2/11/2026
We are occasionally asked how frequently GPS jamming or spoofing occurs. There are several methods for detecting such events, one of which involves using data from aircraft. Outputs from one such system can be viewed via the Stanford University project.
26/10/2026
End of leap seconds?
On Thursday, October 15, 2026, the General Conference on Weights and Measures (CGPM) voted to introduce a continuous global time scale, which will eliminate the need to insert leap seconds in the future.
Leap seconds are used to keep Coordinated Universal Time (UTC) aligned with the astronomical time scale (UT1), which is based on the Earth's rotation. The Earth's rotation is not perfectly regular and fluctuates due to natural factors. Historically, it has gradually slowed down, making it necessary to occasionally add a leap second to prevent UTC from drifting away from astronomical time.
In recent years, however, the Earth's rotation has accelerated unusually. This has created a new situation where, for the first time in history, it might become necessary to insert a "negative" leap second.
The CGPM's decision reduces risks for systems that rely on precise and continuous time synchronization, including the national infrastructure upon which we depend daily. Implementing leap seconds is technically challenging; if not done correctly, it can lead to time discrepancies across different networks. These risks would be even greater if a negative leap second had to be introduced for the first time.
Until now, leap seconds have been inserted into the UTC system to keep the difference from UT1 within 0.9 seconds. Starting May 20, 2027, the allowable difference will be up to one hour before any intervention becomes necessary. This will ensure the continuity of the UTC time scale for several centuries or even longer.
22/10/2026
As of today, we have connected a node in Vienna to the CESTime network. It will serve primarily to compare the Czech and Austrian time standards.
12/10/2026
At the LinuxDays 2026 conference, colleague Vladimír Smotlacha gave a lecture "Precise time transmission using the White Rabbit protocol". The lecture recording is on YouTube.
07/10/2026
We have released an introductory video for the CESTime service that provides context for the service as a whole. We recommend viewing the enlarged image in full-screen mode.
30/09/2026
Launch of the academic part of the CESTime network. Users from the fields of science, research and education, as well as other users meeting the e-Infrastructure Access Terms and Conditions, can connect in Prague, Brno, Ostrava, Olomouc, Pardubice, Hradec Králové, Jihlava, České Budějovice, Liberec, Ústí nad Labem and Plzeň.