Formation of pebble-pile planetesimals and the internal structure of comets

Project: DissertationIndividual research project

Research areas and keywords

UKÄ subject classification

  • Astronomy, Astrophysics and Cosmology


  • Solar system, Planet formation, Comets, Numerical simulations


I investigate the formation process of planetesimals through the collapse of pebble clouds in protoplanetary disks. Massive clouds collapse fast and have fragmenting pebble-pebble collisions. The resulting planetesimal consists of both pebbles and dust, allowing the interior to be compact. Low-mass clouds collapse more slowly, only have bouncing collisions and result in a porous pebble-pile.

Layman's description

Planet formation occurs in protoplanetary disks of gas, dust and ice which orbit around newborn stars. Pebbles are thought to form through coagulation of dust grains in these disks. Such particles drift toward the star on short timescales because of gas drag. It has been proposed that hydrodynamical effects can form pebble clouds and that planetesimals form from the collapse of such clouds.
Effective start/end date2012/08/01 → …


Related projects

(Part of)

Anders Johansen, Chao-Chin Yang, Bertram Bitsch, Katrin Ros, Karl Wahlberg Jansson & Daniel Carrera

European Commission - FP7


Project: ResearchIndividual research project

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Related research output

Karl Wahlberg Jansson & Anders Johansen, 2014, In: Astronomy & Astrophysics. 570, A47.

Research output: Contribution to journalArticle

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