Minor Planet & Comet Ephemeris Service

This webpage serves three purposes:
  1. To allow an observer to get ephemerides (utilizing the latest published elements) and/or elements for an arbitrary set of (up to 100 at a time) minor planets or comets.
  2. To allow an observer to check the current observability of an arbitrary set of (up to 100 at a time) minor planets, then to get ephemerides and/or elements for those deemed to be observable.
  3. To allow an observer to prepare an HTML document that can be placed on their own website, with the aim of encouraging others to perform follow-up astrometry of their minor planet discoveries. Of course, this facility can also be used to generate a page for any arbitrary set of minor planets.
In either case, enter your list of desired objects in the text-area indicated. By default, ephemerides will be returned. If you desire a HTML document to be returned, check the appropriate box. Further options, specific to each purpose are accessible further down this page.

A PDF document (633 KB) describing the use of the MPES is available. (Updated 2011 Jan. 14)

Information on any known problems with this service is available.

Report a problem. Comment on this service.

Why can't I find an object with a particular name? (Added 2004 Sept. 7)


Return ephemerides Return summary Return HTML page

Objects may be identified by designation or by name. Enter a list of designations or names below (one entry per line, excess entries will be ignored):


Ephemeris Options (applicable only if selecting ephemeris return):

By default, ephemerides are geocentric, begin now and are for 20 days at 1 day intervals.

Ephemeris start date: Number of dates to output

Ephemeris interval: Ephemeris units: days hours minutes seconds

For daily ephemerides, enter desired offset from 0h UT: hours

You may enter an observatory code or your observing site's coordinates:

Observatory code:

Longitude ° E, latitude °, altitude m.

Longitudes and latitudes should be entered in decimal degrees.

Display R.A./Decl. positions in: truncated sexagesimal or full sexagesimal or decimal units
heliocentric position vector heliocentric position/velocity vector
geocentric position vector

Total motion and direction
Separate R.A. and Decl. coordinate motions
Separate R.A. and Decl. sky motions
Display motions as: "/sec "/min "/hr °/day

Suppress output if sun above local horizon

Suppress output if object below local horizon

Output data for photometric reductions

Generate perturbed ephemerides for unperturbed orbits

Measure azimuths:
westwards from the south meridian
eastwards from the north meridian

Also display elements for epoch

Format for elements output:

none MPC 1-line MPC 8-line
SkyMap (SkyMap Software) Guide (Project Pluto) xephem (E. Downey)
Home Planet (J. Walker) MyStars! (Relative Data Products) TheSky (Software Bisque)
Starry Night (Sienna Software) Deep Space (D. S. Chandler) PC-TCS (D. Harvey)
Earth Centered Universe (Nova Astronomics) Dance of the Planets (ARC) MegaStar V4.x (E.L.B. Software)
SkyChart 2000.0 (Southern Stars Software) Voyager II (Carina Software) SkyTools (CapellaSoft)
Autostar (Meade Instruments)

If you select 8-line MPC format, you may display the residual block for the objects selected:

Show residuals blocks. Show only residual lines containing observations from code .

If you select 8-line MPC format the elements will be displayed with the ephemerides. If you select any format other than MPC format only the elements are returned. In such instances, your browser should download the elements file then save it to your local disk.



HTML Document Options (applicable only if selecting HTML return):

Both these are optional. A default will be supplied for the title.

The default base URL is null.

Title for document:

Base URL for document:

All objects should be selected or unselected by default.

Lists of objects and software types should be centered or uncentered.

Return list of objects or link to summary page.

Note that the returned document will require you to add some introductory remarks. Default text for this is supplied, but should be replaced.