The Mandelbear's Musings

The headline in The Times is "Earth's time lords make new year wait a second", but it's serious business. This year's leap second will occur at midnight, 2005-12-31 11:59:60 UTC. Think about that time for a moment.

This will be the first leap-second since 1998. It's the subject of a great kurfuffle between the astronomers represented by the Time Lords of the International Earth Rotation and Reference Systems Service (based in Paris) and the US delegation to the International Telecommunication Union. The astronomers naturally want atomic time and astronomical time to match up as closely as possible; the US (representing the computer industry) wants to avoid irregularly-spaced corrections that mess up software that wasn't written to accomodate them. Programmers just want to be able to compute the interval between any two dates without having to consult a manually-maintained table. This becomes important if you need to know the exact time in January, 2038 when 32-bit Unix date-codes roll over.