The 3 Ks - Kuiper Belt, Koronis Asteroids & Karin Cluster

This article deals with three very interesting celestial objects that are not stars, planets or moons. To make things even more interesting, they all start on letter ‘K’, therefore, they can be referred to as the 3 Ks:

Kuiper belt. The term refers to a ring of various small celestial bodies in the Solar System beyond the orbit of the most distant planet Neptune. Just like the asteroid belt between the planets Mars and Jupiter, the Kuiper belt is mostly made up of asteroids which consist of metal and rock although the majority are made up of the so-called frozen volatiles or frozen water, ammonia or/and methane. However, the Kuiper belt is much larger than the asteroid belt. Also, there are other celestial bodies besides asteroids including all three dwarf planets that have been recognised as such (Pluto, Makemake and Haumea).

The Kuiper belt got its name after the renowned Dutch American astronomer and planetary scientist Gerard Kuiper (1905-1973). Although he didn’t formally discover this circumstellar disk in the most distant region of the Solar System, he played an important role in the modern planetary science. The Belt was discovered only in the 1980s, more than a decade after Kuiper’s death.

Koronis asteroids. Also known as the Koronian family or simply Koronis, the Koronis asteroids are one of the largest families of asteroids in the belt between the planets Mars and Jupiter. Consisting of approximately 300 asteroids with more or less the same chemical composition, the Koronis asteroids were created some two billions years ago following a collision of two larger celestial bodies. The largest asteroid in the Koronis family - 208 Lacrimosa is approximately 25 miles in diameter. Fewer than two dozens asteroids are 12 miles in diameter. The rest are smaller although varying greatly in size.
Karin cluster. A family of about 90 asteroids in the main-belt between Mars and Jupiter is actually a sub-group of the Koronis asteroids. Despite that, they are one of the most interesting asteroid families because a few years ago, astronomers used their orbits to calculate their common orbit which is de facto the orbit of the astronomical object from which they were formed. The cluster was called after the largest asteroid in the family - 832 Karin. Its diameter is approximately 12 miles.