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Infalling Planetesimals in Pre-Main Sequence Stellar SystemsThese are exciting times in the study of planetary system formation with a steadily expanding inventory of exo-planet detections, and imaging of dust disks around nearby young and main sequence stars. While these discoveries imply that our Solar System is far from unique, linking the data for the protoplanetary and debris disks to mature planetary systems requires a demonstration that disk evolution proceeds via planetesimal production and growth to the formation of planets. Theoretical studies of planet formation indicate that planetesimals grow, via runaway accretion, to lunar-sized (approx. = 2000 km) embryos in 10(exp 5) years. Recent gas giant planet formation studies have suggested that most of the action in planet formation occurs over 1-16 Myr, with formation of planets similar to Jupiter in t less than 10 Myr, within the time interval that infrared (IR) and optical emission line studies have demonstrated that circumstellar material remains detectable around both solar mass and intermediate mass stars. Direct imaging of exo-planetesimals is not feasible with current and foreseeable technology, since such bodies have substantially less surface area than micron-sized grains distributed in a disk, and thus are inefficient IR emitters. However, such bodies may be indirectly detectable.
Document ID
19990064009
Acquisition Source
Jet Propulsion Laboratory
Document Type
Other
Authors
Grady, Carol A.
(Eureka Scientific, Inc. Oakland, CA United States)
Sitko, Michael L.
(Cincinnati Univ.)
Russell, Ray W.
(Aerospace Corp.)
Lynch, David K.
(Aerospace Corp.)
Hanner, Martha S.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA United States)
Perez, Mario R.
(Space Applications Corp.)
Bjorkman, Karen S.
(Toledo, Univ.)
DeWinter, Dolf
Date Acquired
August 19, 2013
Publication Date
January 1, 1999
Subject Category
Astrophysics
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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