Critical-list minor planet

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.

The IAU's Minor Planet Center (MPC) regularly publishes a list of these critical objects in their Minor Planet Electronic Circular. 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. The MPC also lists currently observable critical objects on their website, providing differently formatted lists of orbital elements to the worldwide astrometric community.

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.

List
, the MPC includes 1,494 objects in their critical list. This list contains all critical objects within the first 50,000 numbered minor planets:


 * 1915 Quetzálcoatl
 * 3362 Khufu
 * 5335 Damocles
 * 5381 Sekhmet
 * (5590) 1990 VA
 * 6489 Golevka
 * 7066 Nessus
 * (7236) 1987 PA
 * 10370 Hylonome
 * (15788) 1993 SB
 * (15809) 1994 JS
 * 19521 Chaos
 * 20461 Dioretsa
 * 28978 Ixion
 * 38083 Rhadamanthus
 * 49036 Pelion
 * 19521 Chaos
 * 20461 Dioretsa
 * 28978 Ixion
 * 38083 Rhadamanthus
 * 49036 Pelion
 * 20461 Dioretsa
 * 28978 Ixion
 * 38083 Rhadamanthus
 * 49036 Pelion
 * 28978 Ixion
 * 38083 Rhadamanthus
 * 49036 Pelion
 * 38083 Rhadamanthus
 * 49036 Pelion
 * 38083 Rhadamanthus
 * 49036 Pelion
 * 49036 Pelion
 * 49036 Pelion
 * 49036 Pelion