
	Where results make sense

Topic: International Earth Rotation Service

Related Topics

International Atomic Time

Geostationary orbit

In the News (Tue 22 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	The Earth, Sun, and Moon
		The average distance from the earth to the sun, the semimajor axis of its orbit, is 149,597,890 km.
		This torque is counteracted by the rotation of the earth.
		Because of the elliptical nature of the earth’s orbit and constant changes in the earth’s rate of spin because of the previously mentioned phenomena, the sun, as seen from earth, is moving at a non-uniform rate.
	library.thinkquest.org /29033/begin/earthsunmoon.htm (1847 words)

	Chandler wobble - Wikipedia, the free encyclopedia
		The Chandler wobble is a small variation in Earth's axis of rotation, discovered by American astronomer Seth Carlo Chandler in 1891.
		On 18 July 2000, however, the Jet Propulsion Laboratory announced that "the principal cause of the Chandler wobble is fluctuating pressure on the bottom of the ocean, caused by temperature and salinity changes and wind-driven changes in the circulation of the oceans."
		This was first noted by the International Earth Rotation Service on or about January 5, 2006 as the path of the wobble, usually a widening or tightening spiral depending on the depth of the cycle, made a 90° departure from its predicted track.
	en.wikipedia.org /wiki/Chandler_wobble (595 words)

	International Earth Rotation and Reference Systems Service - Wikipedia, the free encyclopedia
		The International Earth Rotation and Reference Systems Service is the body responsible for maintaining global time and reference frame standards, notably through its Earth Orientation Parameter (EOP) and International Celestial Reference System (ICRS) groups.
		The organization was formerly known as International Earth Rotation Service until April 2, 2002 when it formally changed its name.
		The Sub-bureau for Rapid Service and Predictions of Earth Orientation Parameters of the IERS, located at the United States Naval Observatory, monitors the Earth's rotation.
	en.wikipedia.org /wiki/International_Earth_Rotation_and_Reference_Systems_Service (175 words)

	Earth Slowing Down
		The rotation of the Earth is not intimately related to the length of the year.
		The period of the Earth's orbit around the Sun determines the length of the year, and it is this value that is being synchronized by the leap second program.
		The routine addition of 1 second to the year does not indicate that the Earth's rotation is slowing, but rather that the somewhat complicated devices of the leap year tradition are slightly inaccurate.
	www.rense.com /general38/earth.htm (713 words)

	The Slowing Spin of the Earth
		In association with the slowing rotation of the Earth is the slowing orbit of the Moon.
		Because the Moon is being accelerated in it's orbit, it's distance from the Earth is indicated to increase.
		As Earth rotates on its axis, tidal friction is imposed on it through the gravitational attraction with the Moon and, to a lesser extent, the Sun.
	www.creation-answers.com /slowing.htm (5104 words)

	[No title]
		The uncertainty of the tie of the IRP with the CIO is +/-0.03".
		THE EARTH ORIENTATION PARAMETERS The IERS Earth Orientation Parameters (EOP) are the parameters which describe the rotation of the ITRF to the ICRF, in conjunction with the conventional precession/nutation model.
		Bulletin A is issued by the Sub-Bureau for Rapid Service and Predictions at the U.S. Naval Observatory, Washington; Bulletin B and the Annual Report are issued by the Central Bureau, at the Paris Observatory.
	image.gsfc.nasa.gov /poetry/activity/earthr2.html (4113 words)

	The Geophysical Effects of the Earth's Slowing Rotation!
		If the rate of rotation has been slowing fairly constantly, over the ages, we can see that the earth was rotating very fast originally, for it to slow down to the present 24 hour rate it is today.
		If the Earth's rotation was not slowing, there would be none of this stress, and its shape would have remained constant throughout the ages.
		The surface of the Earth's mantle, especially in the tropical and subtropical regions of the Earth is becoming smaller while the pole regions have uplifted and become rounder.
	novan.com /earth.htm (2102 words)

