Bruce Jakosky, Principal Investigator University of Colorado Bob Lin, Deputy PI Univ. of California, Berkeley American Astronautical Society meeting 19 November 2008 Mars Atmosphere and Volatile EvolutioN (MAVEN) Mars Scout Mission

What Science Questions Will MAVEN Address? MAVEN will determine the role that loss of volatiles to space has played through time, providing definitive answers about Mars climate history: What is the current state of the upper atmosphere and what processes control it? What is the escape rate at the present epoch and how does it relate to the controlling processes? What has the total loss to space been through time? MAVEN Presentation to MEPAG, 18 September 2008 • CU/LASP, GSFC, UCB/SSL, LM, JPL

MAVEN will determine the role that loss of volatiles to space has played through time, providing definitive answers about Mars climate history:

What is the current state of the upper atmosphere and what processes control it?

What is the escape rate at the present epoch and how does it relate to the controlling processes?

What has the total loss to space been through time?

Why These Science Questions? The history of liquid water and of the atmosphere determine Mars’ potential for life throughout time. There is abundant evidence for climate change and atmospheric evolution. Loss of atmospheric CO 2 , N 2 , and H 2 O to space has been an important mechanism for atmospheric evolution, and may have been the dominant mechanism. Only by understanding the role of escape to space will we be able to fully understand the history of the atmosphere, climate, and water, and thereby understand Martian habitability.

The history of liquid water and of the atmosphere determine Mars’ potential for life throughout time.

There is abundant evidence for climate change and atmospheric evolution.

Loss of atmospheric CO 2 , N 2 , and H 2 O to space has been an important mechanism for atmospheric evolution, and may have been the dominant mechanism.

MAVEN will continue the successful “follow the water” theme. MGS, MPF, ODY, MER, MRO, MEx, now PHX, upcoming MSL, are focused largely on the history of the surface. MAVEN’s comprehensive approach will provide the history of the atmosphere as the other necessary half of the story.

Mars Magnetic Field (from MGS Magnetometer/ Electron Reflectometer) )

MAVEN Presentation to MEPAG, 18 September 2008 • CU/LASP, GSFC, UCB/SSL, LM, JPL

Some of the evidence for the Importance of Loss to Space Isotopic fractionation that cannot be explained except by loss to space. Direct detection of energetic ions moving away from the planet by Mars Express . Energetic pickup ions detected by Phobos . MGS observations of dramatic atmospheric depletion in response to a solar energetic particle (SEP) event.

Isotopic fractionation that cannot be explained except by loss to space.

Direct detection of energetic ions moving away from the planet by Mars Express .

Energetic pickup ions detected by Phobos .

MGS observations of dramatic atmospheric depletion in response to a solar energetic particle (SEP) event.

MAVEN Will Measure the Drivers, Reservoirs, and Escape Rates MAVEN will determine the present state of the upper atmosphere and today’s rates of loss to space. Essential measurements allow determination of the net integrated loss to space through time.

MAVEN will determine the present state of the upper atmosphere and today’s rates of loss to space.

Essential measurements allow determination of the net integrated loss to space through time.

Constraining the Total Atmospheric Loss Through Time History of Solar Activity Physical & Empirical Models Isotope Ratios Photochemical and Jeans escape Ion outflow Sputtering Solar wind pickup Ion bulk escape NGIMS IUVS

Sun-pointed spacecraft with body-mounted instruments. Three boom- and solar-panel-mounted instruments. Articulated payload platform (APP) to align FOVs of NGIMS, STATIC, and IUVS with velocity vector and planet. MAVEN Spacecraft

Sun-pointed spacecraft with body-mounted instruments.

Three boom- and solar-panel-mounted instruments.

Articulated payload platform (APP) to align FOVs of NGIMS, STATIC, and IUVS with velocity vector and planet.

Launch: November 18, 2013 One Year of Science Operations MAVEN Mission Architecture Ten Month Ballistic Cruise to Mars Orbit Insertion: 16 Sept 2014

“ Deep Dips” Down to the Homopause Nominal periapsis near 150 km. Five “deep-dip” campaigns with periapsis near 125 km.

Nominal periapsis near 150 km.

Five “deep-dip” campaigns with periapsis near 125 km.

The MAVEN Institutional Partnerships Project management — GSFC (Goddard Space Flight Center) Spacecraft contractor — LM (Lockheed Martin) Instrument providers — LASP (Laboratory for Atmospheric & Space Physics ), U. of Colorado SSL (Space Sciences Laboratory), U. of California, Berkeley GSFC Science team — LASP, SSL, GSFC, JPL, CESR (Centre d’Etude Spatiale des Rayonnements) Toulouse Navigation — JPL Mission operations — LM Science operations and science data center — LASP Education and public outreach — LASP

Project management — GSFC (Goddard Space Flight Center)

Spacecraft contractor — LM (Lockheed Martin)

Instrument providers —

LASP (Laboratory for Atmospheric & Space Physics ), U. of Colorado

SSL (Space Sciences Laboratory), U. of California, Berkeley

GSFC

Science team — LASP, SSL, GSFC, JPL, CESR (Centre d’Etude Spatiale des Rayonnements) Toulouse

Navigation — JPL

Mission operations — LM

Science operations and science data center — LASP

Education and public outreach — LASP