Planetesimal

Planetesimals are small, solid objects thought to exist in protoplanetary disks around a young or forming star. Planetesimals are created when dust particles collide.

Planetesimal Media

Debris disks detected in HST archival images of young stars, HD 141943 and HD 191089, using improved imaging processes (24 April 2014).
486958 Arrokoth, the first pristine planetesimal visited by a spacecraft.

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