2006/02/09 by M. Lecar, M. Podolak, Dimitar Sasselov +3 · 4 citations
Physics and Astronomy · #Accretion (finance) #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Geometry #Line (geometry) #Mars Exploration Program #Meteorology #Opacity #Physics #Planet #Planetesimal #Protoplanet #Protoplanetary disk #Saturn #Snow #Snow line #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/500287
published as Astrophys.J. 640 (2006) 1115-1118 · Accepted for publication in ApJ, 9 pages, 4 figures
arxiv created 2006/02/09 · openalex publication_date 2006/03/27 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In a protoplanetary disk, the inner edge of the region where the temperature falls below the condensation temperature of water is referred to as the snow line. Outside the snow line, water ice increases the surface density of solids by a factor of 4. The mass of the fastest growing planetesimal (the isolation mass) scales as the surface density to the 3/2 power. It is thought that ice-enhanced surface densities are required to make the cores of the gas giants (Jupiter and Saturn) before the disk gas dissipates. Observations of our solar system's asteroid belt suggest that the snow line occurred near 2.7 AU. In this paper we revisit the theoretical determination of the snow line. In a minimum-mass disk characterized by conventional opacities and a mass accretion rate of 10 -8 M ☉ yr -1 , the snow line lies at 1.6-1.8 AU, just past the orbit of Mars. The minimum-mass disk, with a mass of 0.02 M ☉ , has a lifetime of 2 million years with the assumed accretion rate. Moving the snow line past 2.7 AU requires that we increase the disk opacity, accretion rate, and/or disk mass by factors ranging up to an order of magnitude above our assumed baseline values.