maven: mission to mars (mars atmosphere and volatile evolution) presented by dr. harold a. geller 1

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MAVEN: Mission to Mars(Mars Atmosphere and Volatile EvolutioN)

Presented byDr. Harold A. Geller

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Launched:18 November 2013

Mars Orbit Insertion:22 September 2014

The MAVEN Spacecraft

Same length as a school bus – wingtip-to-wingtip length of 37ft.

Same weight fully loaded as a full-sized SUV ~6000 lbs

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The MAVEN Spacecraft

• 3-axis attitude control (wheel based)• Mono-propellant propulsion system• Single-fault tolerant during all critical events• Launch (Wet) Mass: 2550 kg max• Spacecraft Dry Mass: 903 kg max • Power: 1135 W at Mars Aphelion

MAG (2)

“Gull-Wing” Solar Arrays

LPW (2)

SWEA

Articulated Payload Platform (IUVS/STATIC/NGIMS)

Fixed HGA

SWIA

SEP

SEP

Electra (behind)

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The MAVEN Spacecraft

MAG (2)

“Gull-Wing” Solar Arrays

LPW (2)

SWEA

Articulated Payload Platform (IUVS/STATIC/NGIMS)

Fixed HGA

SWIA

SEP

SEP

Electra (behind)

Sun, Solar Wind, Solar Storms

SWIAEUV

SWEA

SEP

Ion-Related Properties and Processes

LPWMAGSTATIC

Neutrals and Ions Plus Evolution

IUVS NGIMS5

Two Major Mysteries to Address

1. Where did the water go?6

Primordial Mars Concept

Up

Down

2. Where Did the Atmosphere Go?

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• How much atmosphere is escaping today?

• What processes strip atmospheric particles?

• How much atmosphere has escaped over history?

• How important have the ‘ups’ been?

• What can Mars teach us about other planets?

MAVEN Seeks Answers

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The Solar Wind Removes Atmosphere

Mars lacks a global magnetic field like the Earth

Mars Computer SimulationMars Cartoon 9

Upper Atmosphere and Interplanetary Space - A Coupled System

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History of Solar Activity

Photochemical and Jeans escape

Ion outflow

Sputtering

Solar wind pickup

Ion bulk escape

Physical & Empirical Models

NGIMS IUVS

Isotope Ratios

Total Loss Through Time

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This image shows the size of MAVEN's initial orbit when it first arrived at Mars, and then its current orbit after carrying out four maneuvers. The current orbit is very close to MAVEN's final science mapping orbit.Credit: University of Colorado/NASA

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Artist’s rendition of the MAVEN spacecraft in orbit around Mars, with all of the booms deployed and instruments turned on.  For scale, the spacecraft is 37 feet in length from tip to tip of the solar panels and extensions.Credit: University of Colorado/NASA

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Atomic hydrogen scattering ultraviolet sunlight in the upper atmosphere of Mars, imaged by MAVEN’s Imaging Ultraviolet Spectrograph. Hydrogen is produced by the breakdown of water, which was once abundant on Mars' surface. Hydrogen is light and weakly bound by gravity, so it extends far from the planet (indicated with a red circle) and can readily escape.Credit: University of Colorado; NASA

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Atomic carbon scattering ultraviolet sunlight in the upper atmosphere of Mars, imaged by MAVEN’s Imaging Ultraviolet Spectrograph. Carbon is produced by the breakdown of carbon dioxide, a potent greenhouse gas thought to be abundant in Mars’ past.  Mars is indicated with a red circle; sunlight is illuminating the planet from the right.Credit: University of Colorado; NASA

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Atomic oxygen scattering ultraviolet sunlight in the upper atmosphere of Mars, imaged by MAVEN’s Imaging Ultraviolet Spectrograph. Atomic oxygen is produced by the breakdown of carbon dioxide and water. Most oxygen is trapped near the planet, (indicated with a red circle) but some extends high above the planet and shows that that Mars is losing the gas to space.Credit: University of Colorado; NASA

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Three views of an escaping atmosphere, obtained by MAVEN’s Imaging Ultraviolet Spectrograph. By observing all of the products of water and carbon dioxide breakdown, MAVEN's remote sensing team can characterize the processes that drive atmospheric loss on Mars. These processes may have transformed the planet from an early Earthlike climate to the cold and dry climate of today.Credit: University of Colorado; NASA

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The geographical distribution of ozone in the southern hemisphere of Mars, imaged by MAVEN’s Imaging Ultraviolet Spectrograph. On Mars, ozone is primarily destroyed by the combined action of water vapor and sunlight. The cold, dark conditions near the pole allow ozone to accumulate there.Credit: University of Colorado; NASA; LATMOS/CNES

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This image shows the sequence of events leading up to the first SEP event observed my MAVEN at Mars. The top panel shows the distance between MAVEN and Mars as a function of time.  The bottom Panel show Energetic Ion Flux as a function of particle energy (vertical axis) and time (horizontal axis).Credit: Davin Larson

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Coronagraph image taken by SOHO spacecraft from near Earth. From this this view angle the CME is heading to the left towards Mars.Credit: ESA/NASA SOHO

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Coronagraph image taken by STEREO spacecraft with is currently situated on the far side of the Sun. From this this view angle the CME is heading to the right towards Mars.Credit: NASA STEREO Mission

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 This video shows the evolution of the Sept. 26, 2014, coronal mass ejection shock front as it propagates toward Mars as generated by the WSA-Cone-ENLIL model simulations performed at the NASA Community Coordinated Modeling Center. The color map represents the density of the solar wind plasma in the inner heliosphere from near the sun out to twice the distance of Earth's orbit.Credit: NASA's Goddard Space Flight Center

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Next Step: Comet Encounter

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Comet C/2013 A1 Siding Spring (image by Hubble Space Telescope)

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Artist Concepts

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• MAVEN Educator Ambassador (MEA) project lessons and interactiveshttp://lasp.colorado.edu/home/maven/education-outreach/for-educators/mea/

• Red Planet: Read, Write, Explore! lessons http://lasp.colorado.edu/home/maven/education-outreach/for-educators/red-planet

• Invisible Mars: Science on a Sphere script & playlist http://lasp.colorado.edu/home/maven/education-outreach/afterschoolsummer-programs/invisible-mars

• You can also share our MAVEN2Mars Twitter, Facebook, and YouTube links, if your audience would like to stay up-to-date on mission news:

• https://twitter.com/MAVEN2Mars• https://www.facebook.com/MAVEN2Mars• https://www.youtube.com/user/MAVEN2Mars

http://www.nasa.gov/maven http://lasp.colorado.edu/home/maven

Education & Outreach Resources

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