[amsat-bb] Re: Planet Pseudo-Keps
Joe Fitzgerald
jfitzgerald at alum.wpi.edu
Sat Feb 27 10:35:44 PST 2010
Auke de Jong, VE6PWN wrote:
>
> On second thought, the software that runs the fully-automated personal
> telescopes already does most of this, except for the relative velocity part.
>
>
The US government will do that for us via the JPL HORIZONS tracking
system http://ssd.jpl.nasa.gov/?horizons The data below show that as
this being written I should point my antennas to the south, a little
less than half way up from horizon to my zenith. Jupiter is moving away
from me at about six and a half kilometers per second, and a "dit"
leaving my keyer will take the better part of an hour to reach it's target.
No charge to use this, US hams pay for this with our taxes. That being
said you Canadians are welcome to send me cash gifts, and I will be glad
to pay the appropriate US income tax on it!
-Joe KM1P
*******************************************************************************
Revised: Dec 17, 2009 Jupiter 599
PHYSICAL DATA (updated 2009-Jan-28):
Mass (10^24 kg) = 1898.13+-.19 Density (g/cm^3) = 1.326
Equat. radius (1 bar) = 71492+-4 km Polar radius (km) = 66854+-10
Volumetric mean radius= 69911+-6 km Flattening = 0.06487
Rotation period = 9h 55m 29.685s Rot. rate(10^-4 rad/s) = 1.75865
m = w^2a^3/GM = 0.089195 Hydrostatic flat., fh = 0.06509
Inferred rot. period = 9.894+-0.02 hr ks = 3*J2/m = 0.494
Mom. of inert. I/MRo^2= 0.254 I/MRo^2 (upper bound) = 0.267
Rocky core mass (Mc/M)= 0.0261 Y factor (He/H ratio) = 0.18+-0.04
GM (km^3/s^2) = 126,686,511 GM 1-sigma (km^3/s^2) = +-100
Equ. grav, ge (m/s^2) = 24.79 Pol. grav, gp (m/s^2) = 28.34
Geometric albedo = 0.52 Visual magnitude V(1,0)= -9.40
Vis. mag. (opposition)= -2.70 Obliquity to orbit = 3.12 deg
Sidereal orbit period = 11.862615 yr Sidereal orbit period = 4332.820 d
Mean daily motion = 0.0831294 deg/d Mean orbit velocity = 13.0697 km/s
Atmos. temp. (1 bar) = 165+-5 K Heat flow/mass (x10^7) = 15 erg/gm*s
Planetary Solar Const = 50.5 W/m^2 Dipole tilt/offset = 9.6deg/0.1Rp
Escape velocity (km/s)= 59.5 Mag.dip.mom(gauss-Rp^3)= 4.2
Aroche(ice)/Rp = 2.76 Hill's sphere rad. Rp = 740
*******************************************************************************
*******************************************************************************
Ephemeris / WWW_USER Sat Feb 27 10:15:04 2010 Pasadena, USA / Horizons
*******************************************************************************
Target body name: Jupiter (599) {source: JUP230}
Center body name: Earth (399) {source: DE405}
Center-site name: (user defined site below)
*******************************************************************************
Start time : A.D. 2010-Feb-10 17:00:00.0000 UT
Stop time : A.D. 2010-Feb-10 20:00:00.0000 UT
Step-size : 5 minutes
*******************************************************************************
Target pole/equ : IAU_JUPITER {East-longitude -}
Target radii : 71492.0 x 71492.0 x 66854.0 km {Equator, meridian, pole}
Center geodetic : 288.845300,42.2925472,49.999402 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 288.845300,4762.18349,4303.3386 {E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : High-precision EOP model {East-longitude +}
Center radii : 6378.1 x 6378.1 x 6356.8 km {Equator, meridian, pole}
Target primary : Sun {source: DE405+DE408}
Interfering body: MOON (Req= 1737.400) km {source: DE405}
Deflecting body : Sun, EARTH {source: DE405}
Deflecting GMs : 1.3271E+11, 3.9860E+05 km^3/s^2
Atmos refraction: NO (AIRLESS)
RA format : HMS
Time format : CAL
RTS-only print : NO
EOP file : eop.100226.p100520
EOP coverage : DATA-BASED 1962-JAN-20 TO 2010-FEB-26. PREDICTS-> 2010-MAY-19
Units conversion: 1 AU= 149597870.691 km, c= 299792.458 km/s, 1 day= 86400.0 s
Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass (>38.000=NO), Daylight (NO )
Table cut-offs 2: Solar Elongation ( 0.0,180.0=NO )
*****************************************************************************************************************
Date__(UT)__HR:MN Azi_(a-appr)_Elev dAZ*cosE d(ELV)/dt APmag S-brt delta deldot 1-way_LT
