Earth's journey is right on time

dailycamera.com ^ | Dec 30, 2003 | By Ryan Morgan, Camera Staff Writer

[e_engineer]

The Earth won't be having seconds this year, thank you.

And that has scientists across the world — including those who run the atomic clock at the National Institute for Science and Technology in Boulder — scratching their heads.

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Take a Colorado Ski Vacation Apparently, the Earth isn't slowing down as it used to, and no one knows why.

Flip your calendar back to 1972. That's the year the world began its current system of atomic time-keeping. NIST operates one of the clocks used to set "Coordinated Universal Time."

Scientists soon discovered they had a small problem: The rate at which the Earth travels through space had slowed ever so slightly, and as a result was completing its 365-day journey around the sun one second behind schedule.

To make the world's official time agree with where the Earth actually sat in space, scientists started having the atomic clocks count an extra "leap second" on the last day of the year.

"They came close to matching it, but they had to add a second to keep it in sync," said John Lowe, a NIST researcher who works in the agency's Time and Frequency Division.

For 28 years, scientists repeated the procedure. Then, in 1999, they discovered that the Earth was no longer lagging behind. It didn't need a leap second.

This is the fifth consecutive year that the Earth hasn't lagged behind schedule.

Fred McGehan, a spokesman for NIST, said most scientists agree that the Earth has been very gradually slowing down for millennia. But, he said, they don't have a good explanation for the five years it's been on schedule.

Possible explanations include the tides, weather and changes in the Earth's core.

Contact Ryan Morgan at morganr@dailycamera.com or (303) 473-1333.

[e_engineer]

Hope Dailycamera.com is allowed for full posting.

OK fellow Freepers, Why is the Earth no longer slowing down in orbit?

[Atlas Sneezed]

Global cooling. Because we didn't get warmer, the energy had to go somewhere, which happens to be the offsetting of the natural slowing.

;-)

[Semper Paratus]

Why is the Earth no longer slowing down in orbit?

I got it! Global Warming! The hotter air is making the Earth lighter!

[reed_inthe_wind]

Al Gore hushed his mouth - I said " AAAAAlllll GGooooorrrre huuuuuuushshshshed hiiiisssss mmmououououououththth.

[eldoradude]

Geritol

[RightWhale]

Earth would slow its rotation about the sun if it is moving farther from the sun. Therefore it is not moving farther from the sun. Why? It is possibly beginning its fall into the sun.

[Beck_isright]

"Why is the Earth no longer slowing down in orbit?"

[gitmo]

Double clutching?

[Bear_in_RoseBear]

curiouser ping...

[boris]

"OK fellow Freepers, Why is the Earth no longer slowing down in orbit?"

Careful. Its rotation about its own axis is the question. "In orbit" implies motion about the Sun.

--Boris

[farmfriend]

Doesn't this effect your satellite computations? And is this effecting the other planets?

[Ruy Dias de Bivar]

**The hotter air is making the Earth lighter!***

So, what holds politicians down?

[timpad]

OK fellow Freepers, Why is the Earth no longer slowing down in orbit?

Maybe all that ordinance falling in a small area back in the springtime scooted the ol' gal along just a bit?

[Senator Pardek]

The Atomic Clock Sync app guarantees that I'm exactly 15 minutes late for wherever I have to go.

[Prodigal Son]

Ah, it's the clock. Somebody probably forgot to wind the darned thing and it's running down now.

[Stirner]

Why is the Earth not slowing down?

My assumption is that the slowdown we have observed long-term has been due to friction, both the planet's impact with particles in its path and movement toward gravitational coupling with the Sun's rotation (like the Moon has achieved with the Earth). The first process would make the year longer (or retard its shortening), while the second process would speed the year up (although, as the year shortened, our orbit would move closer to the Sun). These countervailing processes might lead to the departures from trend we see. I don't believe in global warming, but maybe I'm wrong. If the overall temperature of the planet was increasing, would that somehow affect the length of the year?

[boris]

Well I take it back. But I thought the "leap second" was imposed by the non-constant rate of rotation. We know the day is continually slowed by tidal forces from the Moon.

Then there's the issue of sidereal time versus Solar time...

There is also the issue of the Mean Tropical Year versus the Sidereal Year versus the Solar Year...

I'm confused.

--Boris

[secretagent]

The article refers to the 365 day journey around the sun - I think the author intends orbit, not rotation.

[RightWhale]

is this effecting the other planets?

They all affect each other. Another force that might be acting is magnetism. The magnetic field of the sun may have rotated or weakened so it doesn't interact with earth's mag field so strongly.

[Old Professer]

Tailwind?