The MPC runs a number of free online services for observers to assist them in observing minor planets and comets. The complete catalogue of minor planet orbits (sometimes referred to as the "Minor Planet Catalogue") may also be freely downloaded. In addition toastrometric data, the MPC collects light curve photometry of minor planets. A key function of the MPC is helping observers coordinate follow up observations of possiblenear-Earth objects (NEOs) via its NEO web form and blog, theNear-Earth Object Confirmation Page.[2][3] The MPC is also responsible for identifying, and alerting to, new NEOs with a risk of impacting Earth in the few weeks following their discovery(seePotentially hazardous objects and§ Videos).[1]
The Minor Planet Center was set up at theUniversity of Cincinnati in 1947, under the direction ofPaul Herget.[4][5]: 63 Upon Herget's retirement on June 30, 1978,[5]: 67 the MPC was moved to the Smithsonian Astrophysical Observatory, under the direction ofBrian G. Marsden.[5]: 67 From 2006 to 2015,[6] the director of the MPC wasTimothy Spahr,[7] who oversaw a staff of five. From 2015 to 2021, the Minor Planet Center was headed by interim directorMatthew Holman.[8] Under his leadership, the MPC experienced a significant period of reorganization and growth, doubling both its staff size and the volume of observations processed per year. Upon Holman's resignation on February 9, 2021 (announced on February 19, 2021) Matthew Payne became acting director of the MPC.[9][10]
"Minor Planet Circulars" and "Minor Planet Electronic Circulars" redirect here. For the publication byALPO, seeThe Minor Planet Bulletin.
The MPC periodically releasesastrometric observations of minor planets, as well as ofcomets andnatural satellites. These publications are the Minor Planet Circulars (MPCs), the Minor Planet Electronic Circulars (MPECs), and the Minor Planet Supplements (MPSs and MPOs).[11] An extensive archive of publications in a PDF format is available at the Minor Planet Center's website. The archive's oldest publication dates back to 1 November 1979 (MPC 4937–5016).[12]
Minor Planet Circulars (M.P.C. orMPCs), established 1947, is ascientific journal that is generally published by the Minor Planet Center on the date of eachfull moon, when the number of reported observations are minimal due to the brighter night sky. TheCirculars contain astrometric observations, orbits and ephemerides of minor planets, comets and certain natural satellites. The astrometric observations of comets are published in full, while the minor planet observations are summarised by observatory code (the full observations now being given in theMinor Planet Circulars Supplement). New numberings and namings of minor planets(also seeNaming of Minor Planets), as well as numberings of periodic comets and natural satellites, are announced in theCirculars. New orbits for comets and natural satellites appear in theCirculars; new orbits for minor planets appear in the Minor Planets and Comets Orbit Supplement(see below).
TheMinor Planet Electronic Circulars (MPECs) are published by the Minor Planet Center. They generally containpositional observations andorbits ofunusual minor planets and allcomets. Monthly lists of observable unusual objects, observable distant objects, observable comets and thecritical list of numbered minor planets also appear on these circulars. Daily Orbit Update MPECs, issued every day, contain new identifications and orbits of minor planets, obtained over the previous 24 hours.
TheMinor Planets and Comets Supplement (MPS) is published on behalf ofIAU's Division F (Planetary Systems and Bioastronomy)[13] by the Minor Planet Center.
TheMinor Planets and Comets Orbit Supplement (MPO) is published on behalf of IAU's Division F by the Minor Planet Center.
TheNatural Satellites Ephemeris Service is an online service of the Minor Planet Center. The service provides "ephemerides, orbital elements and residual blocks for the outer irregular satellites of the giant planets".[1]
