|Ephemeris Interploation and exposure calculation Visual Basic program (EphInterpolator)
This allows positions to be worked out quickly and easily from an
ephemeris. It was originally intended for when orbital elements were not
readily obtainable (e.g. objects still on the NEOCP) so that accurate
telescope pointing and rate of motion could be achieved. However, it is now used for all ephemeris work at the telescope and
also when reducing measures with Astrometrica, to accurately interpolate between ephemeris intervals.
The MPES button will retrieve an ephemeris from the Minor Planet
Center for a target named in the Object box. A drop-down list of objects
on the NEOCP allows an ephemeris for an individual NEOCP object to be
retrieved, alternatively ephemerides for all NEOCP objects can be
retrieved that match the NEO rating and class parameters if the Object
box is left empty. Variant orbits from the MPES or NEOCP can also be
Pressing the Calculate button works out the RA, Dec, Speed and
PA of motion using a second order interpolation method for the specified
A separate 'pad' can be undocked from the main form (visible to the
right in the screen shot above) which is set to be an 'always on
top' window for ease of use when transferring values into other software.
Pressing the blue "Astrometrica" button sends the calculated Speed
and PA to Astrometrica and initiates the completion of the Astrometrica
"Stack Images" function.