	Axis of the Earth and Seismicity
		The expert researchers in Paris Observatory, pertaining to IERS (International Earth Rotation Service) show that the effect is not discernible.
		That modifies the earth tensor of inertia which theoretically can affect the movement of the axis of rotation of the earth compared to the crust called the "movement of the pole" or "polhodie".
		The principal components of the motion are a term of period 432 days, the term of Chandler (see here a schematic representation of the Chandler oscillation) attributed to a free mode of the earth as well as a term of 1 year period due to transport of atmospheric masses.
	www.obspm.fr /actual/nouvelle/feb05/sumatra.en.shtml (577 words)

	GeodIS: Earth Rotation & Orientation (Site not responding. Last check: 2007-10-23)
		It is characterized by the rotation vector, which has the direction of the instantaneous spin axis and whose magnitude is the rotational speed.
		The rotation of the Earth is not uniform:
		Precession and nutation are the long-term and the periodic changes of the rotation vector in space.
	dgfi2.dgfi.badw-muenchen.de /typo3_geodis/index.php?id=31 (151 words)

	Earth Rotation and Equatorial Coordinates
		The earth's rotation rate is not uniform, its axis of rotation is not fixed in space, and even its shape and relative positions of its surface locations are not fixed.
		The dominant motion is the precession of the earth's polar axis around the ecliptic pole, mainly due torques on the earth cause by the moon and sun.
		Because of internal motions and shape deformations of the earth, an axis defined by the locations of a set of observatories on the surface of the earth is not fixed with respect to the rotation axis which defines the celestial pole.
	www.cv.nrao.edu /~rfisher/Ephemerides/earth_rot.html (2028 words)

	Earth Rotation (Site not responding. Last check: 2007-10-23)
		The term Earth rotation refers to the spinning of the Earth on its axis...
		Earth's Rotation and the Apparent Daily Motion of the Sky.
		association with the slowing rotation of the Earth is the slowing orbit of...
	www.planetaryvision.net /earthrotation.html (210 words)

	[No title]
		THE EARTH ORIENTATION PARAMETERS The IERS Earth Orientation Parameters (EOP) describe the rotation of the ITRS relative to the ICRS, in conjunction with the conventional Precession-Nutation model.
		Its relationship with the angular velocity of the Earth, Omega, is: Omega = 72 921 151.467064 - 0.843994803 D, where Omega is in picoradians/s and D in ms.
		The operational results are transmitted weekly in parallel to the Sub-bureau for Rapid Service and Predictions to contribute to Bulletin A and to the Central Bureau to contribute to Bulletin B. The refined results are transmitted yearly to the Central Bureau.
	spot.colorado.edu /~kristine/iers.update (2411 words)

	[No title]
		Reigber The International Earth Rotation Service (IERS) was established in 1987 by IAU and IUGG and it started operation on 1988 January 1st.
		It replaces the International Polar Motion Service (IPMS) and the earth-rotation section of the Bureau International de l'Heure (BIH) ; the activities of BIH on time are continued at Bureau International des Poids et Mesures (BIPM).
		The results on earth rotation and reference frames are archived at the network and analysis centres which obtained them, as well as at the Central Bureau.
	www.gfy.ku.dk /~iag/iers95.txt (972 words)

	NASA - Top Story - CHANGES IN THE EARTH'S ROTATION ARE IN THE WIND - March 4, 2003
		NASA’s Earth Science Enterprise (ESE) mission is to understand the Earth system and its response to natural and human-induced changes for better prediction of climate, weather and natural hazards, such as atmospheric changes or El Niño events that may have contributed to the affect on Earth’s rotation.
		During El Niño years, for example, 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).
		Issac Newton’s laws of motion explain how those quantities are related to the Earth's rotation rate (leading to a change in the length of day) as well as the exact position in which the North Pole points in the heavens (known also as polar motion, or Earth wobble).
	www.nasa.gov /centers/goddard/news/topstory/2003/0210rotation.html (953 words)

