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#1




Maybe you sci.astro.amateur and sci.astro readers can explain this
"Common Man" wrote in message
news.com... Note to the readers of sci.astro.amateur and sci.astro: Pearl is a regular in the alt.animals.ethics.vegetarian newsgroup and claims that the earth could be hollow. She goes on to claim that this could have been caused by a rapidly spinning early earth. I've tried to explain (without success) that such a rapidly spinning body would flatten out rather than become hollow. If any of you wish to take a crack at explaining this to her, feel free. For Pearl: Evidence that a rapidly spinning object would flatten out, not become hollow. See: http://www.govertschilling.nl/artike.../030612_sc.htm It's been pointed out to you by someone else that centrifugal force will cause a spherical body to become oblate, without becoming completely flat. Is this a throwback to your past life as chief honcho of the flatearth society, 'common man'? 
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#2




Maybe you sci.astro.amateur and sci.astro readers can explain this
pearl wrote:
It's been pointed out to you by someone else that centrifugal force will cause a spherical body to become oblate, without becoming completely flat. Is this a throwback to your past life as chief honcho of the flatearth society, 'common man'? The Earth IS a oblate spheroid and is modeled very well by the WGS84 ellipsoid and datum NATIONAL GEOSPATIALINTELLIGENCE AGENCY GPS PRECISE EPHEMERIDES, SATELLITE CLOCK PARAMETERS AND SMOOTHED OBSERVATIONS PRECISE EPHEMERIS Earthcentered Earthfixed trajectory Coordinate system: WGS84 (G1150) Position  x,y,z (km) Velocity  dx/dt,dy/dt,dz/dt (dm/s) GPS time  year, day, hour, minute Trajectory interval: 15 min. Standard Trajectory referenced to satellite center of mass Optional Trajectory referenced to satellite antenna phase center SATELLITE CLOCK PARAMETERS Clock parameters for each satellite: Time offset (microseconds) Frequency offset (10E4 microsec/s = parts in 10E10) Time interval for parameters: 15 min. Satellite clock events: All events processed as reinitializations SMOOTHED OBSERVATIONS Smoothed range and range difference observations (km) with corrections applied (see below) GPS time of observation (year, day, seconds from beginning of day) Standard deviation of observation (km) Coordinate system: WGS84 (G1150) Station coordinates: Position  x,y,z (m), Epoch 2001.0 Velocity  dx/dt,dy/dt,dz/dt (m/year) Temperature (degrees Celsius) Pressure (millibars) Humidity (percent) Data interval: 15 min. Smoothing uses carrier phase to smooth range and range difference measurements collected at a 1.5 second rate for NIMA and Air Force monitor stations and at a 30 second rate for IGS monitor stations Minimum elevation angle for observation: 10 degrees National Imagery and Mapping Agency and Air Force monitor station data collected and smoothed using similar procedures References: Computer Program Development Spec., Master Control Station, Ephemeris/Clock Computer Program, NAVSTAR GPS Operational Control System Segment, CPMCSEC302C, Part 1, Appendix A, 7 May1993. Description of the Smoothing Algorithm in the NIMA Monitor Station Network, (MSN29), Applied Research Laboratories, The University of Texas at Austin, GRSGG971, 3 April 1997. PHYSICAL CONSTANTS GM(Earth) = 398600.4418 km**3/s**2 GM(Sun) = 132712400000 km**3/s**2 GM(Moon) = 4902.799186 km**3/s**2 Moon radius = 1738 km Sun radius = 696000 km Earth semimajor axis (a) = 6378.137 km Inverse flattening (1/f) = 298.257223563 Earth angular velocity = 0.72921158553 X 10**4 Rad/s Speed of light = 299792.458 km/s Love's constant = 0.290 Solar constant = 4.560 X 10**6 N/m**2 Astronomical Unit = 149597870.691 km STATION COORDINATES (GEODETIC) WGS84 (G1150) Epoch 2001.0 STATION COORDINATES (CARTESIAN) WGS84 (G1150) Epoch 2001.0 Due