The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory.


The Minor Planet Center is the official worldwide organization in charge of collecting observational data for minor planets (such as asteroids), calculating their orbits and publishing this information via the Minor Planet Circulars. Under the auspices of the International Astronomical Union (IAU), it operates at the Smithsonian Astrophysical Observatory, which is part of the Center for Astrophysics along with the Harvard College Observatory.[1]

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 to astrometric data, the MPC collects light curve photometry of minor planets. A key function of the MPC is helping observers coordinate follow up observations of possible near-Earth objects (NEOs) via its NEO web form and blog, the Near-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 (see Potentially hazardous objects and § Videos).[1]


The Minor Planet Center was set up at the University of Cincinnati in 1947, under the direction of Paul Herget.[4][5]: 63  Upon Herget's retirement on June 30, 1978,[5]: 67  the MPC was moved to the SAO, under the direction of Brian G. Marsden.[5]: 67  From 2006 to 2015,[6] the director of the MPC was Timothy Spahr,[7] who oversaw a staff of five. From 2015 to 2021, the Minor Planet Center was headed by interim director Matthew 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]


Periodical publications

"Minor Planet Circulars" and "Minor Planet Electronic Circulars" redirect here. For the publication by ALPO, see The Minor Planet Bulletin.

The MPC periodically releases astrometric observations of minor planets, as well as of comets and natural 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 1977 (MPC 4937–5016).[12]

Natural Satellites Ephemeris Service

The Natural 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]

See also


  1. ^ a b Centres: Minor Planet Center. International Astronomical Union. Retrieved 20 April 2016.
  2. ^ Marsden, B. G.; Williams, G. V. (February–March 1998). "The NEO Confirmation Page". Planetary and Space Science. 46 (2–3): 299. Bibcode:1998P&SS...46..299M. doi:10.1016/S0032-0633(96)00153-5.
  3. ^ "Real time reporting of NEOCP follow up". NEOCP Blog. Minor Planet Center. Archived from the original on 2016-04-13. Retrieved 20 April 2016.
  4. ^ Donald E. Osterbrock & P. Kenneth Seidelmann (1987). "Paul Herget: 1908–1981" (PDF). Biographical Memoirs of the National Academy of Sciences. Vol. 57. National Academies Press. pp. 64–65. ISBN 9780585272801. OCLC 45729798.
  5. ^ a b c Brian G. Marsden (July 1980). "The Minor Planet Center". Celestial Mechanics. 22 (1): 63–71. Bibcode:1980CeMec..22...63M. doi:10.1007/BF01228757. S2CID 119526916.
  6. ^ Galoche, J.L. (6 January 2015). "Minor Planet Center Director Steps Down". The Daily Minor Planet Blog. Minor Planet Center. Archived from the original on 2015-08-14. Retrieved 20 April 2016.
  7. ^ Gareth V. Williams (18 November 2010). "MPEC 2010-W10: Brian Marsden (1937 Aug. 5 – 2010 Nov. 18)". Minor Planet Electronic Circular.
  8. ^ Galoche, J.L. (4 February 2015). "Interim Director Appointed to the Minor Planet Center". The Daily Minor Planet Blog. Minor Planet Center. Archived from the original on 2015-05-26. Retrieved 1 December 2015.
  9. ^ "New acting MPC Director – MPEC 2021-D60". Minor Planet Electronic Circular. Minor Planet Center. 19 February 2021. Retrieved 22 February 2021.
  10. ^ "Staff – Matthew Payne, MPC Acting Director". Minor Planet Center. Retrieved 22 February 2021.
  11. ^ "MPC: Publications". Minor Planet Center. Retrieved 6 May 2016.
  12. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 6 May 2016.
  13. ^ "Division F Planetary Systems and Astrobiology". International Astronomical Union. Retrieved 2017-11-07.