Precipitation of suprathermal solar wind electrons downward along magnetic field lines provides an important energy source to the martian upper atmosphere, and is the dominant external energy source…

This federal contract award is a $335,128.97 grant to the Regents of the University of California, doing business as the University of California, Berkeley (UC Berkeley), from a civilian government agency. The grant is for research on "Electron Impact Effects in the Martian Nightside Ionosphere", which aims to develop an empirical model of electron impact processes in the Mars nightside upper atmosphere using data from the MAVEN mission. This research will be implemented in global thermosphere-ionosphere models to investigate the effects of electron precipitation on the Mars nightside. The award is not associated with a set-aside program. UC Berkeley has extensive experience conducting advanced scientific research for federal agencies like NASA, the Department of Defense, and the National Institutes of Health, often as a prime or subcontractor. The parent organization for UC Berkeley is the State of California Controllers Office, which has also secured numerous federal contract awards and grants across domains such as public health, scientific research, and technological innovation.

Precipitation of suprathermal solar wind electrons downward along magnetic field lines provides an important energy source to the martian upper atmosphere, and is the dominant external energy source on the nightside. This precipitation is the primary source of ION production and drives much of the chemistry and dynamics of the nightside ionosphere, which in turn affects the neutral atmosphere. Global thermosphere-ionosphere models (gtims), which are an invaluable investigative tool for understanding the mars upper atmosphere and ionosphere, have long ignored the effects of this precipitation because sufficient data did not exist to adequately characterize their magnitudes, patterns or variability. As a result, gtim predictions of nightside ionospheric density structure compare very poorly with in situ data sets from the maven mission. We propose to remedy this situation by creating an empirical model of frequencies of a wide range of electron impact processes (including ionization, dissociation and excitation) on the mars nightside, using almost 3 years of electron flux data from the maven mission, along with published cross-sections for these processes. This empirical model will capture variability in these processes with respect to altitude, atmospheric pressure, solar wind conditions and the strength and elevation angle of the local magnetic field. We will then implement this empirical model within two of the world??s leading mars gtims, allowing US to investigate, for the first time, the global effects of electron precipitation on the mars nightside ionosphere and thermosphere, over diurnal, seasonal and solar cycles. Finally, for validation, we will compare these updated predictions of nightside ionospheric structure with in situ measured ION densities. The proposed work will thus provide the first comprehensive view at the expected effects of this dominant energy input on the nightside upper atmosphere of mars