to security concerns surrounding the current threat situations, the coordinates for the NGA/Air Force/IGS stations have been removed. Any such information needed about the NGA stations should be requested, until further notice, at: (314) 2634120 or DSN 6934120 CORRECTIONS APPLIED TO MEASUREMENTS Ionospheric delay: 2frequency, 1st order correction Tropospheric refraction: Saastamoinen hydrostatic and wet zenith delay models and Niell hydrostatic and wet mapping functions Periodic relativistic effects Satellite antenna offset (satellite body centered coordinates, meters) Block II PRN's  Delta x= 0.2794, Delta y= 0.0000, Delta z= 0.9519 Block IIA PRN's  Delta x= 0.2794, Delta y= 0.0000, Delta z= 0.9519 Block IIR PRN 11  Delta x= 0.0019, Delta y= 0.0011, Delta z= 1.5141 Block IIR PRN 13  Delta x= 0.0024, Delta y= 0.0025, Delta z= 1.6140 Block IIR PRN 14  Delta x= 0.0018, Delta y= 0.0002, Delta z= 1.6137 Block IIR PRN 16  Delta x= 0.0098, Delta y= 0.0060, Delta z= 1.6630 Block IIR PRN 18  Delta x= 0.0098, Delta y= 0.0060, Delta z= 1.5923 Block IIR PRN 19  Delta x= 0.0100, Delta y= 0.0064, Delta z= 1.5620 Block IIR PRN 20  Delta x= 0.0022, Delta y= 0.0014, Delta z= 1.6140 Block IIR PRN 21  Delta x= 0.0023, Delta y= 0.0006, Delta z= 1.5840 Block IIR PRN 22  Delta x= 0.0018, Delta y= 0.0009, Delta z= 0.0598 Block IIR PRN 28  Delta x= 0.0018, Delta y= 0.0007, Delta z= 1.5131 Station displacement due to tides Yaw Bias: JPL yaw bias model for Block II and IIA satellites in eclipse, except PRN's 2, and 23 FORCE MODELING Gravitational: EGM96 Earth gravity model truncated at degree 12 and order 12 Solar and Lunar gravity using the DE403 ephemeredes, J2000 epoch, and IAU Resolutions on Astronomical Constants, Time Scales, and the Fundamental Reference Frame (19761980) Solid Earth tides Nongravitational: Radiation Pressure ROCKWELL ROCK42 model for Block II and IIA satellites Lockheed Martin table look up model for Block IIR satellites Thrusts Momentum dumps Kinematic: Lunisolar and planetary precession (IAU Resolutions, as above) Nutation (IAU Resolutions, as above) Earth rotation (IAU Resolutions, as above) Polar Motion (using NIMA initial values generated the week before the orbit fit) + diurnal and semidiurnal effects UT1UTC (using NIMA initial values generated the week before the orbit fit) + Zonal tide effects + diurnal and semidiurnal effects Integration step size: 300 seconds, reduced to 10 seconds during eclipse boundary crossings ORBIT ESTIMATION METHOD Kalman Filter/RTS Smoother (Square Root Information implementation) Initial conditions: From previous fit Solution parameters: Satellite state vector in element form at trajectory epoch  semimajor axis eccentricity * sin(argument of perigee) eccentricity * cos(argument of perigee) inclination mean anomaly + argument of perigee right ascension of the ascending node Satellite clock parameters  Time offset, Frequency offset Monitor station clock parameters (excluding master station)  Time offset, Frequency offset Polar motion parameters  Pole and pole rate components along Greenwich meridian, Pole and pole rate components along meridian 90 deg west of Greenwich, Rate of change and acceleration of UT1UTC Satellite radiation pressure parameters  Radiation pressure scale, and Yaxis acceleration Tropospheric refraction  One stochastic zenith delay parameter per station Minimum range observation uncertainty(1sigma):100 cm (IGS Stations) 100 cm (Station 85128) 80 cm (Station 85130) 40 cm (other stations) Minimum range difference observation uncertainty (1sigma): 1.5 cm Process noise in Kalman Filter: Radiation pressure (each satellite) Decorrelation time 14,400 s Steady state sigmas  SCALE 0.05 YAXIS 0.5 X 10**12 km/s**2 Tropospheric refraction variance rate: 2.89 cm**2/hr Station clock white noise spectral density: (each station)  Time offset 0.1111 X 10**2 (microseconds)**2/s Frequency offset 0.1111 