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  • Electrodynamics of the Martian Dynamo RegionThe M4 Approach

    Jeremy A. Riousset,1,2 Carol S. Paty,1 Robert J. Lillis,3 Matthew O. Fillingim,3

    Scott L. England,3 Paul G. Withers,4 and John P. M. Hale11School of Earth and Atmospheric Sciences, Georgia Tech, Atlanta, GA, 30306, USA2Institut fur Theoretische Physik, TU-BS, Braunschweig, D-38106, Germany (j.riousset@tu-bs.de)3Space Sciences Lab, UC Berkeley, Berkeley, CA, 94720, USA4Astronomy Department, Boston U, Boston, MA, 02215, USA

    January 21, 2014

    TU-BS, ITP-NPS, Braunschweig, DE

  • Electrodynamics of the Martian Dynamo RegionThe M4 Approach

    Jeremy A. Riousset,1,2 Carol S. Paty,1 Robert J. Lillis,3 Matthew O. Fillingim,3

    Scott L. England,3 Paul G. Withers,4 and John P. M. Hale11School of Earth and Atmospheric Sciences, Georgia Tech, Atlanta, GA, 30306, USA2Institut fur Theoretische Physik, TU-BS, Braunschweig, D-38106, Germany (j.riousset@tu-bs.de)3Space Sciences Lab, UC Berkeley, Berkeley, CA, 94720, USA4Astronomy Department, Boston U, Boston, MA, 02215, USA

    January 21, 2014

    TU-BS, ITP-NPS, Braunschweig, DE

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    Electrodynamics of Mars dynamo region

    Keypoints:

    Mars is neither magnetized like Earth,Jupiter, Saturn, or Uranus, nor demagne-tized like Venus: hence it is curious.

    Our work is a collaboration between intru-mentalists (at SSL), and modelers (BU, GT,SSL).

    30

  • Introduction Motivations The M4 Approach Results Conclusions References

    Outline

    Introduction

    Modeling of Mars Ionosphere: Why?

    Modeling of Mars Ionosphere: How?

    Modeling of Mars Ionosphere: And?

    Conclusions

    Riousset et al. | Electrodynamics of Mars dynamo region | 3/32

  • Introduction Motivations The M4 Approach Results Conclusions References

    Outline

    Introduction

    Modeling of Mars Ionosphere: Why?

    Modeling of Mars Ionosphere: How?

    Modeling of Mars Ionosphere: And?

    Conclusions

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    Electrodynamics of Mars dynamo region

    Introduction

    Outline

    Keypoints:

    Mars is fascinating. He [Dave Brain] cantbelieve that someone is willing to pay himto think about Mars all day. About DaveBrain as a Lecturer at Berkeley.

    Here my goal is to explain to you why westudy Mars ionosphere, how our group doesit, and what our recent results are.

    100

    http://cse.ssl.berkeley.edu/astro48bcc/lecturers.htmlhttp://cse.ssl.berkeley.edu/astro48bcc/lecturers.html

  • Introduction Motivations The M4 Approach Results Conclusions References

    Objectives of the Study

    Figure : Model ~B-field configuration near a magnetic cusp.

    The M4 approach [Riousset et al., 2013a]:

    Mars (CO2, & O)Multifluid (O+2 , CO

    +2 , O

    +, & e)MagnetoHydroDynamic (MHD)Model

    Two case studies [Riousset et al., 2013b]:

    Cusp: case of the isolated buried mag-netic dipoleArcades: Terra Sirenum Analogy

    Riousset et al. | Electrodynamics of Mars dynamo region | 4/32

  • Introduction Motivations The M4 Approach Results Conclusions References

    Objectives of the Study

    Figure : Model ~B-field configuration near a magnetic cusp.

    The M4 approach [Riousset et al., 2013a]:

    Mars (CO2, & O)Multifluid (O+2 , CO

    +2 , O

    +, & e)MagnetoHydroDynamic (MHD)Model

    Two case studies [Riousset et al., 2013b]:

    Cusp: case of the isolated buried mag-netic dipoleArcades: Terra Sirenum Analogy2

    01

    4-0

    1-2

    1

    Electrodynamics of Mars dynamo region

    Introduction

    Objectives of the Study

    Keypoints:

    We are using a Multifluid, i.e., not parti-cle approach to study the macroscopic dy-namics of the atmospheric plasma, due toelectromagnetic effects, and hydrodynamic(classic fluid mechanic effects) via MHDapproach.

    Our work is based on observations of theplanets atmosphere and ionosphere (Viking)and magnetic fields (MGS/MagnetoMeter)to propose and explain of observable effects:Mars is losing its atmosphere.

    145

  • Introduction Motivations The M4 Approach Results Conclusions References

    Follow the Water!

    Mars Facts:

    g3.7 m/s2

    T210 K (130308 K)P0.006P=600 PaAtmosphere: &95% CO2, O

    Neutral winds

    Dense atmosphere

    Greenhouse effect

    Temperature

    Liquid water

    List of missions to Mars (wiki).

    http://en.wikipedia.org/wiki/List_of_missions_to_Mars

  • Introduction Motivations The M4 Approach Results Conclusions References

    Follow the Water!

    Mars Facts:

    g3.7 m/s2

    T210 K (130308 K)P0.006P=600 PaAtmosphere: &95% CO2, O

    Neutral winds

    Dense atmosphere

    Greenhouse effect

    Temperature

    Liquid water

    List of missions to Mars (wiki).

