167P/CINEOS

The comet nucleus (~66 km) is roughly half the size of C/2014 UN271 (Bernardinelli–Bernstein) and it has a similar perihelion point just outside the orbit of Saturn.

Description

Due to its high Jupiter tisserand of 3.5, and a semi-major axis larger than that of Jupiter, 167P/CINEOS is classified as a Chiron-type comet, named after the groups namesake, 2060 Chiron or 95P/Chiron, designated as both minor planet and comet.

167P/CINEOS was first reported as a minor planet, designated 2004 PY₄₂, but was found to have a very faint asymmetric cometary coma. Contrary to Chiron, which is the prototype object for the dynamical group of centaurs, 167P/CINEOS has no "dual status" as comet and minor planet, and demonstrates the inconsistencies in applying the current rules for designating small Solar System bodies. 167P/CINEOS not only has orbital parameters similar to those of Chiron, but also a low B–R magnitude of 1.29±0.03, which places it into the group grey centaurs.

In June 2039, 167P/CINEOS will pass 1.64 AU from Uranus.