X 10**8 (ppm)**2/s Satellite clock white noise spectral density: (each satellite) Time offset 0.1111 X 10**2 (microseconds)**2/s Frequency offset 0.1111 X 10**8 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s SATELLITE CLOCK ESTIMATION METHOD Kalman Filter/RTS Smoother (Square Root Information implementation) Orbit solutions from above method are held fixed for satellite clock estimation Solution parameters: Satellite clock parameters  Time offset, Frequency offset Monitor station clock parameters (excluding master station)  Time offset, Frequency offset Tropospheric refraction  One stochastic zenith delay parameter per station. Minimum range observation uncertainty(1sigma):100 cm (IGS Stations) 100 cm (Station 85128) 80 cm (Station 85130) 40 cm (other stations) Minimum range difference observation uncertainty (1sigma): 15.0 cm Process noise in Kalman Filter: Tropospheric refraction variance rate: 2.89 cm**2/hr Station clock white noise spectral densities: NGA stations and Air Force Colorado Springs station: Time offset 0.1944 X 10**8 (microseconds)**2/s Frequency offset 0.4440 X 10**19 (ppm)**2/s Air Force stations (except Colorado Springs) and IGS stations: Time offset 0.3456 X 10**8 (microseconds)**2/s Frequency offset 0.4440 X 10**19 (ppm)**2/s Satellite clock white noise spectral densities: Satellite Block IIR Rubidium clocks Time offset 0.8640 X 10**9 (microseconds)**2/s Frequency offset 0.1110 X 10**18 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s Satellite Block II/IIA Rubidium clocks Time offset 0.1944 X 10**8 (microseconds)**2/s Frequency offset 0.1110 X 10**18 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s Satellite Cesium clocks Time offset 0.13824 X 10**7 (microseconds)**2/s Frequency offset 0.1000 X 10**17 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s Satellite 'Noisy' Cesium clocks Time offset 0.2000 X 10**7 (microseconds)**2/s Frequency offset 0.1110 X 10**16 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s 
#3




Maybe you sci.astro.amateur and sci.astro readers can explain this
pearl wrote:
It's been pointed out to you by someone else that centrifugal force will cause a spherical body to become oblate, without becoming completely flat. Is this a throwback to your past life as chief honcho of the flatearth society, 'common man'? The Earth IS a oblate spheroid and is modeled very well by the WGS84 ellipsoid and datum NATIONAL GEOSPATIALINTELLIGENCE AGENCY GPS PRECISE EPHEMERIDES, SATELLITE CLOCK PARAMETERS AND SMOOTHED OBSERVATIONS PRECISE EPHEMERIS Earthcentered Earthfixed trajectory Coordinate system: WGS84 (G1150) Position  x,y,z (km) Velocity  dx/dt,dy/dt,dz/dt (dm/s) GPS time  year, day, hour, minute Trajectory interval: 15 min. Standard Trajectory referenced to satellite center of mass Optional Trajectory referenced to satellite antenna phase center SATELLITE CLOCK PARAMETERS Clock parameters for each satellite: Time offset (microseconds) Frequency offset (10E4 microsec/s = parts in 10E10) Time interval for parameters: 15 min. Satellite clock events: All events processed as reinitializations SMOOTHED OBSERVATIONS Smoothed range and range difference observations (km) with corrections applied (see below) GPS time of observation (year, day, seconds from beginning of day) Standard deviation of observation (km) Coordinate system: WGS84 (G1150) Station coordinates: Position  x,y,z (m), Epoch 2001.0 Velocity  dx/dt,dy/dt,dz/dt (m/year) Temperature (degrees Celsius) Pressure (millibars) Humidity (percent) Data interval: 15 min. Smoothing uses carrier phase to smooth range and range difference measurements collected at a 1.5 second rate for NIMA and Air Force monitor stations and at a 30 second rate for IGS monitor stations Minimum elevation angle for observation: 10 degrees National Imagery and Mapping Agency and Air Force monitor station data collected and smoothed using similar