	The Eternal Purpose of God
		The National Earth Orientation Service (NEOS) as the Sub-bureau for Rapid Service and Predictions of the International Earth Rotation Service (IERS), located at the U.S. Naval Observatory, monitors the Earth's rotation.
		The Earth is constantly undergoing a deceleration caused by the braking action of the tides.
		According to international agreements, first preference is given to the opportunities at the end of December and June, and second preference to those at the end of March and September.
	www.ldolphin.org /studynotes/leapsec.htm (1579 words)

	CDDIS \| Programs
		The International GPS Service (IGS) was established by the International Association of Geodesy (IAG) in 1993 and began formal operation in January 1994.
		IVS is the International VLBI Service for Geodesy and Astrometry.
		The International DORIS Service (IDS) is a project for an international service to provide a support, through DORIS data and products, to geodetic, geophysical, and other research and operational activities.
	cddis.gsfc.nasa.gov /programs.html (2889 words)

	Leap Seconds
		Historically, the second was defined in terms of the rotation of the Earth as 1/86,400 of a mean solar day.
		The Earth's motion was described in Newcomb's Tables of the Sun, which provides a formula for the motion of the Sun at the epoch 1900 based on astronomical observations made during the eighteenth and nineteenth centuries.
		International Atomic Time (TAI) is a statistical atomic time scale based on a large number of clocks operating at standards laboratories around the world that is maintained by the Bureau International des Poids et Mesures; its unit interval is exactly one SI second at sea level.
	tycho.usno.navy.mil /leapsec.html (1741 words)

	International Earth Rotation and Reference Systems Service... - Wikipedia, the free encyclopedia
		Please search for International Earth Rotation and Reference Systems Service...
		Start the International Earth Rotation and Reference Systems Service...
		Look for International Earth Rotation and Reference Systems Service...
	en.wikipedia.org /wiki/International_Earth_Rotation_and_Reference_Systems_Service... (184 words)

	Planet Earth Slowing 0.5 Second/Day(!?!!).
		The change of the Earth rotation of in this book was calculated from the motion of the Moon for old data (since 1620) or from the time measured by atomic clock (since 1984).
		Suddenly, since the year 1900 the Earth rotation began slowing quite rapidly, and it is continuing slowing.
		I found that International Earth Rotation Service (http://maia.usno.navy.mil/)gives a table showing the Earth slowing data (Delta T) from January 1972 to January 2001 (monthly).
	www.zetatalk.com /usenet/use90058.htm (421 words)

	BBC News \| SCI/TECH \| Earth throws a wobbly
		A mysterious wobble that shakes the Earth as it spins on its axis is caused by pressure changes at the bottom of the ocean, say scientists at Nasa's Jet Propulsion Laboratory.
		Similar to a wobble in a spinning top, it is one of a number of tremors exhibited by the Earth as it rotates.
		Using data from International Earth Rotation Service, in Paris, Gross says that two thirds of the wobble can be attributed to these ocean bottom pressure changes and one third to alterations in atmospheric pressure.
	news.bbc.co.uk /1/low/sci/tech/839627.stm (359 words)

	International Earth Rotation Service - IERS
		According to the Terms of Reference of the service, "the Directing Board exercises general control over the activities of the service, including modifications to the organisation and participation that would be appropriate to maintain efficiency and reliability, while taking full advantage of the advances in technology and in theory".
		Maintaining the International Celestial Reference Frame (ICRF) based on VLBI-derived directions of extragalactic radio sources, and of the tie of the Hipparcos galactic reference frame, as will be recommended by the IAU Working Group on Reference Frames to the 1997 IAU General Assembly.
		Monitoring the global geophysical fluids that influence both the ground measurements and the Earth's rotation, an extension of the current activity on atmospheric data.
	www.gfy.ku.dk /~iag/Travaux_99/sec5_iers.htm (1268 words)

	Motivation
		In this introduction, we present the motivation for an expansion of activities of the International Earth Rotation Service (IERS) as discussed at a workshop held at the Paris Observatory in October, 1996 (Reigber and Feissel, 1997).
		IERS activities continue a century-old tradition of international cooperation in the determination of the EOP, relying, in the absence of formal funding, on a variety of national agencies responsible for time keeping, positioning, and scientific research.
		Consequently, the IERS is presently involved in the publication of geodetic standards, the realization of international terrestrial and celestial reference frames, and the monitoring of AAM changes, a major cause of Earth rotation variations.
	www.astro.oma.be /SBC/intro.html (724 words)

