Using a discrete element method to investigate seismic response and spin change of 99942 Apophis during its 2029 tidal encounter with Earth

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F19%3A00521592" target="_blank" >RIV/67985815:_____/19:00521592 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1016/j.icarus.2019.03.015" target="_blank" >https://doi.org/10.1016/j.icarus.2019.03.015</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.icarus.2019.03.015" target="_blank" >10.1016/j.icarus.2019.03.015</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Using a discrete element method to investigate seismic response and spin change of 99942 Apophis during its 2029 tidal encounter with Earth

Popis výsledku v původním jazyce

We represent Earth as a single rigid sphere and the target body as a cohesionless, self-gravitating granular aggregate of identical spheres in a hexagonal-close-packed configuration subject only to gravitational and soft-sphere (elastic) contact forces. We use a radar-derived shape model for the asteroid, along with current best estimates for the orbital solution of Apophis to simulate the encounter trajectory, and perform a large parameter sweep over different potential encounter orientations and bulk densities for the body. We find that the median change in the rotational period for Apophis, sampled for a range of different initial body and spin orientations, is -1.9 h (mean -0.1 +/- 6.0 (1-sigma) hours) during the encounter. Additionally, we measure that the mean of the largest change in axis length among the 3 primary body axes, also sampled over trials with different initial body and spin orientations, is 0.132 +/- 0.066 mm during the encounter, assuming a bulk Young's Modulus of 10(6) Pa. Such strains on the timescale of peak stress during the encounter may be large enough to be detected by an in-situ seismometer.

Název v anglickém jazyce

Using a discrete element method to investigate seismic response and spin change of 99942 Apophis during its 2029 tidal encounter with Earth

Popis výsledku anglicky

We represent Earth as a single rigid sphere and the target body as a cohesionless, self-gravitating granular aggregate of identical spheres in a hexagonal-close-packed configuration subject only to gravitational and soft-sphere (elastic) contact forces. We use a radar-derived shape model for the asteroid, along with current best estimates for the orbital solution of Apophis to simulate the encounter trajectory, and perform a large parameter sweep over different potential encounter orientations and bulk densities for the body. We find that the median change in the rotational period for Apophis, sampled for a range of different initial body and spin orientations, is -1.9 h (mean -0.1 +/- 6.0 (1-sigma) hours) during the encounter. Additionally, we measure that the mean of the largest change in axis length among the 3 primary body axes, also sampled over trials with different initial body and spin orientations, is 0.132 +/- 0.066 mm during the encounter, assuming a bulk Young's Modulus of 10(6) Pa. Such strains on the timescale of peak stress during the encounter may be large enough to be detected by an in-situ seismometer.

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/GA17-00774S" target="_blank" >GA17-00774S: Fyzikální vlastnosti a evoluční procesy subkilometrových asteroidů</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

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

Název periodika

Icarus

ISSN

1090-2643

e-ISSN

—

Svazek periodika

328

Číslo periodika v rámci svazku

August

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

11

Strana od-do

93-103

Kód UT WoS článku

000469159500009

EID výsledku v databázi Scopus

2-s2.0-85063377582