Origin and Evolution of Long-period Comets

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F19%3A10405393" target="_blank" >RIV/00216208:11320/19:10405393 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=ApzCJ1Yktq" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=ApzCJ1Yktq</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/1538-3881/ab13aa" target="_blank" >10.3847/1538-3881/ab13aa</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Origin and Evolution of Long-period Comets

Popis výsledku v původním jazyce

We develop an evolutionary model of the long-period comet (LPC) population, starting from their birthplace in a massive trans-Neptunian disk that was dispersed by migrating giant planets. Most comets that remain bound to the solar system are stored in the Oort cloud. Galactic tides and passing stars make some of these bodies evolve into observable comets in the inner solar system. Our approach models each step in a full-fledged numerical framework. Subsequent analysis consists of applying plausible fading models and computing the original orbits to compare with observations. Our results match the observed semimajor axis distribution of LPCs when Whipple&apos;s power-law fading scheme with an exponent kappa = 0.6(-0.2)(+0.1) is adopted. The cumulative perihelion (q) distribution is well fit by a linear increase plus a weak quadratic term. Beyond q =15 au, however, the population increases steeply, and the isotropy of LPC orbital planes breaks. We find tentative evidence from the perihelion distribution of LPCs that the returning comets are depleted in supervolatiles and become active due to water ice sublimation for q &lt;= 3 au. Using an independent calibration of the population of the initial disk, our predicted LPC flux is smaller than observations suggest by a factor of similar or equal to 2. Current data only characterize comets from the outer Oort cloud (semimajor axes greater than or similar to 10(4) au). A true boost in understanding the Oort cloud&apos;s structure should result from future surveys when they detect LPCs with perihelia beyond 15 au. Our results provide observational predictions of what can be expected from these new data.

Název v anglickém jazyce

Origin and Evolution of Long-period Comets

Popis výsledku anglicky

We develop an evolutionary model of the long-period comet (LPC) population, starting from their birthplace in a massive trans-Neptunian disk that was dispersed by migrating giant planets. Most comets that remain bound to the solar system are stored in the Oort cloud. Galactic tides and passing stars make some of these bodies evolve into observable comets in the inner solar system. Our approach models each step in a full-fledged numerical framework. Subsequent analysis consists of applying plausible fading models and computing the original orbits to compare with observations. Our results match the observed semimajor axis distribution of LPCs when Whipple&apos;s power-law fading scheme with an exponent kappa = 0.6(-0.2)(+0.1) is adopted. The cumulative perihelion (q) distribution is well fit by a linear increase plus a weak quadratic term. Beyond q =15 au, however, the population increases steeply, and the isotropy of LPC orbital planes breaks. We find tentative evidence from the perihelion distribution of LPCs that the returning comets are depleted in supervolatiles and become active due to water ice sublimation for q &lt;= 3 au. Using an independent calibration of the population of the initial disk, our predicted LPC flux is smaller than observations suggest by a factor of similar or equal to 2. Current data only characterize comets from the outer Oort cloud (semimajor axes greater than or similar to 10(4) au). A true boost in understanding the Oort cloud&apos;s structure should result from future surveys when they detect LPCs with perihelia beyond 15 au. Our results provide observational predictions of what can be expected from these new data.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

<a href="/cs/project/GA18-06083S" target="_blank" >GA18-06083S: Vývoj pevných těles v protoplanetárních discích a během kolizí</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

The Astronomical Journal

ISSN

0004-6256

e-ISSN

—

Svazek periodika

157

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

27

Strana od-do

181

Kód UT WoS článku

000465597400001

EID výsledku v databázi Scopus

2-s2.0-85067380684