dantem said:Data said:I would say, if there is a deceleration, it is only in the order of milliseconds or even microseconds a day. But I am sure that there are scientific institutes somewhere out there who constantly measure the earth's rotation speed relative to the stars. Maybe someone could do a little research on this? After all, the C's said once: "You understand the concept, now you must decide if it is factual."Michael said:I'm curious of how much the earths rotation has slowed. If this is the case, how long is a day? If the earths rotation is slowed, it would not make the day longer than 24 hours?
Apparently someone noticed (as far as 2003 in this article), even if they're going on with the wrong explanation:
_http://www.nasa.gov/centers/goddard/news/topstory/2003/0210rotation.html
[...]the rotation of the Earth may slow ever so slightly because of stronger winds, increasing the length of a day by a fraction of a millisecond (thousandth of a second).
There is also this:
https://www.sott.net/articles/show/107491-Wait-a-sec-for-leap-into-2006
Wait a sec for leap into 2006
CNN Sunday, December 25, 2005
Mon, 26 Dec 2005 12:00 EST
WASHINGTON (Reuters) -- Get ready for a minute with 61 seconds. Scientists are delaying the start of 2006 by the first "leap second" in seven years, a timing tweak meant to make up for changes in the Earth's rotation.
The adjustment will be carried out by sticking an extra second into atomic clocks worldwide at the stroke of midnight Coordinated Universal Time, the widely adopted international standard, the U.S. National Institute of Standards and Technology said this week.
"Enjoy New Year's Eve a second longer," the institute said in an explanatory notice. "You can toot your horn an extra second this year."
Coordinated Universal Time coincides with winter time in London. On the U.S. East Coast, the extra second occurs just before 7 p.m. on New Year's Eve. Atomic clocks at that moment will read 23:59:60 before rolling over to all zeros.
A leap second is added to keep uniform timekeeping within 0.9 second of the Earth's rotational time, which can speed up or slow down because of many factors, including ocean tides. The first leap second was added on June 30, 1972, according to NIST, an arm of the U.S. Commerce Department.
High-speed communications systems among other modern technologies require precise time measurements.
Since 1999 until recently, the two time standards have been in close enough synch to escape any need to add a leap second, NIST said.
Although it is possible to have a negative leap second -- that is, a second deducted from Coordinated Universal Time -- so far all have been add-ons, reflecting the Earth's general slowing trend due to tidal breaking.
Deciding when to introduce a leap second is the responsibility of the International Earth Rotation and Reference Systems Service, a standards-setting body. Under an international pact, the preference for leap seconds is December 31 or June 30.
So that is one second slower every seven years. It's not much to us, but in a cosmic level it may be very significant. Notice how they claim that in theory the rotation may speed up or slow down, but it just happens that so far it has only slowed down since it's been measured!