Got a Second? Neil deGrasse Tyson Tells Us Why Today Will Run a Little Long

| 30 Jun 2015 12:55

If today feels like it's lasting forever, there is a reason for that - the world is adding a "leap" second at midnight on June 30th. Why? Blame the moon.

The last minute of the day before midnight tonight, June 30th, will have sixty-one seconds, and it's (mostly) the moon's fault.

Neil deGrasse Tyson, director of New York's Hayden Planetarium, current host of Cosmos, and pretty cool guy, told, "The moon is slowing us down. It's tugging on us."

The effect that Earth's satellite is having is extremely negligible - it amounts to gaining about one second every three years. "If [the moon] ultimately succeeds at this, Earth's rotation will be as slow as the lunar month, and we will always show the same face to one another in what is called a 'double tidal lock,'" says Tyson. "But if you do the math, it will take longer than the lifespan of the sun for the moon to succeed at this."

"So it's not something you should worry about at this point."

Indeed, the extra second may have some people worrying about a Y2K-type event, where throwing off computer clocks by a single second could cause market meltdowns and other catastrophes related to clock-dependant automation. In all likelihood, nothing of the sort will happen - much like Y2K itself.

Will Our Moon Get Its Own Moon?

Other factors beyond the moon's gravity involved in the leap second include the sloshing of the Earth's molten core, the melting of the ice caps, and the effects of the sun's own gravity.

Since 1972, international timekeeping has been maintained in accordance with an atomic time scale - usually referred to as the atomic clock. It works by measuring the state of subatomic particles - the electrons around a cesium atom, usually - as they pass through radio waves. We measure time by the predictable reaction these electrons have to the radiation.

While this clock is as close to a perfect timekeeping device as we can invent, it has its faults. Combined with less-than-predictable factors like the effects of gravity from celestial bodies, the clock needs a little update every now and then to keep things straight: there have been 25 leap seconds added since its introduction.

Has Earth's freeloading satellite finally gone too far? We've put up with the tides, bad poetry - but this is too much. Neil deGrasse Tyson killed Pluto - it's time for his next mission.


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