rubblepile

A rubblepile is a celestial body composed of loosely aggregated fragments of rock and ice. These objects are typically irregular in shape and lack a significant gravitational pull to form a spherical body. They are often found in the outer solar system, particularly as comets or their remnants. When a comet approaches the Sun, its icy components sublimate, leaving behind a trail of dust and debris that can coalesce into a rubblepile structure. These structures can be quite fragile and are prone to breaking apart under tidal forces or impacts. Asteroids can also exist as rubblepiles, formed from the collision and gravitational reaccumulation of smaller bodies. The internal structure of a rubblepile is characterized by voids between the constituent fragments, distinguishing it from a solid, monolithic object. Understanding rubblepile composition and structure is important for planetary science, particularly in the study of asteroid and comet evolution, and for assessing potential impact hazards.