Abstract:
:beta Pictoris (beta Pic) is a main-sequence star with an edge-on dust disk that might represent a state of the early Solar System. The dust does not seem to be a remnant from the original protoplanetary disk, but rather is thought to have been generated from large bodies like planetesimals and/or comets. The history and composition of the parent bodies can therefore be revealed by determining the spatial distribution, grain size, composition and crystallinity of the dust through high-resolution mid-infrared observations. Here we report that the sub-micrometre amorphous silicate grains around beta Pic have peaks in their distribution around 6, 16 and 30 au (1 au is the Sun-Earth distance), whereas the crystalline and micrometre-sized amorphous silicate grains are concentrated in the disk centre. As sub-micrometre grains are blown quickly out from the system by radiation pressure from the central star, the peaks indicate the locations of ongoing dust replenishment, which originates from ring-like distributions of planetesimals or 'planetesimal belts'.
journal_name
Naturejournal_title
Natureauthors
Okamoto YK,Kataza H,Honda M,Yamashita T,Onaka T,Watanabe J,Miyata T,Sako S,Fujiyoshi T,Sakon Idoi
10.1038/nature02948keywords:
subject
Has Abstractpub_date
2004-10-07 00:00:00pages
660-3issue
7009eissn
0028-0836issn
1476-4687pii
nature02948journal_volume
431pub_type
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