Neptune Ephemeris Generator Help

This form enables you to generate a table listing useful information about the viewing geometry for Neptune and/or any of its moons as a function of time. You are free to specify which of a variety of useful quantities to tabulate. The file returned will contain a single header line describing each column, followed by one row of numbers for each time step.

Change History

1.0 (February 3, 1997): Original Neptune Ephemeris Generator on line.
1.1 (February 6, 1997): Added optional columns for sub-solar and sub-Earth inertial longitudes.
2.0 (January 12, 1999): Added sub-solar and sub-Earth latitude/rotating longitude options. Revised user interface. Extended ephemeris time limits.
2.1 (February 1, 1999): Added a new ephemeris option.
2.2 (January 10, 2003): Added a new column option providing second accuracy in time tags.
2.3 (December 1, 2009): Updated the default ephemerides. To reduce confusion, we have removed the choice about what ephemeris to use.
2.5 (January 23, 2013): Raised the maximum number of output lines to 10,000. Renumbered for consistency across all the Ephemeris Generator tools. Ephemeris updates.
2.5.1 (February 28, 2014): Added S/2004 N 1.
2.6 (January 4, 2016): Ported to new server. Ephemeris updates.
2.7 (October 14, 2020): Ephemeris updates, updated name of "Hippocamp".
2.8 (June 20, 2021): Ephemeris updates.

Time Limits

The start and stop times (UTC) of the table can be entered in a variety of formats. For example, the following all parse to 0:01:02 UTC on July 4, 1976: If you want the gory details of how times are interpreted, click here.

Enter the time interval to be used for the tabulation as a number in the box, and select the time unit from the choices provided.

General Column Selection

Click on the box to the left of each quantity or set of quantities that you wish to tabulate. The order of the columns in the table will match the order listed on the form. Possible selections are as follows:

Moon Columns

You may also include the positions of any set of Neptune's moons in the table. Up to four pairs of quantities can be tabulated for each selected moon:

Finally, click on the box to the left of each moon that you wish to include in the table. Note that it is not necessary to include any moon columns at all.

Neptune Ephemeris Generator Form | Node Tools | Ring-Moon Systems Node Home

Last updated June 20, 2021.

Mark Showalter