The Length of a Second Could Change — WTF Does That Mean Exactly?

[WhiteTara]

https://www.yahoo.com/news/length-second-could-change-wtf-195500918.html?nhp=1

Nothing in life is certain. Not even the length of a second, if German researchers are accurate in their calculations. As the Independent reported, a group of them believe they've figured out how to measure a timepiece's ticking with unprecedented accuracy — which means the definition of a second, which has stood unchallenged since 1967, could soon be changed.

"What we demonstrated is a first step towards a global improvement of timekeeping," said Christian Grebing of the National Metrology Institute of Germany and an author of the paper on the clock, according to Science Daily.

Wait... what? Currently, time is measured atomically, using the transition of energy of an atom. Typically, it's a caesium atom, and the 9,192,631,770 transitions within it comprise a second. The International System of Units has defined it as such for nearly half a century.

Grebing and his team, however, swapped strontium atoms in for caesium; according to the Independent, strontium atoms cycle "in the optical, rather than the microwave, part of the spectrum." Atomic clocks measure microwave signals and are highly accurate, but these strontium clocks would be even better, with an error margin of less than .2 nanoseconds in 25 days. Atomic clocks have an error of around one nanosecond every 30 days.

[riversedge]

1. Very interesting. The more accurate the better. I am always amazed at

what real science can do.

[Press Virginia]

2. It means I'll be lasting a little longer in the sack

[dlwickham]

3. way to represent WV!

[jmowreader]

4. Not the length, the definition

In the short term, a cesium clock is dead-on-balls accurate, but over the long term it runs a billionth of a second slow a month. To you and I that's nothing, but to the people for whom time is so critical they sent Hewlett-Packard $57,000 for an atomic clock, that's unacceptably huge. These new strontium clocks will run a billionth of a second slow every five months, which is much better.

[Journeyman]

5. So what will the new length be in 'Mississippis'? . . .

"1.00001 Mississippi, 2.00001 Mississippi . . ."