Critical-list minor planet

Summary

A critical-list minor planet (critical list numbered object or critical object) is a numbered minor planet for which existing measurements of the orbit and position are especially in need of improvement.[1]

The IAU's Minor Planet Center (MPC) regularly publishes a list of these critical objects in their Minor Planet Electronic Circular.[2] The list typically contains asteroids that have been observed at a small number of apparitions, especially on opposition, or that have not been adequately observed for more than 10 years, while other observatories create their own, customized lists.[3] The MPC also lists currently observable critical objects on their website,[4] providing differently formatted lists of orbital elements to the worldwide astrometric community.[5]

Lowell Observatory publishes their own critical list, distinctly different from the MPC, instead focusing on objects with high ephemeris uncertainty. Specifically, objects with computed ephemeris uncertainty greater than 2 arcseconds over the next 10 years, and objects whose orbits degrade significantly when temporally isolated observations are ignored, are included in the list.[3]

List edit

As of August 2023, the MPC includes 1,494 objects in their critical list. This list contains all critical objects within the first 50,000 numbered minor planets:[6]

See also edit

References edit

  1. ^ Monet, A. K. B. (December 1994). "CCD Astrometry of "Critical List" Minor Planets". American Astronomical Society Meeting Abstracts. 185: 43.11. Bibcode:1994AAS...185.4311M.
  2. ^ "Minor Planet Electronic Circulars – Sample MPECs". Minor Planet Center. Retrieved 4 July 2020.
  3. ^ a b "Critical Lists of Asteroids". Lowell Observatory. Retrieved 29 November 2023.
  4. ^ "Observable Critical-List Minor Planets". Minor Planet Center. Retrieved 4 July 2020.
  5. ^ "Orbital Elements: Critical-List Minor Planets". Minor Planet Center. Retrieved 4 July 2020.
  6. ^ "Data Available from the Minor Planet Center – MPCORB.DAT". Minor Planet Center. 26 June 2020. Retrieved 15 August 2023. (doc)

External links edit

  • MPEC 1998-G21 : CRITICAL-LIST MINOR PLANETS, Minor Planet Circular (1998)
  • Asteroid orbit determination using Bayesian probabilities, Karri Muinonen, Edward Bowell (1993)