Re: [guide-user] Re: Phobos transit in Guide

Luc Desamore Sep 5, 2013

Hi Bill,
 
http://www.projectpluto.com/pluto/mpecs/phobos.htm

The event you tried to fit is plotted under horizon (17 aug 10:37) in Guide and in JPL Horizons
 
Did you use the right position of Curiosity to generate your ephemerides  because there are big differencies with azimut and elevation ?
 
Hereunder is the ephemeris with Horizon (Curiosity position not updated) :
 
I noticed that the apparent declination in JPL Horizon is very different from the J2000, this is not the case in Guide.
 
Anyway, do not try to get an eclipse the 17th ;-)
 
Luc
 
 
*******************************************************************************
Ephemeris / WWW_USER Thu Sep  5 02:12:40 2013 Pasadena, USA      / Horizons    
*******************************************************************************
Target body name: Phobos (401)                    {source: MAR097}
Center body name: Mars (499)                      {source: MAR097}
Center-site name: Curiosity Landing Site (MSL) / Gale Crater
*******************************************************************************
Start time      : A.D. 2013-Aug-17 10:37:00.0000 UT      
Stop  time      : A.D. 2013-Aug-17 10:40:00.0000 UT      
Step-size       : 18 steps
*******************************************************************************
Target pole/equ : IAU_PHOBOS                      {East-longitude -}
Target radii    : 13.0 x 11.4 x 9.1 km            {Equator, meridian, pole}    
Center geodetic : -137.40000,-4.4999116,-4.406561 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: -137.40000,3381.45043,-262.9931 {E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : IAU_MARS                        {East-longitude -}
Center radii    : 3396.2 x 3396.2 x 3376.2 km     {Equator, meridian, pole}    
Target primary  : Mars
Vis. interferer : PHOBOS (R_eq= 13.000) km        {source: MAR097}
Rel. light bend : Sun, MARS                       {source: MAR097}
Rel. lght bnd GM: 1.3271E+11, 4.2828E+04 km^3/s^2                              
Atmos refraction: NO (AIRLESS)
RA format       : HMS
Time format     : CAL 
RTS-only print  : NO       
EOP file        : eop.130830.p131121                                           
EOP coverage    : DATA-BASED 1962-JAN-20 TO 2013-AUG-30. PREDICTS-> 2013-NOV-20
Units conversion: 1 au= 149597870.700 km, c= 299792.458 km/s, 1 day= 86400.0 s 
Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass     n.a.    , Daylight (NO )
Table cut-offs 2: Solar Elongation (  0.0,180.0=NO ),Local Hour Angle( 0.0=NO )
***********************************************************************************************
 Date__(UT)__HR:MN:SC.fff     R.A._(ICRF/J2000.0)_DEC R.A.__(a-apparent)__DEC Azi_(a-appr)_Elev
***********************************************************************************************
$$SOE
 2013-Aug-17 10:37:00.000  x  18 08 48.84 -24 53 12.8 18 35 40.11 +02 46 25.8 272.4718  -4.0231
 2013-Aug-17 10:37:10.000  x  18 09 18.86 -24 56 21.0 18 36 10.12 +02 46 31.6 272.4798  -3.9392
 2013-Aug-17 10:37:20.000  x  18 09 48.92 -24 59 28.8 18 36 40.15 +02 46 37.4 272.4878  -3.8551
 2013-Aug-17 10:37:30.000  x  18 10 19.01 -25 02 36.4 18 37 10.18 +02 46 43.2 272.4958  -3.7711
 2013-Aug-17 10:37:40.000  x  18 10 49.15 -25 05 43.6 18 37 40.23 +02 46 48.9 272.5038  -3.6869
 2013-Aug-17 10:37:50.000  x  18 11 19.32 -25 08 50.5 18 38 10.29 +02 46 54.7 272.5118  -3.6028
 2013-Aug-17 10:38:00.000  x  18 11 49.54 -25 11 57.0 18 38 40.36 +02 47 00.4 272.5198  -3.5185
 2013-Aug-17 10:38:10.000  x  18 12 19.79 -25 15 03.2 18 39 10.45 +02 47 06.2 272.5278  -3.4343
 2013-Aug-17 10:38:20.000  x  18 12 50.08 -25 18 09.1 18 39 40.54 +02 47 11.9 272.5358  -3.3499
 2013-Aug-17 10:38:30.000  x  18 13 20.41 -25 21 14.6 18 40 10.65 +02 47 17.6 272.5438  -3.2656
 2013-Aug-17 10:38:40.000  x  18 13 50.78 -25 24 19.7 18 40 40.77 +02 47 23.3 272.5519  -3.1811
 2013-Aug-17 10:38:50.000  x  18 14 21.19 -25 27 24.6 18 41 10.91 +02 47 29.0 272.5599  -3.0967
 2013-Aug-17 10:39:00.000  x  18 14 51.64 -25 30 29.0 18 41 41.05 +02 47 34.6 272.5679  -3.0121
 2013-Aug-17 10:39:10.000  x  18 15 22.12 -25 33 33.2 18 42 11.21 +02 47 40.3 272.5760  -2.9276
 2013-Aug-17 10:39:20.000  x  18 15 52.65 -25 36 36.9 18 42 41.38 +02 47 46.0 272.5840  -2.8429
 2013-Aug-17 10:39:30.000  x  18 16 23.22 -25 39 40.4 18 43 11.56 +02 47 51.6 272.5921  -2.7582
 2013-Aug-17 10:39:40.000  x  18 16 53.82 -25 42 43.4 18 43 41.76 +02 47 57.2 272.6002  -2.6735
 2013-Aug-17 10:39:50.000  x  18 17 24.47 -25 45 46.1 18 44 11.96 +02 48 02.8 272.6082  -2.5887
 2013-Aug-17 10:40:00.000  x  18 17 55.16 -25 48 48.5 18 44 42.18 +02 48 08.4 272.6163  -2.5039
$$EOE