The snow border

Marseille, M.; Cazaux, S.

doi:10.1051/0004-6361/200913960

Cited by 8 publications

(7 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sack & Baragiola 1993; Brown & Bolina 2007) but condensation is less well understood. Marseille & Cazaux (2011) find that there is an extended region beyond the snow line where both icy and bare grains coexist, for a radial distance of about 0.4 au. This should be investigated further in future work with a disc model that tracks the evolution of the water.…”

Section: Discussionmentioning

confidence: 78%

On the evolution of the snow line in protoplanetary discs

Martin

Livio

2012

Monthly Notices of the Royal Astronomical Society: Letters

145

View full text Add to dashboard Cite

We model the evolution of the snow line in a protoplanetary disc. If the magnetorotational instability (MRI) drives turbulence throughout the disc, there is a unique snow line outside of which the disc is icy. The snow line moves closer to the star as the infall accretion rate drops. Because the snow line moves inside the radius of the Earth's orbit, the formation of our water-devoid planet is difficult with this model. However, protoplanetary discs are not likely to be sufficiently ionized to be fully turbulent. A dead zone at the mid-plane slows the flow of material through the disc and a steady state cannot be achieved. We therefore model the evolution of the snow line also in a time-dependent disc with a dead zone. As the mass is accumulating, the outer parts of the dead zone become self-gravitating, heat the massive disc and thus the outer snow line does not come inside the radius of the Earth's orbit, contrary to the fully turbulent disc model. There is a second, inner icy region, within the dead zone, that moves inwards of the Earth's orbit after a time of about 10 6 yr. With this model there is sufficient time and mass in the disc for the Earth to form from water-devoid planetesimals at a radius of 1 au. Furthermore, the additional inner icy region predicted by this model may allow for the formation of giant planets close to their host star without the need for much migration.

show abstract

Section: Discussionmentioning

confidence: 78%

On the evolution of the snow line in protoplanetary discs

Martin

Livio

2012

Monthly Notices of the Royal Astronomical Society: Letters

145

View full text Add to dashboard Cite

show abstract

“…Lecar et al 2006). Marseille & Cazaux (2011) find that there is an extended region down to almost 100 K, the snow border, in which both icy and dry planetesimals can coexist. Particles migrating through the disc accumulate near the snow line over a short radial extent and grow through collision (Kretke & Lin 2007).…”

Section: Theoretical Models Of the Snow Linementioning

confidence: 96%

On the formation and evolution of asteroid belts and their potential significance for life

Martin

Livio

2012

Monthly Notices of the Royal Astronomical Society: Letters

View full text Add to dashboard Cite

Suggestions have been made that asteroid belts may be important both for the existence of life and perhaps even for the evolution of complex life on a planet. Using numerical models for protoplanetary discs we calculate the location of the snow line, and we propose that asteroid belts are most likely to form in its vicinity. We then show that observations of warm dust in exo-solar systems, thought to be produced by collisions between asteroids in a belt, indicate that asteroid belts (when they exist), indeed coincide with the radial location and the temperature of the snow line. Giant planets form outside the snow line and prevent planet formation just inside of their orbit creating an asteroid belt there. However, the migration of giant planets through the asteroid belt likely disperses the compact formation. We examine existing observations of giant exo-planets and find that less than 4% are at radial locations outside of the snow line. This definitely may be the consequence of observational selection effects. However, with this caveat in mind, we point out that the dearth of giant planets outside the snow line may also suggest that compact asteroid belts are not common, and more speculatively that complex life may not expected in most of the currently observed systems.

show abstract

“…Marseille and Cazaux 150 constructed a water-accretion model where water molecules are physisorbed on carbonaceous grains and can cluster together, leading to a stronger binding, with a maximum of six water neighbors. Time scales for condensation of water ice below 100 K were determined in this way, and these were found to be rather long compared to time scales of grain mixing, caused by turbulence and infall.…”

Section: Applications Of the Kmc Technique To Astrochemistrymentioning

confidence: 99%