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Author Topic: If the Earth's rotation is slowing, how long before a year leasts 366 days?  (Read 3629 times)

Kevin_McCrohan

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Kevin_McCrohan  asked the Naked Scientists:
   
Hi Chris

I was just wondering that as the earth's rotation is slowing has anyone
actually calculated when the earth's year would take 366 days.

Kevin

Adelaide
South Australia

What do you think?


 

Offline yor_on

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"The Earth is constantly undergoing a deceleration caused by the braking action of the ocean tides. Through the use of ancient observations of eclipses, it is possible to determine the deceleration of the Earth to be roughly 2 milliseconds per day per century.

This is an effect which causes the Earth's rotational time to slow with respect to the atomic clock time. Since it has been about 1 century since the defining epoch (i.e., the duration since 1900), the difference has accumulated to roughly 2 milliseconds per day. Other factors also affect the Earth's dynamics, some in unpredictable ways, so that it is necessary to monitor the Earth's rotation continuously."

http://maia.usno.navy.mil/eo/leapsec.html

And then you need to know how many milliseconds it goes in twenty four hours. Also accounting for the fact that as the Earth slows down every 'solar day' (one full Earth rotation:) minisculely it will take some more time for that 'solar day'. When you've taken that into account you split the number you've got into even parts consisting of two milliseconds each each 'pair' representing a century. Seems simple?
Nah :)

Here is one guy gone 'backwards' :)
Although he seems to have counted on 1.4 milliseconds instead of 2/century.

" Tracing these tiny milliseconds back for 4.5 billion years adds up to a very significant amount of time for a solar day. I have determined that the day/night rotation was 63,000 seconds shorter than the present 86,400 seconds it is today.

This would put the Earth's rotation at about 6.5 hours per day/night cycle, when it was created, 4.5 billion years ago. (This is a much faster rate of rotation than the Cassini-Huygens mission (2003 to 2004) determined Saturn's 10.5 hours rotation period to be.)"

 
 

Offline yor_on

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Thinking of it:)
As our oceans now is storing more energy due to 'global warming'.
Does this mean that this 'braking process' will speed up?
 

Offline Vern

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Fox news came out with a report last night that has global cooling going on. According to the report this cooling is expected to last another 25 years or so until the CO2 begins to cause some warming.

That report came right after the announcement of the new Cap-And-Trade tax our new government gave us. It is expected to cause our utility costs to sky-rocket.

This new administration is so effective that it scares nature into behaving :)
 

Offline yor_on

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Vern, there has been a lot strange weather phenomena lately :)
Maybe there is a cooling effect also, do you have a link to it?
Although if you go to http://www.ncdc.noaa.gov/oa/climate/research/2008/ann/ann08.html you will see their assessment for 2008. There they say that 2008 is the eight warmest year globally since we started to measure temperatures on Earth. And they say the same about December.

And I'm pretty sure the water is warming up. That's one of the 'feedings' for hurricanes. "The 2008 Atlantic hurricane season was the third most costly on record, after 2005 and 2004, and the fourth most active year since 1944. This was the first season with a major hurricane (Category 3 or above) each month from July through November.... Warmer-than-average temperatures occurred throughout the year in most land areas of the world, with the exception of cooler-than-average conditions across Colombia, parts of Alaska, central Canada, and the midwestern continental U.S."


« Last Edit: 06/03/2009 08:50:39 by yor_on »
 

Offline Chemistry4me

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I am sure that the water is warming up. I could tell when I went under.
I said hi to the ocean too. ;)
 

Offline yor_on

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Now Mr Chem?
What are you doing here, shouldn't you be out with the friendly shar.. Ah, dolphins?

---

Isn't it bedtime?
« Last Edit: 06/03/2009 08:55:06 by yor_on »
 

Offline Chemistry4me

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I thought I should pop up out of the water to take another breath. :)
 

Offline Chemistry4me

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Bedtime? Ah...but it is Friday evening.
I am well adapted to little sleep, in fact, I never blink, like my aquatic friends.
 

Offline yor_on

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Ah, and so it started, just when one had that minute of peace.
Well now you had your breath Mr Chem, please try to go to sleep now.
And remember, only one breath at a time due to prevailing weather conditions, time's not awaisting.
 

Offline yor_on

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So are we sleeping yet?

--

This is strange?
Ah well, then.

I'll just go feed my tame polar bears.
Or not?  Hmm, they do look hungry out there.
A night in I think.

What? A knock on the door?
Yes?

ArrGH....
« Last Edit: 06/03/2009 09:38:06 by yor_on »
 

Offline Chemistry4me

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So are we sleeping yet?
Nah, just occupied by some rugby on TV :)
 

Offline Chemistry4me

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Whoops, the ads have just finished :)
 

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