• Nie Znaleziono Wyników

• First time determination of Chandler Wobble (CW) of a solar system body other than the Earth

N/A
N/A
Protected

Academic year: 2021

Share "• First time determination of Chandler Wobble (CW) of a solar system body other than the Earth "

Copied!
2
0
0

Pełen tekst

(1)

• First time determination of Chandler Wobble (CW) of a solar system body other than the Earth

→CW is a rotation normal mode (describes a rotational motion of the mantle)

→continuously excited by the atmosphere (most likely mechanism)

→decay time between 7-63 years (Earth 28-299 years)

→amplitude on surface ~10 cm, period=206.9d, and Q

CW

=40-350 (Earth: 433.d, Q

CW

=74-789)

• Updated precession rate

→MOI=0.36340±0.00006 (2016: MOI=0.3638±0.0001) (RISE paper MOI=0.3637±0.0001)

• Updated value of semi-diurnal solar tidal Love number

slightly larger than 2016 value mainly because of updated atmospheric correction

→k

2

=0.174±0.008 (2016: k

2

=0.169±0.006)

Consequences of updated geodesy data on interior structure models

This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process which may lead to differences between this version and the Version of Record. Please cite this article as doi:

10.1029/2020GL090568

©2020 American Geophysical Union. All rights reserved.

Konopliv Alex (Orcid ID: 0000-0001-8669-1866) Park Ryan S. (Orcid ID: 0000-0001-9896-4585) Rivoldini Attilio (Orcid ID: 0000-0002-8626-9283) Baland Rose-Marie (Orcid ID: 0000-0002-5907-0033) Le Maistre Sébastien (Orcid ID: 0000-0002-9524-9479) Van Hoolst Tim (Orcid ID: 0000-0002-9820-8584)

Detection of the Chandler Wobble of Mars from Orbiting Spacecraft

Alex. S. Konopliv1, Ryan S. Park1, Attilio Rivoldini2, Rose-Marie Baland2, Sebastien Le Maistre2, Tim Van Hoolst2, Marie Yseboodt2, Veronique Dehant2

1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA

2Royal Observatory of Belgium, Avenue Circulaire 3, B-1180 Brussels, Belgium

Corresponding author: Alex Konopliv (Alex.Konopliv@jpl.nasa.gov)

Key Points:

For the first time, the Chandler wobble has been detected for a solar system body other than the Earth

The Chandler wobble is visible in the tracking data from two Mars orbiting spacecraft The Chandler wobble significantly improves our understanding of the long period

behavior of the mantle rheology

doi: 10.1029/2020GL090568

(2)

Consequences of updated geodesy data on interior structure models

EH LF MM TA YO

���� ���� ���� ���� ����

����

����

����

����

����

����-������� ����� ���� ������ �

����������[��]

EH LF MM TA YO

��� ��� ��� ��� ���

����

����

����

����

����

�������� ������ ������ [�]

����������[��]

Chandler Wobble and rheology Effect of k2 on core radius Effect of MOI and k

2

on crust

�� �� �� �� ��

����

����

����

����

����

����

���������

������

���-������-�����

�� �� �� �� ��

����

����

����

����

����

����

���������

������

���-������-�����

�� �� �� �� ��

����

����

����

����

����

���������

������

��-������-�����

�� �� �� �� ��

����

����

����

����

����

���������

������

��-������-�����

Cold Hot

El as ti c N o n -E las ti c

2016

• core radius 1750-1880km

slightly larger core radius than with 2016 value

• MOI Taylor composition only possible for hot mantles and thick crusts

• MOI and k

2

favor thick crust for (TAY, LF, EH45) compositions except

Yoshizaki (YO)

Crust thickness-density M.W. 2020

• almost no constraint on core radius (CW period depends on mantle m.o.i.

and k

2

but effects are opposing)

• strong dependence on mantle non- elasticity

• constraints long period (~200d)

dependency of mantle rheology

Cytaty

Powiązane dokumenty

Processes of forming sheet metal products. Procesy

– In the situation presented in c) – the conditions of the task realization by the engine are formulated in the most tolerant way, irrespective of the usability limitations (also

[r]

Higher level of folic acid in the umbilical cord blood was found in female neonates, born to older mothers with shorter pregnancy duration, women having higher education, unemployed,

The procedure presented in this paper assumes the use of statistical data related to the failures of uniform population of nonrenewable technical objects, recorded in the form

Chapter 5 handles precession and nutation of the rigid Earth (i.e., a celestial body that cannot, by definition, deform) and the subsequent chapter takes deformation into

Solar collectors operate together with central heating systems based on conventional energy sources, biomass boilers and heat pumps.. Installations using biomass are often use

In this study we used MCES to: (1) rank the importance of the features that we extracted for users in YouTube, (2) standardize and set criteria, and (3) combine the criteria based