procedures References: Computer Program Development Spec., Master Control Station, Ephemeris/Clock Computer Program, NAVSTAR GPS Operational Control System Segment, CPMCSEC302C, Part 1, Appendix A, 7 May1993. Description of the Smoothing Algorithm in the NIMA Monitor Station Network, (MSN29), Applied Research Laboratories, The University of Texas at Austin, GRSGG971, 3 April 1997. PHYSICAL CONSTANTS GM(Earth) = 398600.4418 km**3/s**2 GM(Sun) = 132712400000 km**3/s**2 GM(Moon) = 4902.799186 km**3/s**2 Moon radius = 1738 km Sun radius = 696000 km Earth semimajor axis (a) = 6378.137 km Inverse flattening (1/f) = 298.257223563 Earth angular velocity = 0.72921158553 X 10**4 Rad/s Speed of light = 299792.458 km/s Love's constant = 0.290 Solar constant = 4.560 X 10**6 N/m**2 Astronomical Unit = 149597870.691 km STATION COORDINATES (GEODETIC) WGS84 (G1150) Epoch 2001.0 STATION COORDINATES (CARTESIAN) WGS84 (G1150) Epoch 2001.0 Due to security concerns surrounding the current threat situations, the coordinates for the NGA/Air Force/IGS stations have been removed. Any such information needed about the NGA stations should be requested, until further notice, at: (314) 2634120 or DSN 6934120 CORRECTIONS APPLIED TO MEASUREMENTS Ionospheric delay: 2frequency, 1st order correction Tropospheric refraction: Saastamoinen hydrostatic and wet zenith delay models and Niell hydrostatic and wet mapping functions Periodic relativistic effects Satellite antenna offset (satellite body centered coordinates, meters) Block II PRN's  Delta x= 0.2794, Delta y= 0.0000, Delta z= 0.9519 Block IIA PRN's  Delta x= 0.2794, Delta y= 0.0000, Delta z= 0.9519 Block IIR PRN 11  Delta x= 0.0019, Delta y= 0.0011, Delta z= 1.5141 Block IIR PRN 13  Delta x= 0.0024, Delta y= 0.0025, Delta z= 1.6140 Block IIR PRN 14  Delta x= 0.0018, Delta y= 0.0002, Delta z= 1.6137 Block IIR PRN 16  Delta x= 0.0098, Delta y= 0.0060, Delta z= 1.6630 Block IIR PRN 18  Delta x= 0.0098, Delta y= 0.0060, Delta z= 1.5923 Block IIR PRN 19  Delta x= 0.0100, Delta y= 0.0064, Delta z= 1.5620 Block IIR PRN 20  Delta x= 0.0022, Delta y= 0.0014, Delta z= 1.6140 Block IIR PRN 21  Delta x= 0.0023, Delta y= 0.0006, Delta z= 1.5840 Block IIR PRN 22  Delta x= 0.0018, Delta y= 0.0009, Delta z= 0.0598 Block IIR PRN 28  Delta x= 0.0018, Delta y= 0.0007, Delta z= 1.5131 Station displacement due to tides Yaw Bias: JPL yaw bias model for Block II and IIA satellites in eclipse, except PRN's 2, and 23 FORCE MODELING Gravitational: EGM96 Earth gravity model truncated at degree 12 and order 12 Solar and Lunar gravity using the DE403 ephemeredes, J2000 epoch, and IAU Resolutions on Astronomical Constants, Time Scales, and the Fundamental Reference Frame (19761980) Solid Earth tides Nongravitational: Radiation Pressure ROCKWELL ROCK42 model for Block II and IIA satellites Lockheed Martin table look up model for Block IIR satellites Thrusts Momentum dumps Kinematic: Lunisolar and planetary precession (IAU Resolutions, as above) Nutation (IAU Resolutions, as above) Earth rotation (IAU Resolutions, as above) Polar Motion (using NIMA initial values generated the week before the orbit fit) + diurnal and semidiurnal effects UT1UTC (using NIMA initial values generated the week before the orbit fit) + Zonal tide effects + diurnal and semidiurnal effects Integration step size: 300 seconds, reduced to 10 seconds during eclipse boundary crossings ORBIT ESTIMATION METHOD Kalman Filter/RTS Smoother (Square Root Information implementation) Initial conditions: From previous fit Solution parameters: Satellite state vector in element form at trajectory epoch  semimajor axis eccentricity * sin(argument of perigee) eccentricity * cos(argument of perigee) inclination mean anomaly + argument of perigee right ascension of the ascending node Satellite clock parameters  Time offset, Frequency offset Monitor station clock parameters (excluding master