THE SNOW LINE in VISCOUS DISKS AROUND LOW-MASS STARS: IMPLICATIONS for WATER DELIVERY to TERRESTRIAL PLANETS in the HABITABLE ZONE

Gijs D. Mulders, Fred J. Ciesla, Michiel Min, Ilaria Pascucci

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

The water-ice or snow line is one of the key properties of protoplanetary disks that determines the water content of terrestrial planets in the habitable zone. Its location is determined by the properties of the star, the mass accretion rate through the disk, and the size distribution of dust suspended in the disk. We calculate the snow-line location from recent observations of mass accretion rates and as a function of stellar mass. By taking the observed dispersion in mass accretion rates as a measure of the dispersion in initial disk mass, we find that stars of a given mass will exhibit a range of snow-line locations. At a given age and stellar mass, the observed dispersion in mass accretion rates of 0.4 dex naturally leads to a dispersion in snow-line locations of ∼0.2 dex. For ISM-like dust sizes, the 1σ snow-line location among solar-mass stars of the same age ranges from ∼2 to ∼5 AU. For more realistic dust opacities that include larger grains, the snow line is located up to two times closer to the star. We use these locations and the outcome of N-body simulations to predict the amount of water delivered to terrestrial planets that formed in situ in the habitable zone. We find that the dispersion in snow-line locations leads to a large range in water content. For ISM-like dust sizes, a significant fraction of habitable-zone terrestrial planets around Sun-like stars remain dry, and no water is delivered to the habitable zones of low-mass M stars (<0.5 M<inf>⊙</inf>) as in previous works. The closer-in snow line in disks with larger grains enables water delivery to the habitable zone for a significant fraction of M stars and all FGK stars. Considering their larger numbers and higher planet occurrence, M stars may host most of the water-rich terrestrial planets in the galaxy if these planets are able to hold on to their water in their subsequent evolution.

Original languageEnglish (US)
Article number9
JournalAstrophysical Journal
Volume807
Issue number1
DOIs
StatePublished - Jul 1 2015

Fingerprint

snow
stars
terrestrial planets
planet
M stars
dust
water
accretion
stellar mass
moisture content
planets
water content
protoplanetary disks
opacity
delivery
sun
ice
occurrences
galaxies
rate

Keywords

  • planetary systems
  • planets and satellites: composition
  • planets and satellites: formation
  • protoplanetary disks
  • stars: low-mass

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

THE SNOW LINE in VISCOUS DISKS AROUND LOW-MASS STARS : IMPLICATIONS for WATER DELIVERY to TERRESTRIAL PLANETS in the HABITABLE ZONE. / Mulders, Gijs D.; Ciesla, Fred J.; Min, Michiel; Pascucci, Ilaria.

In: Astrophysical Journal, Vol. 807, No. 1, 9, 01.07.2015.

Research output: Contribution to journalArticle

@article{d38d9cb216304696a0e4134aaa7698a3,
title = "THE SNOW LINE in VISCOUS DISKS AROUND LOW-MASS STARS: IMPLICATIONS for WATER DELIVERY to TERRESTRIAL PLANETS in the HABITABLE ZONE",
abstract = "The water-ice or snow line is one of the key properties of protoplanetary disks that determines the water content of terrestrial planets in the habitable zone. Its location is determined by the properties of the star, the mass accretion rate through the disk, and the size distribution of dust suspended in the disk. We calculate the snow-line location from recent observations of mass accretion rates and as a function of stellar mass. By taking the observed dispersion in mass accretion rates as a measure of the dispersion in initial disk mass, we find that stars of a given mass will exhibit a range of snow-line locations. At a given age and stellar mass, the observed dispersion in mass accretion rates of 0.4 dex naturally leads to a dispersion in snow-line locations of ∼0.2 dex. For ISM-like dust sizes, the 1σ snow-line location among solar-mass stars of the same age ranges from ∼2 to ∼5 AU. For more realistic dust opacities that include larger grains, the snow line is located up to two times closer to the star. We use these locations and the outcome of N-body simulations to predict the amount of water delivered to terrestrial planets that formed in situ in the habitable zone. We find that the dispersion in snow-line locations leads to a large range in water content. For ISM-like dust sizes, a significant fraction of habitable-zone terrestrial planets around Sun-like stars remain dry, and no water is delivered to the habitable zones of low-mass M stars (<0.5 M⊙) as in previous works. The closer-in snow line in disks with larger grains enables water delivery to the habitable zone for a significant fraction of M stars and all FGK stars. Considering their larger numbers and higher planet occurrence, M stars may host most of the water-rich terrestrial planets in the galaxy if these planets are able to hold on to their water in their subsequent evolution.",
keywords = "planetary systems, planets and satellites: composition, planets and satellites: formation, protoplanetary disks, stars: low-mass",
author = "Mulders, {Gijs D.} and Ciesla, {Fred J.} and Michiel Min and Ilaria Pascucci",
year = "2015",
month = "7",
day = "1",
doi = "10.1088/0004-637X/807/1/9",
language = "English (US)",
volume = "807",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1",