	LiveScience.com - A New Spin on Earth's Rotation
		Because the dominant relationship in Salstein’s observations is between wind and rotation, he attempts to predict the Earth’s rotation from long-range weather forecasts.
		Although weather might seem to be immune to millisecond changes in the Earth’s rotation, it should be remembered that the Earth’s rotation does play an important part in creating general weather patterns.
		It may be that rotation and weather are so intricately tied that it may not make sense to speak of cause and effect.
	www.livescience.com /forcesofnature/050225_wobbly_planet.html (1044 words)

	Science/leap seconds
		The atomic second was set equal, then, to an average second of Earth rotation time near the turn of the 20th century.
		The Sub-bureau for Rapid Service and Predictions of the International Earth Rotation Service (IERS), located at the USNO, monitors the Earth's rotation.
		International Atomic Time (TAI) is the atomic time scale of the BIPM; its unit interval is exactly one SI second at sea level.
	www.tafkac.org /science/leap_seconds.html (992 words)

	IERS Rapid Service/Prediction Center for Earth Orientation (Site not responding. Last check: 2007-10-23)
		This service is primarily intended for real-time users and others needing the highest quality EOP information sooner than is available in the IERS final series (Bulletin B) published by the IERS Earth Orientation Center, which is based at the Observatoire de Paris.
		This Center is an activity of the Earth Orientation (EO) Department at the U.S. Naval Observatory (USNO).
		The mission of the USNO includes determining the positions and motions of celestial bodies, measuring the Earth's rotation and orientation, maintaining the master clock for the U.S., and disseminating precise time (atomic and astronomical).
	maia.usno.navy.mil (1050 words)

	Welcome to CreationEvidence.net
		The rotation of the earth is gradually slowing due to the gravitational drag forces of the sun, moon and other factors.
		If the earth is six thousand years old like the Bible says, this is not a problem.
		However, if the earth is billions of years old, the days and nights would be pretty quick.
	www.creationevidence.net /evspace.shtml (221 words)

	Main Astronomical Observatory of National Academy of Sciences of Ukraine
		Beginning with 1970, new methods for the determination of the parameters of Earth rotation (laser ranging, VLBI observations, radio observations of the navigation satellites GPS, GLONASS, etc.) and their analysis were elaborated.
		The investigations of the Department are concerned with a wide range of fundamental and applied problems in astrometry and global geodynamics, from the theory of Earth's rotation to the creation of coordinate systems for the Earth and space.
		Study of the rotation of the Earth and global geodynamics by space geodesy techniques (SLR, VLBI, GPS).
	www.mao.kiev.ua /eng/dept/geodin_e.html (703 words)

	The International Celestial Reference Frame
		Adopted by the International Astronomical Union as the fundamental celestial reference frame, replacing the FK5 optical frame as of 1 January 1998.
		The final orientation of the frame axes has been obtained by a rotation of the positions into the system of the International Celestial Reference System and is consistent with the FK5 J2000.0 optical system, within the limits of the link accuracy.
		The resulting International Celestial Reference Frame has been adopted by the International Astronomical Union as the fundamental celestial reference frame, replacing the FK5 optical frame as of 1998 January 1.
	rorf.usno.navy.mil /ICRF (604 words)

	GGFC Special Bureau for Tides (Site not responding. Last check: 2007-10-23)
		The center exists under the auspices of the International Earth Rotation Service.
		A workshop on "Combination Research and Global Geophysical Fliuds" was recently convened by the International Earth Rotation Service at the Bavarian Academy of Sciences in Munich, Germany, 18-21 November 2002.
		As of 1 January 2001 the International Earth Rotation Service was reorganized.
	bowie.gsfc.nasa.gov /ggfc/tides (381 words)

Try your search on: Qwika (all wikis)