Spin state evolution of (99942) Apophis during its 2029 Earth encounter

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F23%3A00566204" target="_blank" >RIV/67985815:_____/23:00566204 - isvavai.cz</a>

Result on the web

<a href="https://hdl.handle.net/11104/0342006" target="_blank" >https://hdl.handle.net/11104/0342006</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.icarus.2022.115324" target="_blank" >10.1016/j.icarus.2022.115324</a>

Result language

angličtina

Original language name

Spin state evolution of (99942) Apophis during its 2029 Earth encounter

Original language description

We explore the effects of the 2029 Earth encounter on asteroid (99942) Apophis' non-principal axis spin state, leveraging refined orbit, spin state, and inertia information provided by more recent optical and radar observations. Propagating the asteroids' coupled orbit and rigid body attitude dynamics through the flyby, we present the range of possible post-flyby spin states. These spin state distributions will be valuable for planning Apophis observation campaigns and spacecraft missions, most notably OSIRIS-APEX. The simulations indicate that gravitationally induced changes to the asteroid's tumbling periods and rotational angular momentum direction (pole) will likely be significant and measurable. For the current spin state and inertia estimates and their uncertainties, Apophis is likely to remain in a short axis mode (SAM) tumbling state but its effective spin rate could halve or double. Its pole is likely to shift by 10 degrees or more and increase in longitude while moving closer to the ecliptic plane. These spin state changes are very sensitive to the asteroid's close approach attitude and mass distribution. With ground-based tracking of the asteroid's spin state through the encounter, this sensitivity will help refine mass distribution knowledge. We also discuss the implications of this abrupt spin state alteration for Apophis' Yarkovsky acceleration and geophysical properties, identifying possible pathways for surface and internal changes, most notably if Apophis is a contact binary. Comparison of the pre and post-flyby inertia estimates obtained from the ground-based observations will help assess the extent of possible geophysical changes.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

<a href="/en/project/GA20-04431S" target="_blank" >GA20-04431S: Physical and dynamical properties of space mission target asteroids, and their evolutionary paths</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

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

Name of the periodical

Icarus

ISSN

0019-1035

e-ISSN

1090-2643

Volume of the periodical

390

Issue of the periodical within the volume

January

Country of publishing house

US - UNITED STATES

Number of pages

10

Pages from-to

115324

UT code for WoS article

000882468000003

EID of the result in the Scopus database

2-s2.0-85141334430