*****************************************************************************************************************
$$SOE
2010-Feb-10 17:00 *m 163.9922 35.9868 867.85 184.19 -2.02 5.31 8.8974883901E+08 6.3227121 49.464711
2010-Feb-10 17:05 *m 165.4872 36.2310 871.25 167.40 -2.02 5.31 8.8975073674E+08 6.3287606 49.464817
2010-Feb-10 17:10 *m 166.9922 36.4517 874.35 150.38 -2.02 5.31 8.8975263628E+08 6.3348429 49.464922
2010-Feb-10 17:15 *m 168.5063 36.6486 877.14 133.15 -2.02 5.31 8.8975453766E+08 6.3409553 49.465028
2010-Feb-10 17:20 *m 170.0287 36.8215 879.61 115.74 -2.02 5.31 8.8975644087E+08 6.3470944 49.465134
2010-Feb-10 17:25 *m 171.5582 36.9700 881.74 98.16 -2.02 5.30 8.8975834593E+08 6.3532567 49.465240
2010-Feb-10 17:30 *m 173.0940 37.0941 883.54 80.44 -2.02 5.30 8.8976025284E+08 6.3594385 49.465346
2010-Feb-10 17:35 *m 174.6348 37.1934 884.98 62.60 -2.02 5.30 8.8976216161E+08 6.3656364 49.465452
2010-Feb-10 17:40 *m 176.1796 37.2679 886.07 44.67 -2.02 5.29 8.8976407224E+08 6.3718469 49.465558
2010-Feb-10 17:45 *m 177.7272 37.3175 886.79 26.68 -2.02 5.29 8.8976598473E+08 6.3780662 49.465664
2010-Feb-10 17:50 *m 179.2766 37.3420 887.15 8.64 -2.02 5.29 8.8976789909E+08 6.3842910 49.465771
2010-Feb-10 17:55 *t 180.8265 37.3415 887.15 -9.40 -2.02 5.28 8.8976981532E+08 6.3905176 49.465877
2010-Feb-10 18:00 *m 182.3758 37.3159 886.77 -27.44 -2.02 5.28 8.8977173341E+08 6.3967424 49.465984
2010-Feb-10 18:05 *m 183.9233 37.2653 886.03 -45.43 -2.02 5.27 8.8977365338E+08 6.4029620 49.466091
2010-Feb-10 18:10 *m 185.4680 37.1897 884.93 -63.36 -2.02 5.27 8.8977557520E+08 6.4091726 49.466197
2010-Feb-10 18:15 *m 187.0086 37.0893 883.48 -81.19 -2.02 5.27 8.8977749889E+08 6.4153709 49.466304
2010-Feb-10 18:20 *m 188.5441 36.9643 881.67 -98.90 -2.02 5.26 8.8977942444E+08 6.4215531 49.466411
2010-Feb-10 18:25 *m 190.0734 36.8147 879.52 -116.48 -2.02 5.26 8.8978135184E+08 6.4277158 49.466519
2010-Feb-10 18:30 *m 191.5955 36.6408 877.04 -133.88 -2.02 5.26 8.8978328108E+08 6.4338554 49.466626
2010-Feb-10 18:35 *m 193.1093 36.4429 874.24 -151.10 -2.02 5.25 8.8978521216E+08 6.4399685 49.466733
2010-Feb-10 18:40 *m 194.6139 36.2212 871.13 -168.11 -2.02 5.25 8.8978714507E+08 6.4460514 49.466841
2010-Feb-10 18:45 *m 196.1085 35.9760 867.72 -184.89 -2.02 5.25 8.8978907980E+08 6.4521008 49.466948
2010-Feb-10 18:50 *m 197.5921 35.7077 864.04 -201.43 -2.02 5.25 8.8979101634E+08 6.4581130 49.467056
2010-Feb-10 18:55 *m 199.0640 35.4166 860.08 -217.70 -2.02 5.25 8.8979295468E+08 6.4640847 49.467164
2010-Feb-10 19:00 *m 200.5234 35.1031 855.88 -233.69 -2.02 5.24 8.8979489480E+08 6.4700124 49.467271
2010-Feb-10 19:05 * 201.9698 34.7676 851.44 -249.38 -2.02 5.24 8.8979683669E+08 6.4758927 49.467379
2010-Feb-10 19:10 * 203.4023 34.4105 846.78 -264.78 -2.02 5.24 8.8979878034E+08 6.4817222 49.467488
2010-Feb-10 19:15 * 204.8206 34.0323 841.92 -279.85 -2.02 5.24 8.8980072573E+08 6.4874975 49.467596
2010-Feb-10 19:20 * 206.2242 33.6333 836.87 -294.60 -2.02 5.24 8.8980267285E+08 6.4932152 49.467704
2010-Feb-10 19:25 * 207.6125 33.2141 831.66 -309.02 -2.02 5.25 8.8980462167E+08 6.4988721 49.467812
2010-Feb-10 19:30 * 208.9853 32.7751 826.29 -323.09 -2.02 5.25 8.8980657218E+08 6.5044648 49.467921
2010-Feb-10 19:35 * 210.3423 32.3168 820.79 -336.82 -2.02 5.25 8.8980852435E+08 6.5099901 49.468029
2010-Feb-10 19:40 * 211.6831 31.8396 815.17 -350.20 -2.02 5.25 8.8981047818E+08 6.5154447 49.468138
2010-Feb-10 19:45 * 213.0077 31.3441 809.45 -363.23 -2.02 5.25 8.8981243363E+08 6.5208255 49.468247
2010-Feb-10 19:50 * 214.3158 30.8308 803.64 -375.91 -2.02 5.26 8.8981439068E+08 6.5261292 49.468355
2010-Feb-10 19:55 * 215.6074 30.3001 797.76 -388.24 -2.02 5.26 8.8981634931E+08 6.5313528 49.468464
2010-Feb-10 20:00 * 216.8824 29.7525 791.82 -400.21 -2.02 5.26 8.8981830950E+08 6.5364932 49.468573
$$EOE
*****************************************************************************************************************
Column meaning:
TIME
Prior to 1962, times are UT1. Dates thereafter are UTC. Any 'b' symbol in
the 1st-column denotes a B.C. date. First-column blank (" ") denotes an A.D.
