Editing Asteroid (section)

== Formation ==
{{Main|Origin of the asteroid belt}}
Many asteroids are the shattered remnants of [[planetesimal]]s, bodies within the young Sun's [[solar nebula]] that never grew large enough to become [[planet]]s.<ref name=CNEOS-FAQ/> It is thought that planetesimals in the asteroid belt evolved much like the rest of objects in the solar nebula until Jupiter neared its current mass, at which point excitation from [[orbital resonance]]s with Jupiter ejected over 99% of planetesimals in the belt. Simulations and a discontinuity in spin rate and spectral properties suggest that asteroids larger than approximately {{cvt|120|km|0}} in diameter [[Accretion (astrophysics)|accreted]] during that early era, whereas smaller bodies are fragments from collisions between asteroids during or after the Jovian disruption.<ref>{{cite journal |last1=Bottke | first1=William F. Jr. |last2=Durda |first2=Daniel D. |last3=Nesvorny |first3=David |last4=Jedicke |first4=Robert |last5=Morbidelli |first5=Alessandro |last6=Vokrouhlicky |first6=David |last7=Levison |first7=Hal |year=2005 |title=The fossilized size distribution of the main asteroid belt |journal=Icarus |volume=175 |issue=1 |page=111 |doi=10.1016/j.icarus.2004.10.026 |bibcode=2005Icar..175..111B |url=http://astro.mff.cuni.cz/davok/papers/fossil05.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://astro.mff.cuni.cz/davok/papers/fossil05.pdf |archive-date=2022-10-09 |url-status=live}}</ref> Ceres and Vesta grew large enough to melt and [[Planetary differentiation|differentiate]], with heavy metallic elements sinking to the core, leaving rocky minerals in the crust.<ref name=ACM>{{cite book |title=Asteroids, Comets, and Meteors |last=Kerrod |first=Robin |year=2000 |publisher=Lerner Publications Co. |isbn=978-0-585-31763-2 |url-access=registration |url=https://archive.org/details/asteroidscometsm00robi}}</ref>

In the [[Nice model]], many [[Kuiper belt|Kuiper-belt objects]] are captured in the outer asteroid belt, at distances greater than 2.6&nbsp;AU. Most were later ejected by Jupiter, but those that remained may be the [[D-type asteroid]]s, and possibly include Ceres.<ref>{{cite journal |last1=McKinnon |first1=William |first2=B. |last2=McKinnon |year=2008 |title=On The Possibility of Large KBOs Being Injected into The Outer Asteroid Belt |journal=Bulletin of the American Astronomical Society |volume=40 |page=464 |bibcode=2008DPS....40.3803M}}</ref>