The physics and evolution of small molecular clouds in nebulæ : globulettes as seeds for planets?

• Main Author: Dittrich, Karsten
• Format: Others
• Language: English
• Published: 2010
• Subjects: Physics Chemistry Maths; free-floating planets - H II regions - ISM: individual: Carina Nebula; Rosette Nebula - ISM: globules; globulettes - planet capturing; Fysik; Kemi; Matematik
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-45560

Globulettes have recently been found in the Rosette Nebula, the Carina Nebula and other nebulæ. They are expected to be seeds of brown dwarfs and free-floating planetary-mass objects. The size distribution in the Carina Nebula was found to follow a power-law, and the same power-function resulted in 880 +- 250 globulettes in total in the Rosette Nebula. Compared to the 145 observed objects in this nebula, many globulettes are beneath the resolution limit of the Nordic Optical Telescope, which was used to explore the Rosette Nebula. A simulation that arranged all these globulettes randomly in the nebula determined that some globulettes are captured by stars. They are believed to form into one or more planets, orbiting the star thereafter. The possibility that globulettes result into the formation of planets, orbiting a star, is some 4.75·10^2 per cent. According to this simulation, about 3.35·10^3 per cent of the stars with spectral type A to M host one or more planets that once have been globulettes. === <p>Validerat; 20101217 (root)</p>