date. Calendar dates prior to 1582-Oct-15 are in the Julian calendar system.
Later calendar dates are in the Gregorian system.
The uniform Coordinate Time scale is used internally. Conversion between
CT and the selected non-uniform UT output scale has not been determined for
UTC times after the next July or January 1st. The last known leap-second
is used over any future interval.
NOTE: "n.a." in output means quantity "not available" at the print-time.
SOLAR PRESENCE (OBSERVING SITE)
Time tag is followed by a blank, then a solar-presence symbol:
'*' Daylight (refracted solar upper-limb on or above apparent horizon)
'C' Civil twilight/dawn
'N' Nautical twilight/dawn
'A' Astronomical twilight/dawn
' ' Night OR geocentric ephemeris
LUNAR PRESENCE WITH TARGET RISE/TRANSIT/SET MARKER (OBSERVING SITE)
The solar-presence symbol is immediately followed by another marker symbol:
'm' Refracted upper-limb of Moon on or above apparent horizon
' ' Refracted upper-limb of Moon below apparent horizon OR geocentric
'r' Rise (target body on or above cut-off RTS elevation)
't' Transit (target body at or past local maximum RTS elevation)
's' Set (target body on or below cut-off RTS elevation)
RTS MARKERS (TVH)
Rise and set are with respect to the reference ellipsoid true visual horizon
defined by the elevation cut-off angle. Horizon dip and yellow-light refraction
(Earth only) are considered. Accuracy is < or = to twice the requested search
step-size.
Azi_(a-appr)_Elev =
Airless apparent azimuth and elevation of target center. Corrected for
light-time, the gravitational deflection of light, stellar aberration,
precession and nutation. Azimuth measured North(0) -> East(90) -> South(180) ->
West(270) -> North (360). Elevation is with respect to plane perpendicular
to local zenith direction. TOPOCENTRIC ONLY. Units: DEGREES
dAZ*cosE d(ELV)/dt =
The rate of change of target center apparent azimuth and elevation
(airless). d(AZ)/dt is multiplied by the cosine of the elevation angle.
TOPOCENTRIC ONLY. Units: ARCSECOND/MINUTE
APmag S-brt =
Target's approximate apparent visual magnitude & surface brightness. For
planets and satellites, values are available only for solar phase angles in the
range generally visible from Earth. This is to avoid extrapolation of models
beyond their valid (data-based) limits. Units: NONE & VISUAL MAGNITUDES PER
SQUARE ARCSECOND
delta deldot =
Range ("delta") and range-rate ("delta-dot") of the target center relative
to the observer at the instant light seen by the observer at print-time would
have left the target center (print-time minus down-leg light-time); the
distance traveled by a light ray emanating from the center of the target and
recorded by the observer at print-time. "deldot" is a projection of the
velocity vector along this ray, the light-time-corrected line-of-sight from
the coordinate center, and indicates relative motion. A positive "deldot" means
the target center is moving away from the observer (coordinate center). A
negative "deldot" means the target center is moving toward the observer.
Units: KM and KM/S
1-way_LT =
1-way down-leg light-time from target center to observer. The elapsed time
since light (observed at print-time) would have left or reflected off a point
at the center of the target. Units: MINUTES
Computations by ...
Solar System Dynamics Group, Horizons On-Line Ephemeris System
4800 Oak Grove Drive, Jet Propulsion Laboratory
Pasadena, CA 91109 USA
Information: http://ssd.jpl.nasa.gov/
Connect : telnet://ssd.jpl.nasa.gov:6775 (via browser)
telnet ssd.jpl.nasa.gov 6775 (via command-line)
*****************************************************************************************************************
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