Proton aurora are the most recently discovered
of the three types of aurora on Mars. Due to the lack of a
global dipole magnetic field on Mars, the formation processes
and characteristics of its aurora are different than aurora on
Earth. We use data from the Mars Atmosphere and Volatile
EvolutioN (MAVEN) spacecraft to characterize Martian proton
aurora. We find that the primary factors influencing proton
aurora are solar zenith angle (SZA) and season: with the
highest intensities, emission enhancements, peak altitudes,
and occurrence rates (nearing 100%!) observed at low SZAs
(i.e., on the planet's dayside) around southern summer
solstice. This time period coincides with the onset of the
Martian dust storm season and an "inflated" extended Martian
atmosphere. Proton aurora are found to occur in ~15% of
dayside observations (with notable seasonal variability),
making them the most commonly observed type of aurora on Mars.
We also consider examples of "atypical" proton aurora
observations, evaluating their unique properties and exploring
possible alternative formation mechanisms. Through this
research we have characterized the phenomenology, variability,
and primary influencing factors of Martian proton aurora as
never before. The results of this study provide a novel and
unprecedented understanding of proton aurora on Mars, which we
find to be an important component of present-day observations
of Martian hydrogen/atmospheric escape and water loss!
About the Speaker:
Andrea is a postdoctoral associate in the
Heliophysics division of NASA Goddard Space Flight Center. She
has a diverse background in Earth and Planetary Sciences,
having studied both Martian surface and atmospheric processes.
Andrea earned her bachelor's degree in Space Sciences from
Florida Institute of Technology. She then went on to complete
a master's degree in Planetary Geology at the University of
Tennessee, Knoxville, where she did her thesis on the history
of water on Mars as observed through the minerology,
morphology, and thermophysical properties of hypothesized
Martian deltas. Andrea recently completed her PhD in
Engineering Physics from Embry-Riddle Aeronautical University.
Her PhD dissertation research entailed using data from NASA's
MAVEN spacecraft to study the phenomenology, variability, and
driving processes of Martian proton aurora. In her current
postdoc position at NASA, Andrea is working with Gina
DiBraccio (the MAVEN Project Scientist and Deputy Principal
Investigator) to study the relationship between proton aurora
and the local magnetic field environment at Mars. She is
particularly interested in interactions between the solar wind
and the Martian upper atmosphere which lead to the formation
and variability of proton aurora activity. She is also excited
to apply her knowledge and passion for multi-disciplinary
Earth/Planetary Sciences to better understand the Martian
planetary system as a whole (and to apply this knowledge to
other planetary bodies as well!).