    20

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    Electrodynamics of Mars dynamo region

    Modeling of Mars Ionosphere: Why?

    Atmosphere? Atmosphere? Est-ce que jai une gueuledatmosphere? (Hotel du Nord, Marcel Carne, 1938)

    Follow the Water!

    Keypoints:

    Mars is one of the most studies planet in thesolar system. The Martian canals were ini-tially believed to be artefacts and thereforeevidences of the existence of extraterrestrialintelligent life.

    The recent space exploration programadopted the so-called Follow the waterapproach. It started by exploring the cur-rent reservoirs of H2O and the next missionMAVEN will focus on the Martian atmo-sphere/ionosphere down to 120 km.

    The presence of a dense atmosphere (muchdenser than it currently is) is absolutely nec-essary to maintain water in liquid form atthe surface, a condition which is closely as-sociated with the possibility of life.

    230

    http://en.wikipedia.org/wiki/List_of_missions_to_Mars

  • Introduction Motivations The M4 Approach Results Conclusions References

    The Thin Red Line

    Figure : Earths atmosphere today. Image cour-tesy: http://thebarometer.podbean.com/.

    Figure : Mars atmosphere today. Image courtesy:NASA.

    http://thebarometer.podbean.com/

  • Introduction Motivations The M4 Approach Results Conclusions References

    The Thin Red Line

    Figure : Earths atmosphere today. Image cour-tesy: http://thebarometer.podbean.com/.

    Figure : Mars atmosphere today. Image courtesy:NASA.

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    Electrodynamics of Mars dynamo region

    Modeling of Mars Ionosphere: Why?

    Atmosphere? Atmosphere? Est-ce que jai une gueuledatmosphere? (Hotel du Nord, Marcel Carne, 1938)

    The Thin Red Line

    Keypoints:

    It all happens in this very thin line observedin these zenith pictures. Blue on Earth dueto Rayleigh scaterring, and red one Mars.

    Mars atmosphere is much thinner thanEarths (the pictures are not to scale), be-cause it has lost most of it (96%).

    315

    http://thebarometer.podbean.com/

  • Introduction Motivations The M4 Approach Results Conclusions References

    The Great Escape

    Mars Facts:

    No dipolar, Earth-likemagnetic-field

    Remanent crustal fields

    Ionosphere: e & 71% O+2 , 25%CO+2 , 4% O

    +

    Figure : Mars Atmospheric VolatileEvolutioN (MAVEN). Image courtesy:NASA.

    Figure : Image Courtesy: [Jedrich, 2012].

    Riousset et al. | Electrodynamics of Mars dynamo region | 8/32

  • Introduction Motivations The M4 Approach Results Conclusions References

    The Great Escape

    Mars Facts:

    No dipolar, Earth-likemagnetic-field

    Remanent crustal fields

    Ionosphere: e & 71% O+2 , 25%CO+2 , 4% O

    +

    Figure : Mars Atmospheric VolatileEvolutioN (MAVEN). Image courtesy:NASA.

    Figure : Image Courtesy: [Jedrich, 2012].20

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    Electrodynamics of Mars dynamo region

    Modeling of Mars Ionosphere: Why?

    Atmosphere? Atmosphere? Est-ce que jai une gueuledatmosphere? (Hotel du Nord, Marcel Carne, 1938)

    The Great Escape

    Keypoints:

    The loss of the Martian atmosphere is be-lieved to be related to the shutoff of itscore-dynamo (4 Gyr ago). It is proba-bly not the only mechanisms, but is worthinvestigating it, we think.

    Earth is protected by its magnetosphere,but Mars is not and there are many wayin which this absence of a magnetospherecould lead to a loss of the atmosphere.

    415

  • Introduction Motivations The M4 Approach Results Conclusions References

    Marss Magnetic Environment

    Figure : Image courtey: DTU Space, [Luhmann and Russell, 1997].

    Bow shock: Supersonic/superalfvenic speed VSW=Pii

    Magnetic Pile-up Boundary: Local deflection of solar wind protons VSW=0

    Ionopause: Pressure balance:SWV

    2SW

    2=P

    http://www.space.dtu.dk/English/Research/Universe_and_Solar_System/magnetic_field.aspx

  • Introduction Motivations The M4 Approach Results Conclusions References

    Marss Magnetic Environment

    Figure : Image courtey: DTU Space, [Luhmann and Russell, 1997].

    Bow shock: Supersonic/superalfvenic speed VSW=Pii

    Magnetic Pile-up Boundary: Local deflection of solar wind protons VSW=0

    Ionopause: Pressure balance:SWV

    2SW

    2=P

    20

    14

    -01

    -21

    Electrodynamics of Mars dynamo region

    Modeling of Mars Ionosphere: Why?

    Atmosphere? Atmosphere? Est-ce que jai une gueuledatmosphere? (Hotel du Nord, Marcel Carne, 1938)

    Marss Magnetic Environment

    Keypoints:

    At Mars, the bow shock still exists due tothe planets traveling at high speed throughthe solar wind.

    The absence of a magnetic dipole to shieldthe planet reveals a drapping effect. Onthe dayside, the solar wind magnetic field isparallel to the surface, and wraps aroundthe