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Long Term Ephemerides : JPL DE441 vs. JPL DE431

On next version of Uruk_One the long term ephemeris DE431 willl be replaced with the newer (and hopefully better accurate) DE441. I”m currently testing the new binary files that I”ve just generated to see if everything”s all right. What left me speechless it”s the remarkable difference in longitude (ecliptical J2000) shown by the Moon, meaning that I will have to adjust the DeltaT recalibration before releasing the new software. Actually I don”t know if Ryan S. Park and the others used the same previous value for the tidal acceleration of Moon (the published documentation is not freely accessible so far) so I just take note of the new lunar orbit. Most likely the new binary files will be a unified version, with no differences between Windows and other operating systems.

That said, here”s a test comparing the two ephemerides. I chose three dates, BCE 13000, then a typical historical date, BCE 3000 and finally the starting epoch, common between DE431 and DE441, where the results of the calculation basically coincide.

Julian Date Number (Terrestrial Time) : -3026826.5 (BCE 13000/01/01 0 TDT)
 
 J2000 - Heliocentric geometric ecliptical coordinates. JPL DE431
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 Object              Longitude           Latitude         Distance from Sun(AU)      
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 Earth               208° 36' 58.471"   +00° 06' 49.11"   01.016 844 827 730    
 Mercury             251° 25' 07.663"   -00° 44' 01.85"   00.459 804 791 574    
 Venus               276° 32' 58.310"   +00° 53' 14.29"   00.733 983 311 999    
 Mars                141° 01' 06.221"   +02° 13' 54.46"   01.581 960 485 275    
 Jupiter             226° 37' 53.320"   +01° 28' 26.57"   05.333 017 140 965    
 Saturn              346° 29' 53.496"   -00° 33' 24.81"   08.824 722 568 862    
 Uranus              125° 57' 39.119"   +00° 51' 35.41"   18.375 331 498 185    
 Neptune             292° 22' 18.202"   +00° 36' 23.74"   30.175 809 896 253    
 Pluto               342° 58' 00.634"   -13° 31' 23.59"   42.156 717 418 257    
 Moon (GEOCENTRIC)   216° 26' 02.249"   -05° 09' 06.96"   404969.063 Km         
 -------------------------------------------------------------------------------

 J2000 - Heliocentric geometric ecliptical coordinates. JPL DE441
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 Object              Longitude           Latitude         Distance from Sun(AU)      
 -------------------------------------------------------------------------------
 Earth               208° 36' 33.227"   +00° 06' 50.00"   01.016 843 384 563    
 Mercury             251° 23' 52.954"   -00° 43' 51.72"   00.459 817 918 288    
 Venus               276° 32' 16.999"   +00° 53' 16.21"   00.733 982 712 662    
 Mars                141° 00' 54.960"   +02° 13' 54.18"   01.581 966 493 493    
 Jupiter             226° 37' 53.051"   +01° 28' 26.56"   05.333 017 240 623    
 Saturn              346° 29' 52.517"   -00° 33' 24.77"   08.824 723 791 203    
 Uranus              125° 57' 53.781"   +00° 51' 35.57"   18.375 303 158 616    
 Neptune             292° 22' 51.322"   +00° 36' 22.92"   30.175 755 117 325    
 Pluto               342° 58' 34.931"   -13° 31' 27.11"   42.157 987 152 896    
 Moon (GEOCENTRIC)   213° 41' 32.318"   -05° 03' 55.44"   405045.155 Km         
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Julian Date Number (Terrestrial Time) : 625673.5 (BCE 3000/01/01 0 TDT)
 
 J2000 - Heliocentric geometric ecliptical coordinates. JPL DE431
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 Object              Longitude           Latitude         Distance from Sun(AU)      
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 Earth               146° 40' 43.261"   +00° 26' 05.92"   00.990 398 814 038    
 Mercury             306° 02' 35.719"   -06° 55' 51.41"   00.417 826 433 162    
 Venus               258° 27' 05.846"   +00° 41' 09.47"   00.727 621 125 931    
 Mars                068° 17' 04.436"   +00° 12' 28.92"   01.570 267 855 902    
 Jupiter             236° 55' 48.999"   +00° 53' 40.74"   05.329 824 265 309    
 Saturn              165° 01' 23.676"   +01° 24' 58.41"   09.591 437 769 666    
 Uranus              131° 29' 29.505"   +00° 45' 01.31"   18.447 900 672 633    
 Neptune             183° 27' 42.401"   +01° 22' 25.52"   30.246 943 791 572    
 Pluto               121° 12' 07.754"   +03° 12' 41.65"   39.049 533 184 482    
 Moon (GEOCENTRIC)   315° 04' 18.924"   -05° 31' 19.06"   405408.725 Km         
 -------------------------------------------------------------------------------
 
