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Seminar Detail
The Effect of Protoplanetary Disk Dispersal on Planet Formation
Presenter: David Hollenbach (NASA Ames Research Center)
February 4, 2008 11:00 AM Pacific
One of the first questions facing astrobiologists is: "What is the likelihood of habitable planets or moons forming around stars in the universe?" During their formation from gas and dust orbiting young stars, planets compete with mechanisms that disperse the gas and dust: viscous accretion on the central star and dispersal into interstellar space by the effects of nearby stellar encounters, the winds from the central star, and the ultraviolet (UV) and X-ray photons from either the central star or nearby luminous stars. We show with theoretical models validated by astronomical observations how viscous accretion likely dominates the dispersal in the inner regions (< 1 AU) of protoplanetary disks, while UV-induced photoevaporation dominates in the outer regions. These dispersal mechanisms may prevent, truncate, or otherwise affect planet formation and the resultant planetary architecture. Planetary formation is most seriously affected around high mass stars and around low mass stars in clusters of stars with high mass star members. We review progress made on answering the above question and future prospects.
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The Director’s Seminar series features talks from scientists who are invited by the NAI Director to present their research results to the community. A primary goal of the seminars is to encourage interdisciplinary collaboration across NAI teams and within the astrobiology community at large.
Team Overview Seminars describe the work of the fourteen NAI teams and NAI Central. They offer an opportunity to find out more about the science, E/PO and other activities being performed by the NAI teams and the NAI Central office.
The Forum for Astrobiology Research (FAR) provides an opportunity for graduate students to present their research results and to meet as a student community for networking and mutual support.
The University of Washington seminar series is hosted by the NAI Virtual Planetary Lab (VPL) team from the UW campus in Seattle.
