Planets and Moons  ID: 4346

MAVEN Stellar Occultation Atmospheric Coverage

NASA’s Mars Atmosphere and Volatile Evolution mission, or MAVEN, is the first spacecraft specifically designed to study the Mars upper atmosphere. MAVEN’s goal is to understand how Mars lost its thick, early atmosphere to space, and how this in turn caused it to lose its once hospitable climate.

MAVEN’s orbit gives it the most comprehensive view of the Martian atmosphere to date. Circling the red planet every 4.5 hours on an elliptical path, MAVEN passes close to the north and south poles at an inclination of 75 degrees. This allows MAVEN to gather a north-south swath of data with each pass. At the same time, Mars itself rotates eastward beneath MAVEN, giving the orbiter longitudinal coverage. The combination of MAVEN’s orbit and Mars’ daily rotation provides a complete picture of the Martian atmosphere every day.

While previous Mars orbiters have peered down at the planet's surface, MAVEN is spending part of its time gazing at the stars, observing the Martian atmosphere through a series of stellar occultations. As Mars rolls beneath MAVEN, due to the spacecraft's own orbital motion, background stars rise and set behind the planet. Their light dims as it passes through the tenuous atmosphere, with specific gases absorbing specific wavelengths. MAVEN uses its Imaging Ultraviolet Spectrograph to break apart this light and see which wavelengths are absorbed, allowing it to determine atmospheric composition at varying altitudes.
 

Related


For More Information

NASA.gov


Visualization Credits

Kel Elkins (USRA): Lead Visualizer
Dan Gallagher (USRA): Lead Producer
Greg Shirah (NASA/GSFC): Visualizer
Ernie Wright (USRA): Visualizer
Bruce Jakosky (LASP): Scientist
Please give credit for this item to:
NASA's Scientific Visualization Studio

Short URL to share this page:
http://svs.gsfc.nasa.gov/4346

Mission:
MAVEN: Mars Atmosphere and Volatile EvolutioN

Keywords:
SVS >> HDTV
SVS >> Mars
GCMD >> Earth Science >> Atmosphere
SVS >> Orbit
SVS >> MAVEN
NASA Science >> Planets and Moons
SVS >> Swath
SVS >> Occultation
SVS >> Stellar Occultation
SVS >> Orbit Coverage

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 8.0.0.0.0