 J2000 - Heliocentric geometric ecliptical coordinates. JPL DE441
 -------------------------------------------------------------------------------
 Object              Longitude           Latitude         Distance from Sun(AU)      
 -------------------------------------------------------------------------------
 Earth               146° 40' 40.287"   +00° 26' 05.94"   00.990 398 575 288    
 Mercury             306° 02' 25.567"   -06° 55' 51.01"   00.417 830 386 108    
 Venus               258° 27' 01.189"   +00° 41' 09.74"   00.727 621 007 493    
 Mars                068° 17' 03.061"   +00° 12' 28.87"   01.570 266 992 746    
 Jupiter             236° 55' 49.350"   +00° 53' 40.72"   05.329 823 947 968    
 Saturn              165° 01' 23.624"   +01° 24' 58.40"   09.591 438 051 355    
 Uranus              131° 29' 34.459"   +00° 45' 01.36"   18.447 887 067 672    
 Neptune             183° 27' 52.749"   +01° 22' 25.68"   30.246 959 562 623    
 Pluto               121° 12' 04.565"   +03° 12' 39.60"   39.049 836 083 731    
 Moon (GEOCENTRIC)   314° 58' 03.026"   -05° 31' 21.24"   405410.378 Km         
 -------------------------------------------------------------------------------
 -------------------------------------------------------------------------------
 

Julian Date Number (Terrestrial Time) :  2440400.5 (CE 1969/06/28 0 TDT) - EPOCH 0 OF EPHEMERIDES
 
 J2000 - Heliocentric geometric ecliptical coordinates. JPL DE431
 -------------------------------------------------------------------------------
 Object              Longitude           Latitude         Distance from Sun(AU)      
 -------------------------------------------------------------------------------
 Earth               276° 33' 12.711"   -00° 00' 13.24"   01.016 588 581 772    
 Mercury             341° 41' 37.428"   -06° 26' 21.08"   00.378 693 572 382    
 Venus               326° 47' 41.351"   -03° 11' 28.55"   00.728 078 585 577    
 Mars                265° 30' 28.850"   -01° 05' 07.30"   01.464 628 015 906    
 Jupiter             188° 59' 38.259"   +01° 18' 16.07"   05.452 646 260 913    
 Saturn              031° 30' 27.757"   -02° 27' 50.69"   09.262 807 252 733    
 Uranus              183° 39' 10.308"   +00° 43' 42.72"   18.308 578 411 493    
 Neptune             238° 00' 21.168"   +01° 41' 57.54"   30.323 950 152 331    
 Pluto               174° 51' 28.132"   +15° 33' 33.37"   31.775 474 401 405    
 Moon (GEOCENTRIC)   250° 20' 35.517"   -04° 51' 22.86"   360708.962 Km         
 -------------------------------------------------------------------------------
 
 J2000 - Heliocentric geometric ecliptical coordinates. JPL DE441
 -------------------------------------------------------------------------------
 Object              Longitude           Latitude         Distance from Sun(AU)      
 -------------------------------------------------------------------------------
 Earth               276° 33' 12.711"   -00° 00' 13.24"   01.016 588 581 762    
 Mercury             341° 41' 37.428"   -06° 26' 21.08"   00.378 693 572 773    
 Venus               326° 47' 41.351"   -03° 11' 28.55"   00.728 078 585 578    
 Mars                265° 30' 28.850"   -01° 05' 07.30"   01.464 628 015 946    
 Jupiter             188° 59' 38.258"   +01° 18' 16.07"   05.452 646 260 197    
 Saturn              031° 30' 27.757"   -02° 27' 50.69"   09.262 807 248 583    
 Uranus              183° 39' 10.319"   +00° 43' 42.73"   18.308 579 401 971    
 Neptune             238° 00' 21.179"   +01° 41' 57.55"   30.323 952 396 873    
 Pluto               174° 51' 28.161"   +15° 33' 33.35"   31.775 473 135 178    
 Moon (GEOCENTRIC)   250° 20' 35.518"   -04° 51' 22.86"   360708.962 Km         
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 computed with Uruk_One

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