• Processing (Info)
  • 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.
      • Once a page has been placed on your site, you can forget about it. You do not need to update the page as orbits are improved or as objects are identified or numbered--this is all handled transparently by this service. You need only modify the page as you discover new objects.
    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 (ground-based only) 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.