IAU Minor Planet Center
Ephemeris plotting

Related links:

• Lowell Observatory Ephemeris plotting in TheSky

• Lowell Observatory - source of orbital elements "ASTORB.DAT"

• Minor Planet Center source of current orbital elements "MPCORB.DAT"

• Minor Planet Center NEO Confirmation Page

Index

• Enabling Object Type "Reference Point"
• Labeling the data
       Enabling Extended Labels - Needed to label data
• Lowell Observatory Asteroid Ephemeris (ASTEPH) page
• Searching the data
• The HEADER  used to define the data fields automatically!

Background

NOTE: Usually the preferred method for using Minor Planets is to have TheSky compute the minor planet positions by numerically integrated the positions to a high degree of accuracy. This also allows TheSky to compute accurate tracking rates in real time. This is much more flexible, definitely easier, and less prone to error. The only requirement is an up to date accurate set of orbital elements.  An ephemeris is only needed for objects that do not have reasonably established orbits, where the currently supplied orbital elements are not accurate, or where no orbital elements currently available.

The HEADER used to define the data fields
allows for compiling automatically

>SEARCH 1,17
>RAHOURS 19,20
>RAMINUTES 22,23
>RASECONDS 25,29
>SEARCH 1,18
>DECSIGN 30,30
>DECDEGREES 31,32
>DECMINUTES 34,35
>DECSECONDS 37,38
>MAGNITUDE 69,73
>OBJECT TYPE 55
>LOADMEMORY
>IDENTIFIER MPC Ephemeris
>PARSE "Date / Time (UT)" 1,17
>PARSE "Delta." 40,46
>PARSE "r" 48,54
>PARSE "El." 56,61
>PARSE "Ph." 63,67
>PARSE "Sky Motion arcsecond/min" 76,82
>PARSE "P.A." 85, 90
>PARSE "Alt. Az." 94,103

To "grab" the text from the Minor Planet Center Ephemeris service page drag the mouse by holding down the left mouse button over the text as shown below then right mouse click to COPY the text to the clipboard.

Ate 111 Ephemeris example from the Minor Planet Center Ephemeris

Right Mouse Click and Choose COPY

Then simply add the following header to the text data (using WordPad/NotePad or equivalent so the data can be directly compiled, labeled, searched, and plotted in TheSky.

>SEARCH 1,17
>RAHOURS 19,20
>RAMINUTES 22,23
>RASECONDS 25,29
>SEARCH 1,18
>DECSIGN 30,30
>DECDEGREES 31,32
>DECMINUTES 34,35
>DECSECONDS 37,38
>MAGNITUDE 69,73
>OBJECT TYPE 55
>LOADMEMORY
>IDENTIFIER MPC Ephemeris
>PARSE "Date / Time (UT)" 1,17
>PARSE "Delta." 40,46
>PARSE "r" 48,54
>PARSE "El." 56,61
>PARSE "Ph." 63,67
>PARSE "Sky Motion arcsecond/min" 76,82
>PARSE "P.A." 85, 90
>PARSE "Alt. Az." 94,103

;00111 <- Ate 111 example NOTE the ";" semi colon comments a line that is not data!
;
Date       UT      R.A. (J2000) Decl.    Delta     r     El.    Ph.   V      Sky Motion        Object    Sun   Moon
            h m s                                                            "/min    P.A.    Azi. Alt.  Alt.  Phase Dist. Alt.
2008 01 30 000000 19 50 19.3 -22 00 25   3.805   2.859   14.0   4.8  13.6    1.00    077.6    066  -06   +06   0.52   078  -64
2008 01 30 020000 19 50 27.7 -21 59 59   3.804   2.859   14.0   4.8  13.6    1.00    077.6    084  -28   -15   0.51   077  -66
2008 01 30 040000 19 50 36.2 -21 59 33   3.804   2.859   14.1   4.8  13.6    1.01    077.7    105  -51   -38   0.50   076  -48
2008 01 30 060000 19 50 44.7 -21 59 08   3.804   2.859   14.1   4.8  13.6    1.01    077.8    150  -69   -59   0.50   075  -27
... and so on

Save the new text file with data and header then use the Database Compiler to create the SDB file. That is Data | Import then Browse for the text file. Then compile the SDB.