station)  Time offset, Frequency offset Polar motion parameters  Pole and pole rate components along Greenwich meridian, Pole and pole rate components along meridian 90 deg west of Greenwich, Rate of change and acceleration of UT1UTC Satellite radiation pressure parameters  Radiation pressure scale, and Yaxis acceleration Tropospheric refraction  One stochastic zenith delay parameter per station Minimum range observation uncertainty(1sigma):100 cm (IGS Stations) 100 cm (Station 85128) 80 cm (Station 85130) 40 cm (other stations) Minimum range difference observation uncertainty (1sigma): 1.5 cm Process noise in Kalman Filter: Radiation pressure (each satellite) Decorrelation time 14,400 s Steady state sigmas  SCALE 0.05 YAXIS 0.5 X 10**12 km/s**2 Tropospheric refraction variance rate: 2.89 cm**2/hr Station clock white noise spectral density: (each station)  Time offset 0.1111 X 10**2 (microseconds)**2/s Frequency offset 0.1111 X 10**8 (ppm)**2/s Satellite clock white noise spectral density: (each satellite) Time offset 0.1111 X 10**2 (microseconds)**2/s Frequency offset 0.1111 X 10**8 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s SATELLITE CLOCK ESTIMATION METHOD Kalman Filter/RTS Smoother (Square Root Information implementation) Orbit solutions from above method are held fixed for satellite clock estimation Solution parameters: Satellite clock parameters  Time offset, Frequency offset Monitor station clock parameters (excluding master station)  Time offset, Frequency offset Tropospheric refraction  One stochastic zenith delay parameter per station. Minimum range observation uncertainty(1sigma):100 cm (IGS Stations) 100 cm (Station 85128) 80 cm (Station 85130) 40 cm (other stations) Minimum range difference observation uncertainty (1sigma): 15.0 cm Process noise in Kalman Filter: Tropospheric refraction variance rate: 2.89 cm**2/hr Station clock white noise spectral densities: NGA stations and Air Force Colorado Springs station: Time offset 0.1944 X 10**8 (microseconds)**2/s Frequency offset 0.4440 X 10**19 (ppm)**2/s Air Force stations (except Colorado Springs) and IGS stations: Time offset 0.3456 X 10**8 (microseconds)**2/s Frequency offset 0.4440 X 10**19 (ppm)**2/s Satellite clock white noise spectral densities: Satellite Block IIR Rubidium clocks Time offset 0.8640 X 10**9 (microseconds)**2/s Frequency offset 0.1110 X 10**18 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s Satellite Block II/IIA Rubidium clocks Time offset 0.1944 X 10**8 (microseconds)**2/s Frequency offset 0.1110 X 10**18 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s Satellite Cesium clocks Time offset 0.13824 X 10**7 (microseconds)**2/s Frequency offset 0.1000 X 10**17 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s Satellite 'Noisy' Cesium clocks Time offset 0.2000 X 10**7 (microseconds)**2/s Frequency offset 0.1110 X 10**16 (ppm)**2/s Frequency drift 0. (ppm/s)**2/s 
#4




Maybe you sci.astro.amateur and sci.astro readers can explain this
"Sam Wormley" wrote in message ...
pearl wrote: It's been pointed out to you by someone else that centrifugal force will cause a spherical body to become oblate, without becoming completely flat. Is this a throwback to your past life as chief honcho of the flatearth society, 'common man'? The Earth IS a oblate spheroid and is modeled very well by the WGS84 ellipsoid and datum Wow! .. 
#5




Maybe you sci.astro.amateur and sci.astro readers can explain this
"Sam Wormley" wrote in message ...
pearl wrote: It's been pointed out to you by someone else that centrifugal force will cause a spherical body to become oblate, without becoming completely flat. Is this a throwback to your past life as chief honcho of the flatearth society, 'common man'? The Earth IS a oblate spheroid and is modeled very well by the WGS84 ellipsoid and datum Wow! .. 
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