}

TY - JOUR

T1 - THE SNOW LINE in VISCOUS DISKS AROUND LOW-MASS STARS

T2 - IMPLICATIONS for WATER DELIVERY to TERRESTRIAL PLANETS in the HABITABLE ZONE

AU - Mulders, Gijs D.

AU - Ciesla, Fred J.

AU - Min, Michiel

AU - Pascucci, Ilaria

PY - 2015/7/1

Y1 - 2015/7/1

N2 - The water-ice or snow line is one of the key properties of protoplanetary disks that determines the water content of terrestrial planets in the habitable zone. Its location is determined by the properties of the star, the mass accretion rate through the disk, and the size distribution of dust suspended in the disk. We calculate the snow-line location from recent observations of mass accretion rates and as a function of stellar mass. By taking the observed dispersion in mass accretion rates as a measure of the dispersion in initial disk mass, we find that stars of a given mass will exhibit a range of snow-line locations. At a given age and stellar mass, the observed dispersion in mass accretion rates of 0.4 dex naturally leads to a dispersion in snow-line locations of ∼0.2 dex. For ISM-like dust sizes, the 1σ snow-line location among solar-mass stars of the same age ranges from ∼2 to ∼5 AU. For more realistic dust opacities that include larger grains, the snow line is located up to two times closer to the star. We use these locations and the outcome of N-body simulations to predict the amount of water delivered to terrestrial planets that formed in situ in the habitable zone. We find that the dispersion in snow-line locations leads to a large range in water content. For ISM-like dust sizes, a significant fraction of habitable-zone terrestrial planets around Sun-like stars remain dry, and no water is delivered to the habitable zones of low-mass M stars (<0.5 M⊙) as in previous works. The closer-in snow line in disks with larger grains enables water delivery to the habitable zone for a significant fraction of M stars and all FGK stars. Considering their larger numbers and higher planet occurrence, M stars may host most of the water-rich terrestrial planets in the galaxy if these planets are able to hold on to their water in their subsequent evolution.

AB - The water-ice or snow line is one of the key properties of protoplanetary disks that determines the water content of terrestrial planets in the habitable zone. Its location is determined by the properties of the star, the mass accretion rate through the disk, and the size distribution of dust suspended in the disk. We calculate the snow-line location from recent observations of mass accretion rates and as a function of stellar mass. By taking the observed dispersion in mass accretion rates as a measure of the dispersion in initial disk mass, we find that stars of a given mass will exhibit a range of snow-line locations. At a given age and stellar mass, the observed dispersion in mass accretion rates of 0.4 dex naturally leads to a dispersion in snow-line locations of ∼0.2 dex. For ISM-like dust sizes, the 1σ snow-line location among solar-mass stars of the same age ranges from ∼2 to ∼5 AU. For more realistic dust opacities that include larger grains, the snow line is located up to two times closer to the star. We use these locations and the outcome of N-body simulations to predict the amount of water delivered to terrestrial planets that formed in situ in the habitable zone. We find that the dispersion in snow-line locations leads to a large range in water content. For ISM-like dust sizes, a significant fraction of habitable-zone terrestrial planets around Sun-like stars remain dry, and no water is delivered to the habitable zones of low-mass M stars (<0.5 M⊙) as in previous works. The closer-in snow line in disks with larger grains enables water delivery to the habitable zone for a significant fraction of M stars and all FGK stars. Considering their larger numbers and higher planet occurrence, M stars may host most of the water-rich terrestrial planets in the galaxy if these planets are able to hold on to their water in their subsequent evolution.

KW - planetary systems

KW - planets and satellites: composition

KW - planets and satellites: formation

KW - protoplanetary disks

KW - stars: low-mass

UR - http://www.scopus.com/inward/record.url?scp=84936157515&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84936157515&partnerID=8YFLogxK

U2 - 10.1088/0004-637X/807/1/9

DO - 10.1088/0004-637X/807/1/9

M3 - Article

AN - SCOPUS:84936157515

VL - 807

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

M1 - 9

ER -