at risk, and redundancies are in place to ensure uninterrupted service.
Introduction to the NIST Internet Time Service
The National Institute of Standards and Technology (NIST) Internet Time Service facility in Boulder, Colorado, is a critical component of the global timekeeping infrastructure. The facility is home to the NIST F-4 atomic clock, which uses cesium atoms to measure the exact length of a second. This clock is used for a wide range of applications, including GPS systems, data centers, scientific research, telecommunications, power generation, and other systems that require ultra-precise timekeeping. The NIST F-4 clock is based on a "fountain" design, which represents the gold standard of accuracy in timekeeping.
The Impact of the Power Outage
When hurricane force winds moved into Colorado, Xcel Energy preemptively shut off power to protect areas of the state from extreme fire danger. As a result, the NIST Internet Time Service facility in Boulder was affected, and the power to the servers briefly lapsed. This caused a 4 microsecond drift in timekeeping, which is equivalent to 4 millionths of a second. To put this into perspective, it takes about 350,000 microseconds to blink or 150,000 microseconds to snap your fingers. According to NIST spokesperson Rebecca Jacobson, "For most NIST time users, this drift would not even register. For those users in industries such as telecommunications and aerospace, or other laboratories where such a drift could be noticeable, we always provide access to other networks in other locations to ensure uninterrupted service."
The NIST F-4 Atomic Clock
The NIST F-4 atomic clock is a highly accurate timekeeping device that measures an unchanging frequency in the heart of cesium atoms. This frequency is the internationally agreed-upon basis for defining the second since 1967. The clock is so accurate that if it had started running 100 million years ago, when dinosaurs roamed, it would be off by less than a second today. The NIST F-4 clock is part of a network of clocks and servers in different locations, which ensures that the timekeeping service remains accurate and reliable even in the event of a power outage. The clock’s accuracy is maintained by a network of clocks and servers in different locations, ensuring minimal impact from the power outage.
Redundancies and Precautions
The NIST Internet Time Service has redundancies in place to ensure uninterrupted service in the event of a power outage. The system is designed to switch to a back-up generator in the event of a power failure, which minimizes the impact on timekeeping. Additionally, high-end users in industries such as telecommunications and aerospace are notified of potential power outages so they can access other networks and ensure uninterrupted service. According to Jacobson, "We had notified those high-end users of a potential power outage so they could be prepared to access those networks as a precaution." This ensures that critical applications that rely on precise timekeeping are not affected by the power outage.
Conclusion and Future Actions
The power outage at the NIST Internet Time Service facility in Boulder was a minor setback, and the system is not at risk. The 4 microsecond drift in timekeeping will be corrected once power is restored to the facility, and the clock is recalibrated. The NIST F-4 atomic clock will continue to provide accurate and reliable timekeeping services to a wide range of applications, including GPS systems, scientific research, and telecommunications. The incident highlights the importance of redundancies and precautions in ensuring the reliability and accuracy of critical infrastructure such as the NIST Internet Time Service.