Meteoroid Impacts as a Source of Bennu's Particle Ejection Events

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F20%3A10423527" target="_blank" >RIV/00216208:11320/20:10423527 - isvavai.cz</a>

Výsledek na webu

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

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2019JE006282" target="_blank" >10.1029/2019JE006282</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Meteoroid Impacts as a Source of Bennu's Particle Ejection Events

Popis výsledku v původním jazyce

Asteroid (101955) Bennu, a near-Earth object with a primitive carbonaceous chondrite-like composition, was observed by the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft to undergo multiple particle ejection events near perihelion between December 2018 and February 2019. The three largest events observed during this period, which all occurred 3.5 to 6 hr after local noon, placed numerous particles &lt;10 cm on temporary orbits around Bennu. Here we examine whether these events could have been produced by sporadic meteoroid impacts using the National Aeronautics and Space Administration&apos;s (NASA) Meteoroid Engineering Model 3.0. Most projectiles that impact Bennu come from nearly isotropic or Jupiter-family comets and have evolved toward the Sun by Poynting-Robertson drag. We find that 7,000-J impacts on Bennu occur with a biweekly cadence near perihelion, with a preference to strike in the late afternoon (~6 pm local time). This timing matches observations. Crater scaling laws also indicate that these impact energies can reproduce the sizes and masses of the largest observed particles, provided the surface has the cohesive properties of weak, porous materials. Bennu&apos;s ejection events could be caused by the same kinds of meteoroid impacts that created the Moon&apos;s asymmetric debris cloud observed by the Lunar Atmosphere and Dust Environment Explorer (LADEE). Our findings also suggest that fewer ejection events should take place as Bennu moves further away from the Sun, a result that can be tested with future observations. (C) 2020. The Authors.

Název v anglickém jazyce

Meteoroid Impacts as a Source of Bennu's Particle Ejection Events

Popis výsledku anglicky

Asteroid (101955) Bennu, a near-Earth object with a primitive carbonaceous chondrite-like composition, was observed by the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft to undergo multiple particle ejection events near perihelion between December 2018 and February 2019. The three largest events observed during this period, which all occurred 3.5 to 6 hr after local noon, placed numerous particles &lt;10 cm on temporary orbits around Bennu. Here we examine whether these events could have been produced by sporadic meteoroid impacts using the National Aeronautics and Space Administration&apos;s (NASA) Meteoroid Engineering Model 3.0. Most projectiles that impact Bennu come from nearly isotropic or Jupiter-family comets and have evolved toward the Sun by Poynting-Robertson drag. We find that 7,000-J impacts on Bennu occur with a biweekly cadence near perihelion, with a preference to strike in the late afternoon (~6 pm local time). This timing matches observations. Crater scaling laws also indicate that these impact energies can reproduce the sizes and masses of the largest observed particles, provided the surface has the cohesive properties of weak, porous materials. Bennu&apos;s ejection events could be caused by the same kinds of meteoroid impacts that created the Moon&apos;s asymmetric debris cloud observed by the Lunar Atmosphere and Dust Environment Explorer (LADEE). Our findings also suggest that fewer ejection events should take place as Bennu moves further away from the Sun, a result that can be tested with future observations. (C) 2020. The Authors.

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

2020

Kód důvěrnosti údajů

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

Název periodika

Journal of Geophysical Research. Planets

ISSN

2169-9097

e-ISSN

—

Svazek periodika

125

Číslo periodika v rámci svazku

8

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

16

Strana od-do

e2019JE006282

Kód UT WoS článku

000566216900012

EID výsledku v databázi Scopus

2-s2.0-85089851965